FAIRFAX TOWN COUNCIL MEETING
STAFF REPORT
MEETING DATE July 1, 2026
PREPARED FOR Mayor and Town Council
PREPARED BY Kristin Arnold, Public Works Director
SUBJECT Conduct a Public Hearing and Adopt a Resolution Adopting the California Environmental Quality Act (CEQA) Final Initial Study and Mitigated Negative Declaration (IS/MND) and Mitigation Monitoring and Reporting Program (MMRP) for the proposed Creek Road Bridge Seismic Rehabilitation Project and Approve the Project.
RECOMMENDATION
1) Conduct public hearing
2) Adopt resolution adopting the California Environmental Quality Act (CEQA) Final Initial Study and Mitigated Negative Declaration (IS/MND) and Mitigation Monitoring and Reporting Program (MMRP) for the proposed Creek Road Bridge Seismic Rehabilitation Project and approve the project.
BACKGROUND
Much of the bridge infrastructure in the Town of Fairfax is of an older vintage, dating back 80 to 90 years. The Creek Road over San Anselmo Creek was constructed in 1929 and needs a seismic retrofit.
The purpose of the project is to retrofit Creek Road Bridge in order to enhance seismic safety, to prevent catastrophic failure during a Maximum Credible Earthquake, which is defined as the largest possible earthquake that could occur in a specific region, based on geological and seismological evidence, such as the length of active faults, and, overall, to maintain the structural integrity of the bridge in the interests of public safety.
The bridge experienced a significant washout at the west abutment during the 2005 New Year's Eve flood; subsequent repairs and a 2010 scour evaluation found no significant new foundation scour concerns. The primary issue facing the bridge is seismic vulnerability: the bridge consists of simple spans that are not securely connected to the supporting structure, creating a risk that the spans could unseat and collapse during a major earthquake. Structural analyses determined the bridge is a Category 1 Bridge, meaning it could fail catastrophically during a Maximum Credible Earthquake, posing a risk to human life. Further analysis showed that simply securing the spans would not be sufficient because the bridge's supporting columns and beams would also fail under seismic forces. As a result, both the bridge superstructure and substructure require seismic retrofit improvements. Caltrans approved a retrofit strategy designed to prevent catastrophic collapse and loss of life during a major earthquake, although the bridge may still sustain significant damage or become unusable following such an event.
The most recent milestone was the receipt of NEPA clearance from Caltrans in March 2026. The project team is working on updating funding authorizations with Caltrans to program the next phase of funding, allowing the project to move into right-of-way acquisition, utility coordination, environmental permitting, and final design.
ANALYSIS/DISCUSSION
WRA, Inc., as a subconsultant to MGE, prepared the environmental review documents for the Creek Road Bridge Seismic Rehabilitation project in accordance with the California Environmental Quality Act (CEQA).
An Initial Study was prepared for the project, which addressed all environmental topics identified in Appendix G of the CEQA Guidelines, as well as the Mandatory Findings of Significance. The Draft Initial Study determined that the project could result in potentially significant impacts to the following environmental topics: Air Quality, Biological Resources, Cultural Resources, Geology and Soils, Hazards and Hazardous Materials, Hydrology and Water Quality, Noise, Transportation, and Tribal Cultural Resources. Mitigation measures were included to reduce all identified potentially significant impacts to a less-than-significant level. As all potentially significant impacts could be fully mitigated, the Town, acting as the CEQA Lead Agency, can conclude that the project would qualify for a Mitigated Negative Declaration (MND) and therefore would not require the preparation of an Environmental Impact Report (EIR) pursuant to CEQA.
On May 7, 2026, the Town released the Draft Initial Study/Mitigated Negative Declaration (IS/MND) for public review in accordance with Section 15105 of the CEQA Guidelines. The public review and comment period began on May 7, 2026, and closed on June 8, 2026. A Notice of Availability and Intent to Adopt an IS/MND was circulated to interested parties and posted on the Town’s website along with the Draft IS/MND and its technical appendices. The Draft IS/MND was also made available at the Town Hall lobby, located at 142 Bolinas Road, Fairfax, CA 94930. A Notice of Completion, along with copies of the Draft IS/MND, was submitted to the State Clearinghouse on May 7, 2026, for review and comment by relevant State agencies. The State Clearinghouse subsequently assigned State Clearinghouse Number 2026050223.
During the 30-day public review period, no comment letters on the Draft IS/MND were submitted to the Town. The Final IS/MND was prepared and includes the Draft IS/MND and a Mitigation Monitoring and Reporting Program (MMRP).
To summarize, the Final IS/MND is a CEQA document prepared by the Lead Agency (Town of Fairfax) that must be considered by decision-makers before approving the project and that must reflect the Lead Agency’s independent judgment and analysis. Staff has concluded that all potentially significant impacts can be fully mitigated to a less-than-significant level and that the project qualifies for an MND.
Therefore, preparation of an Environmental Impact Report (EIR) is not required. If the IS/MND is not adopted, then the Town would need to either revise the environmental document or prepare additional
environmental review, which could result in delays to the project schedule and potential impacts to project funding.
Adoption of the IS/MND is a key step toward achieving environmental clearance from Caltrans, which is required for the next phase of funding. Based on the whole record, there is no substantial evidence that the project will have a significant effect on the environment with mitigation incorporated. Therefore, staff recommends that the Town Council adopt the IS/MND and Mitigation Monitoring and Reporting Program (MMRP) and approve the project.
FISCAL IMPACT
CEQA costs are fully the responsibility of the Town, while the remainder of the Creek Road Bridge Seismic Rehabilitation project is 88.53% funded by the federal Highway Bridge Program (HBP), administered by Caltrans. The Town is responsible for the remaining 11.47%.
The Town has an existing contract with MGE Engineering to prepare design and environmental review services for this project and other bridge projects in Town.
ATTACHMENTS
A. Resolution adopting IS/MND and approving the Creek Road Bridge Seismic Rehabilitation Project B. IS/MND including MMRP
Town of Fairfax ATTACHMENT A
Resolution No. 2026-
RESOLUTION NO. 2026
A RESOLUTION OF THE TOWN COUNCIL OF THE TOWN OF FAIRFAX ADOPTING THE
CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA) INITIAL STUDY AND MITIGATED
NEGATIVE DECLARATION (IS/MND) AND MITIGATION MONITORING AND REPORTING
PROGRAM (MMRP) FOR THE PROPOSED CREEK ROAD BRIDGE SEISMIC REHABILTATION PROJECT AND APPROVING THE PROJECT.
WHEREAS, the Town of Fairfax proposes to implement the Creek Road Bridge Seismic Rehabilitation Project, the project will help maintain the Town’s bridge infrastructure and extend the service life of this facility, and is the Lead Agency for the project pursuant to the California Environmental Quality Act (CEQA); and
WHEREAS, an Initial Study was prepared in accordance with CEQA Guidelines Sections 15060 et seq. and 15070 et seq., which identified potentially significant impacts in the areas of Air Quality, Biological Resources, Cultural Resources, Geology and Soils, Hazards and Hazardous Materials, Hydrology and Water Quality, Noise, Transportation, and Tribal Cultural Resources, and recommended mitigation measures to reduce all such impacts to a less-than-significant level; and WHEREAS, a Draft Initial Study/Mitigated Negative Declaration (IS/MND) was circulated for public review from May 7, 2026 through June 8, 2026, in accordance with CEQA Guidelines Section 15105, and a Notice of Completion was submitted to the State Clearinghouse (State Clearinghouse No. 2026010532); and
WHEREAS, no comments were submitted during the public review period, and a Final IS/MND was prepared, including a Mitigation Monitoring and Reporting Program (MMRP), which reflects the independent judgment and analysis of the Town of Fairfax; and WHEREAS, the Town Council has reviewed and considered the Final IS/MND, the staff report, all oral and written testimony, and the entire administrative record, and held a duly noticed public hearing on July 1, 2026, at which all interested parties had the opportunity to be heard; and WHEREAS, based on the whole record before the Town Council, there is no substantial evidence that the project will have a significant effect on the environment with mitigation measures incorporated, and the Final IS/MND does not identify any new or substantially more severe impacts than those identified in the Draft IS/MND; therefore, an Environmental Impact Report is not required and recirculation is not required pursuant to CEQA Guidelines Section 15073.5; and WHEREAS, adoption of the IS/MND and MMRP is necessary to advance the project into the next phase, including right-of-way, permitting, and final design, and to maintain eligibility for federal funding through the Highway Bridge Program (HBP);
NOW, THEREFORE, BE IT RESOLVED that the Town Council of the Town of Fairfax does hereby:
1. Adopt the Final Initial Study/Mitigated Negative Declaration (IS/MND) (State Clearinghouse No. 2026050223) for the Bridge Preventive Maintenance Project.
2. Adopt the Mitigation Monitoring and Reporting Program (MMRP) for the project, and directs that all mitigation measures shall be implemented and monitored in accordance with the MMRP.
3. Find that the IS/MND reflects the independent judgment of the Town of Fairfax and that it Town of Fairfax ATTACHMENT A
Resolution No. 2026-
has been completed in compliance with CEQA and the CEQA Guidelines.
4. Approve the Creek Road Bridge Seismic Rehabilitation Project as described in the Final IS/MND.
5. Direct staff to file a Notice of Determination (NOD) with the Marin County Clerk and the State Clearinghouse in accordance with CEQA.
PASSED, APPROVED, AND ADOPTED by the Town Council of the Town of Fairfax on this 1st day of July 2026, by the following vote:
AYES:
NOES:
ABSTAIN:
ABSENT:
ATTEST
______________________________ __________________________________
STEPHANIE HELLMAN CHRISTINE FOSTER
MAYOR DEPUTY TOWN CLERK
Final Initial Study / Mitigated Negative Declaration
Creek Road Bridge Rehabilitation Project
Town of Fairfax, Marin County, California
Prepared for: Prepared by:
Town of Fairfax
142 Bolinas Road
Fairfax, California 94930
Attn: Kristin Arnold
Public Works Director
[email protected]
WRA, Inc.
2169 G East Francisco Boulevard
San Rafael, CA 94901
Attn: Justin Semion
Technical Services Director
[email protected]
June 2026 WRA #22304
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Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 i
Contents
1.0 INTRODUCTION AND PURPOSE................................................................................................ 5
2.0 PROJECT INFORMATION...........................................................................................................5
2.1 Project Title...................................................................................................................5
2.2 Lead Agency Name and Address ................................................................................5
2.3 Contact Person and Phone Number ............................................................................5
2.4 Project Location............................................................................................................5
2.5 General Plan Designation and Zoning District............................................................6
2.5.1 General Plan Designation ................................................................................6
2.5.2 Zoning District..................................................................................................6
3.0 PROJECT DESCRIPTION...........................................................................................................11
3.1 Project Background and Purpose...............................................................................11
3.2 Detailed Description of the Project ...........................................................................11
3.3 Project Construction ...................................................................................................12
3.3.1 Construction Schedule ...................................................................................12
3.3.2 Site Access and Staging ................................................................................12
3.3.3 Site Work ........................................................................................................12
3.4 Project–Related Approvals, Agreements, and Permits ............................................16
3.4.1 Army Corps of Engineers ...............................................................................16
3.4.2 California Department of Fish and Wildlife..................................................16
3.4.3 Regional Water Quality Control Board .........................................................16
4.0 ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED.........................................................17
4.1 Determination .............................................................................................................17
4.2 Initial Study Checklist.................................................................................................18
4.2.1 Aesthetics .......................................................................................................19
4.2.2 Agricultural and Forestry Resources ............................................................. 22
4.2.3 Air Quality.......................................................................................................24
4.2.4 Biological Resources ......................................................................................28
4.2.5 Cultural Resources .........................................................................................45
4.2.6 Energy.............................................................................................................49
4.2.7 Geology and Soils ..........................................................................................50
4.2.8 Greenhouse Gas Emissions ............................................................................55
4.2.9 Hazards and Hazardous Materials ............................................................... 58
4.2.10 Hydrology and Water Quality........................................................................62
4.2.11 Land Use and Planning..................................................................................67 Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 ii
4.2.12 Mineral Resources..........................................................................................70
4.2.13 Noise...............................................................................................................71
4.2.14 Population and Housing ................................................................................81
4.2.15 Public Services ............................................................................................... 82
4.2.16 Recreation ......................................................................................................85
4.2.17 Transportation................................................................................................ 86
4.2.18 Tribal Cultural Resources...............................................................................89
4.2.19 Utilities and Service Systems ........................................................................92
4.2.20 Wildfire ...........................................................................................................96
4.2.21 Mandatory Findings of Significance ............................................................. 99
5.0 RESPONSE TO COMMENTS...................................................................................................103
6.0 MITIGATION MONITORING AND REPORTING PROGRAM ...................................................104
7.0 REFERENCES.......................................................................................................................... 119 List of Tables
Table 1. Proposed Project Direct Impacts to Natural Communities of Special Concern ................40 Table 2. Proposed Project Direct Impacts to Jurisdictional Areas by Agency .................................40 Table 3. Typical Noise Levels in the Environment.............................................................................73 Table 4. Reactions of People and Damage to Buildings from Continuous or Frequent Intermittent Vibration Levels...................................................................................................................................74 Table 5. Exterior Noise Limits.............................................................................................................76 Table 6. Vibration Source Levels for Construction Equipment..........................................................79 Table 7. Mitigation Monitoring and Reporting Program.................................................................105 List of Figures
Figure 1. Project Site Regional Location ..............................................................................................7 Figure 2. Aerial Photograph of the Project Site...................................................................................8 Figure 3. Views of the Project Site .......................................................................................................9 Figure 4. Views of Surrounding Land Uses ........................................................................................10 Figure 5. Creek Road Bridge Seismic Retrofit Details .......................................................................15 Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 iii
List of Appendices
Appendix A. Natural Environment Study
Appendix B. Biological Assessment
Appendix C. Noise Study
Appendix D. Cultural Resources Reports
List of Acronyms & Abbreviations
AAQS ambient air quality standards
ABAG Association of Bay Area Governments
APE Area of Potential Effects
ASR Archaeological Survey Report
BA Biological Assessment
BAAD Bay Area Air District
BMPs Best Management Practices
BSA Biological Study Area
Bridge Creek Road Bridge
CAL FIRE California Department of Fire and Forestry
Caltrans California Department of Transportation
CAMUTCD California Manual on Uniform Traffic Control Devices CAP Clean Air Plan
CCC Central California Coast
CCR California Code of Regulations
CDFG California Department of Fish and Game
CDFW California Department of Fish and Wildlife
CDOC California Department of Conservation
CESA California Endangered Species Act
CEQA California Environmental Quality Act
CFR Code of Federal Regulations
CGS California Geological Survey
CH4 methane
CMP Congestion Management Program
CNDDB California Natural Diversity Database
CNEL Community Noise Equivalent Level
CNPS California Native Plant Society
CO2 carbon dioxide
Corps United States Army Corps of Engineers
CRHR California Register of Historic Resources
CWA Clean Water Act
dB decibel
dBA A-weighted decibel scale
DOT Department of Transportation
DTSC Department of Toxic Substances Control
EFH Essential Fish Habitat
EMS Emergency Service Vehicles
EPA Environmental Protection Agency
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 iv
ESA Endangered Species Act
Far Western Far Western Anthropological Research Group Inc.
FEMA Federal Emergency Management Agency
FHWA Federal Highway Administration
FHSZ Fire Hazard Severity Zone
FIRM Federal Insurance Rate Maps
FPD Fairfax Police Department
GHGs Greenhouse Gases
HPSR Historical Property Survey Report
HRER Historical Resources Evaluation Report
I&R Illingworth and Rodkin
IS/MND Initial Study/Mitigated Negative Declaration
JRP JRP Historical Consulting, LLC
Ldn Day/Night Average Sound Level
MCSTOPPP Marin County Stormwater Pollution Prevention Program MLD Most Likely Descendant
MMWD Marin Municipal Water District
NAHC Native American Heritage Commission
NBI National Bridge Inventory
NES Natural Environment Study
NMFS National Marine Fisheries Service
NPDES National Pollutant Discharge Elimination System
N2O nitrous oxide
NOx Oxides of nitrogen
NSR New Source Review
NRHP National Register of Historic Places
O3 Ozone
OHW Ordinary High Water
PM Particulate matter
PPV Peak Particle Velocity
PRC Public Resources Code
ROG reactive organic gases
RVFD Ross Valley Fire Department
RWQCB Regional Water Quality Control Board
SFBAAB San Francisco Bay Area Air Basin
SIP State Implementation Plan
SWPPP Storm Water Prevention Program
SWQCB State Water Quality Control Board
TNS Technical Noise Supplement
Town Town of Fairfax
TPY tons per year
USDA United States Department of Agriculture
USFWS United States Fish and Wildlife Service
VMT Vehicle Miles Traveled
WDR Waste Discharge Requirement
WRA WRA, Inc.
WUI Wildland Urban Interface
XPI Extended Phase I
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 5 1.0 INTRODUCTION AND PURPOSE
This Initial Study/Proposed Mitigated Negative Declaration (IS/MND) of environmental impacts is being prepared to conform to the requirements of the California Environmental Quality Act (CEQA) Statute and Guidelines (California Code of Regulations 15000 et. seq.). This IS/MND evaluates the potential environmental impacts which might reasonably be anticipated to result from implementation of the Creek Road Bridge Project (proposed project). The Town of Fairfax (Town) is the Lead Agency as defined under CEQA Guidelines Section 15050.
The purpose of an Initial Study is to provide the Lead Agency with information to use as the basis for deciding whether to prepare an Environmental Impact Report or a Negative Declaration for the proposed project. A Negative Declaration briefly describes the reason that a proposed project would result in a significant effect on the environment, and the basis of the decision not to prepare an EIR. This Initial Study describes the Town’s efforts to ensure that all resource impacts are reduced to less-than-significant level with mitigation incorporated, qualifying for a Proposed Mitigated Negative Declaration.
This IS/MND provides the Town and the public with an understanding of the potential environmental impacts associated with the Proposed project. The purpose of the proposed project includes the physical modifications of the Creek Road Bridge in the Town of Fairfax that is proposed to undergo seismic retrofit.
2.0 PROJECT INFORMATION
2.1 Project Title
Creek Road Bridge Project
2.2 Lead Agency Name and Address
Town of Fairfax
142 Bolinas Road
Fairfax, California 94930
2.3 Contact Person and Phone Number
Kristin Arnold
Public Works Director
(415) 453-0291
[email protected]
2.4 Project Location
The project area is located in a developed area of the Town of Fairfax in Marin County (Figure 1).
The project site is located on Creek Road between Wessen Road and Bolinas Road, and includes Town right-of-way and portions of Assessor Parcel Number (APN) 002-024-03, 002-024-04 and 002-024-23 (Figure 2). The project area encompasses the Creek Road Bridge (California Department of Transportation [Caltrans] Bridge No. 27C-0144) over San Anselmo Creek, which was constructed in 1929 (Figure 3). To perform the retrofit construction work, bridge areas and Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 6 components in the creek need to be accessed. Access to the creek would likely be from Wessen Lane, located adjacent to the bridge.
2.5 General Plan Designation and Zoning District
2.5.1 General Plan Designation
• Residential 1-6 du/acre
2.5.2 Zoning District
• RD -5.5-7 Residential
The project is located with a single-family residential neighborhood. The project is entirely surrounded by single family residential land uses (Figure 4). San Anselmo Creek and its channel is the only other land use present within the immediate vicinity of the project area.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 7 Figure 1. Project Site Regional Location
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 8 Figure 2. Aerial Photograph of the Project Site
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 9 Figure 3. Views of the Project Site
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 10 Figure 4. Views of Surrounding Land Uses
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 11 3.0 PROJECT DESCRIPTION
3.1 Project Background and Purpose
Much of the bridge infrastructure in the Town of Fairfax is of an older vintage, dating back 80 to 90 years. The Creek Road Bridge (Caltrans Bridge No. 27C-0144) over San Anselmo Creek was constructed in 1929 and needs a seismic retrofit. The purpose of the project is to retrofit Creek Road Bridge in order to enhance seismic safety, to prevent catastrophic failure during a Maximum Credible Earthquake (defined as the largest possible earthquake that could occur in a specific region, based on geological and seismological evidence, such as the length of active faults), and, overall, maintain the structural integrity of the bridge in the interests of public safety.
3.2 Detailed Description of the Project
Creek Road Bridge is a 4-span reinforced concrete structure, made up of four sets of reinforced concrete T-girders per span. The interior spans are supported on three sets of 2-column bents (structural components, often called a pier, that support the bridge deck at intermediate points along its length) in the creek and the exterior spans are connected to an abutment at each end of the bridge. There are no as-built plans available for the Creek Road Bridge, but an as-built bridge General Plan and additional structural detail sheets have been prepared for this project.
During the New Year’s Eve flood of 2005, the bridge’s west abutment experienced a major washout. The abutment was repaired and protected with rock riprap after a closure period.
Travelers utilized other streets as a detour around the closure during the repair period. In September 2010, a Scour Plan of Action Report was prepared, which is an evaluation required by the Federal Highway Administration for managing bridges that are vulnerable to failure from flooding. No new significant bridge foundation scour was identified around the bridge foundations.
The bridge is composed of a series of simple spans, supported by concrete cap beams (horizontal beams that sit atop bridge piers or columns to support the bridge deck and transfer loads from the superstructure to the substructure) on 2-column bents. This configuration is one of the vulnerabilities of the bridge. Since the superstructure spans are not connected to the substructure, they have the potential of unseating and collapsing during the movements induced by large seismic events. In the initial design phase of the project, structural analyses confirmed the seismic vulnerability of the bridge. Due to its seismic vulnerabilities, the bridge has been labeled as a Category 1 Bridge, implying that it would fail catastrophically under the Maximum Credible Earthquake, potentially resulting in the loss of life.
Further, it was concluded during the development of the seismic retrofit strategy for the bridge that, even if the spans were attached to the substructure of the bridge to prevent them from unseating during a seismic event, the entire substructure would still collapse due to the longitudinal movement and the momentum of the superstructure. Therefore, the bridge substructure must be retrofitted as well.
Retrofit concepts and costs to address the bridge’s seismic deficiencies were presented in a Seismic Retrofit Report prepared and submitted to Caltrans. For retrofit repairs, Caltrans Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 12 approved Alternate 2 of the Seismic Retrofit Strategy Report. The construction details for Alternative 2 can be found in Figure 5. The Caltrans philosophy of retrofit design for a nonlifeline facility, such as Creek Road Bridge, is to prevent its catastrophic failure and the loss of life. The bridge may sustain extensive damage, or even be inoperable after the quake, but must not collapse or endanger lives.
3.3 Project Construction
3.3.1 Construction Schedule
Construction work would occur over one dry season (usually April 15 through October 15) for work in the creek, when the flows are minimal, plus possibly a few weeks at each end of this period for the work above at the street level. Overall work duration is expected to last for approximately eight months.
3.3.2 Site Access and Staging
To perform the retrofit construction work, bridge areas and components in the creek would need to be accessed. Access to the creek would be provided by lowering equipment, containers, and materials from the bridge deck using a crane. Construction equipment would include smaller wheeled vehicles and hand-held devices. A crane, pickup trucks, dump trucks, concrete delivery trucks, small loaders, excavators and generators would be present at the project site daily. The construction vehicles would be in and out of the work area on a steady basis but may not all be present at the same time. Storage of constructions materials, tools and vehicles would be limited to areas within the Town’s right-of-way. Worker access to the creek would be over a footpath from the creek bank at either abutment.
The footprint of the bridge and approach roadways would not change in the process of the seismic retrofit and no new right-of-way for this work is needed. However, the bridge currently appears to occupy a narrow strip of land from an adjacent property on the upstream side (30 Creek Road; APN 002-024-04), as well as a small corner of the property at 12 Creek Road (APN 002-24-23). For these reasons, it is anticipated that the project would require permanent easements on both properties. In addition, temporary construction easements would be needed at 30 Creek Road and 12 Creek Road to access the creek and conduct the seismic retrofit work.
Pedestrian and vehicular access to homes would be maintained at all times.
3.3.3 Site Work
The bridge would be closed for the duration of construction and traffic would be detoured to other access routes. Detours to and away from the bridge site would be available via Creek Road and Porteous Avenue in the direction away from the bridge toward Bolinas Road.
Site work would consist of the following:
1. Site preparation would begin by implementing a dewatering plan that protects aquatic resources. Where needed, the flow would be diverted around the work area by building a cofferdam upstream of the location and bypassing flowing water through a diversion pipe, keeping turbidity to a minimum. Best Management Practices (BMPs) would be implemented to avoid the migration of the sediments or contaminants into the water flow areas or drainage systems.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 13 2. Infill walls would be constructed between each pair of columns at each of the three bridge bents in the creek. First, soils would be excavated at the bridge supports and would be lifted and stored above at the project site, likely on Wessen Lane. Excavated soils would be stored, covered, and used for backfilling after the retrofit work is complete. Groundwater intrusion into the work area would be pumped out into special containers, filtered, and placed back in the creek. Localized excavations would be required around three existing bridge bents (Bents 2, 3, and 4) to facilitate the installation of infill walls. The exact excavation configuration (i.e., fully shored versus partially sloped sidewalls) would be determined by the contractor; therefore, the larger potential excavation footprints are conservatively assumed for environmental analysis.
At Bent 4, excavation would disturb an area of up to approximately 23 feet by 8 feet at the surface. At Bent 2 and Bent 3, excavations would be larger due to the presence of existing riprap, with maximum disturbance areas of approximately 35 feet by 15 feet and 40 feet by 15 feet, respectively.
Excavated areas at Bents 2 and 3 would be backfilled with a base layer of rock (approximately 2.5 feet thick), overlain by native materials previously excavated and stockpiled on site.
3. At each bent, holes would be drilled into opposing column faces and fitted with epoxycoated steel dowels. Reinforcing steel would then be installed to form a structural cage between columns, followed by placement of formwork and pouring of reinforced concrete infill walls extending from the top of the footings to the underside of the cap beam. This retrofit would effectively convert the existing two-column bents into solid wall sections to improve seismic performance. In addition, seismic restrainer cables would be installed by drilling horizontal holes through the bridge diaphragms and cap beams. Steel cables would be threaded through these elements, wrapped around the cap beams, and anchored to secure the superstructure to the substructure, thereby reducing the potential for structural unseating during a seismic event. Concrete placement would be conducted in a manner that prevents discharge to the creek and avoids contact between wet concrete and creek water or groundwater. In addition, reinforced concrete shear keys (stoppers) would be installed on the faces of the bent caps using epoxy-anchored dowels and reinforcing steel to limit lateral and longitudinal movement of the superstructure and provide additional resistance to unseating during seismic events
4. Following construction, excavated areas at Bents 2 and 3 would be backfilled with a base layer of rock riprap (approximately 2.5 feet thick), overlain with native soils to match existing creek bed elevations. At Bent 4, excavations would be backfilled with native soil only.
5. Additional improvements would include repair of deteriorated concrete elements throughout the bridge, including the underside of the deck, girders, columns, and bent cap beams. Repairs would consist of removing unsound concrete, cleaning exposed reinforcement, and applying grout or similar materials to restore structural integrity. This work would be conducted from scaffolding or lifts, with measures in place to prevent construction materials from contacting the creek bed or flowing water.
6. At both abutments, excavation of the approach roadways would occur to construct reinforced concrete “waffle slabs” designed to anchor the bridge and limit seismic Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 14 movement. Excavations would be three feet deep for a distance of 20 feet away from the ends of the bridge, with a width matching the bridge width. The waffle slabs would be backfilled with compacted soil and topped with a concrete riding surface. Construction may require relocation of existing utilities, including waterlines, and modification of an existing storm drain system. If needed, the utilities would be relocated by the Marin Municipal Water District (MMWD). An existing 12-inch diameter corrugated metal pipe storm drain crossing Creek Road and daylighting at the south creek bank would be abandoned in place and rerouted, and associated trenching and repaving would occur.
Riprap would be placed at the storm drain outlet to stabilize the creek bank and prevent erosion.
7. In addition, the bridge deck would be rehabilitated by removing existing asphalt, repairing localized concrete deficiencies, sealing cracks, and replacing expansion joint seals.
At the end of the dry season all equipment, materials and temporary access ramps will be removed from the creek and the banks and creek would be restored. Upon the completion of the work in the creek, plant restoration and mitigation work would be implemented. Vegetation disturbed by or removed for construction would be replaced. The approach roadways pavement excavated for waffle slab construction would be tidied up and restriped and the road would be opened for travel.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 15 Figure 5. Creek Road Bridge Seismic Retrofit Details Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 16 3.4 Project–Related Approvals, Agreements, and Permits The information contained in this Initial Study will be used by the Town of Fairfax (the CEQA Lead Agency) as it considers whether to approve the proposed project. If the project is approved, the Initial Study, as well as the associated Mitigated Negative Declaration would be used by the Town and responsible and trustee agencies in conjunction with various approvals and permits.
These actions include, but may not be limited to, the following approvals by the agencies indicated below.
3.4.1 Army Corps of Engineers
• Clean Water Act Section 404 Form 4345, Application for Department of the Army Permit
3.4.2 California Department of Fish and Wildlife
• Section 1602 Lake and Streambed Alteration Agreement
3.4.3 Regional Water Quality Control Board
• Clean Water Act, Application for Section 401 Water Quality Certification • Notice of Intent under the State Construction General NPDES Permit Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 17 4.0 ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED
The environmental factors checked below would be potentially affected by this project, involving at least one impact that is potentially significant unless mitigation is incorporated, as indicated by the checklist on the following pages.
Aesthetics Greenhouse Gas Emissions Public Services
Agricultural Resources Hazards and Hazardous Materials Recreation Air Quality Hydrology and Water Quality Transportation
Biological Resources Land Use/Planning Tribal Cultural Resources Cultural Resources Mineral Resources Utilities / Service Systems Energy Noise Wildfire
Geology and Soils Population and Housing Mandatory Findings of Significance
4.1 Determination
On the basis of this initial evaluation:
I find that the project COULD NOT have a significant effect on the environment and a NEGATIVE DECLARATION will be prepared.
I find that although the project could have a significant effect on the environment, there will not be a significant effect in this case because revisions in the project have been made by or agreed to by the project proponent. A MITIGATED NEGATIVE DECLARATION will be prepared.
I find that the project MAY have a significant effect on the environment, and an ENVIRONMENTAL IMPACT REPORT is required.
I find that the project MAY have a “Potentially significant impact” or “potentially significant unless mitigated” impact on the environment, but at least one effect 1) has been adequately analyzed in an earlier document pursuant to applicable legal standards, and 2) has been addressed by mitigation measures based on the earlier analysis as described on attached sheets. An ENVIRONMENTAL IMPACT REPORT is required, but it must analyze only the effects that remain to be addressed.
I find that although the project could have a significant effect on the environment, because all potentially significant effects (a) have been analyzed adequately in an earlier EIR or NEGATIVE DECLARATION pursuant to applicable standards, and (b) have been avoided or mitigated pursuant to that earlier EIR or NEGATIVE DECLARATION, including revisions or mitigation measures that are imposed upon the proposed project, nothing further is required.
_________________________________________ __________________ Signature Date
Name and Title: Kristin Arnold, Public Works Director
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Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 18 4.2 Initial Study Checklist
This section describes the existing environmental conditions in and near the project site and evaluates environmental impacts associated with the proposed project. The environmental checklist, as recommended in the CEQA Guidelines (Appendix G), was used to identify environmental impacts that could occur if the proposed project is implemented.
Each of the environmental categories was fully evaluated, and one of the following four determinations was made for each checklist question:
“No Impact” means that no impact to the resource would occur as a result of implementing the project.
“Less than Significant Impact” means that implementation of the project would not result in a substantial and/or adverse change to the resource, and no mitigation measures are required.
“Less than Significant with Mitigation Incorporated” means that the incorporation of one or more mitigation measures is necessary to reduce the impact from potentially significant to less than significant.
“Potentially Significant Impact” means that there is either substantial evidence that a project-related effect may be significant, or, due to a lack of existing information, could have the potential to be significant.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 19 4.2.1 Aesthetics
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Have a substantial adverse effect on a
scenic vista?
b) Substantially damage scenic resources,
including, but not limited to, trees, rock
outcroppings, and historic buildings within a
state scenic highway?
c) In non-urbanized areas, substantially
degrade the existing visual character or
quality of public views of the site and its
surroundings? (Public views are those that
are experienced from publicly accessible
vantage point). If the Project is in an
urbanized area, would the Project conflict
with applicable zoning and other regulations
governing scenic quality?
d) Create a new source of substantial light or
glare which would adversely affect day or
nighttime views in the area?
ENVIRONMENTAL SETTING
The project site is located within the Town of Fairfax, within a residential neighborhood adjacent to Bolinas Road and Dominga Avenue. The Creek Road Bridge is approximately 0.3 miles from the downtown center of Fairfax. At the site, the bridge spans approximately 130 feet over San Anselmo Creek.
Views of the project site are generally limited to the surrounding residential homes and streets, from residents, motorists, and pedestrians along portions of Creek Road, Dominga Avenue, and Wessen Lane. The project is entirely surrounded by single family residential land uses. San Anselmo Creek and its channel is the only other land use present within the immediate vicinity of the project area. Dense vegetation along the banks of San Anselmo Creek is visible from the project site and the trees within the creek bed shield most of the view looking southeast along the bridge towards Creek Road.
The proposed project site is located within Marin County which does not have any officially designated state or county scenic highways (Caltrans 2018). The nearest eligible state highway is Highway 37, approximately three miles northeast of the project site. The bridge is not considered historic and has a value of 5 for Historical Significance (National Bridge Inventory [NBI], Item No. 37).
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 20 DISCUSSION OF IMPACTS
a) Have a substantial adverse effect on a scenic vista? Less-than-Significant Impact
For the purposes of this analysis, a scenic vista is defined as a vantage point with a broad and expansive view of a significant landscape feature (e.g., a mountain range, the Bay, lake, or coastline) or of a significant historical or architectural feature (e.g., views of a historic tower).
Under this definition, there are no scenic vistas viewable from the project site. Views from public locations (i.e., views from residential streets, etc.) would not be significantly altered or obstructed as a result of the proposed bridge repairs. The project would have a less than significant impact regarding scenic vistas.
b) Substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings within a state scenic highway? Less-than-Significant Impact
The project site is not within the vicinity of a state scenic highway. No rock outcroppings or similar recognized visual resources exist on the site, and none would be damaged through construction of the proposed project. The proposed project would not significantly alter preconstruction conditions. Views from viewer superior positions (i.e., views looking down at the project area from higher elevations such as a second story home), also would not be significantly altered as a result of the proposed project because the project’s proposed bridge repairs would be below the sightline of the homes and would not stand out in comparison to existing conditions. Therefore, the project would have a less-than-significant impact on these resources. c) In non-urbanized areas, substantially degrade the existing visual character or quality of public views of the site and its surroundings? If the project is in an urbanized area, would the project conflict with applicable zoning and other regulations governing scenic quality?
Less-than-Significant Impact
The project site is located in a single-family residential portion of an urban area. The site is zoned for residential use. During the construction phase, views of the material stored in the proposed project site, construction equipment, and stockpiled soil would be available for brief periods. Storage of constructions materials, tools and vehicles will be limited to Wessen Lane and locations within the APE. The activities are typical of seismic retrofit strategies approved by Caltrans in developed areas and would not substantially degrade views of the existing setting.
The removal of soil from the creek at the bridge supports would be stored above the project site within the designated staging/stockpile area that would be screened from public view via existing vegetation. This placement would be temporary, and the soil would be used for backfill later.
Views from public locations (i.e., views from residential streets, etc.) would not be substantially degraded as a result of the proposed seismic retrofit strategy. Upon the completion of the work in the creek, plant restoration and mitigation work will be implemented. Vegetation disturbed by or removed for construction will be replaced. The approach roadways pavement excavated for waffle slab construction will be tidied up and restriped and the road will be opened for travel.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 21 Therefore, views would be similar to existing conditions and impacts would be less than significant.
d) Create a new source of substantial light or glare which would adversely affect day or nighttime views in the area?
Less-than-Significant Impact
The project would not create a new permanent source of light or glare. The proposed project would involve seismic retrofit of an existing bridge and no nighttime construction would be required. The project would not create a new source of substantial light or glare which would adversely affect day or nighttime views in the area and impacts would be less than significant.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 22 4.2.2 Agricultural and Forestry Resources1
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
LessthanSignificant
Impact
No
Impact
a) Convert Prime Farmland, Unique Farmland, or
Farmland of Statewide Importance (Farmland),
as shown on the maps prepared pursuant to the
Farmland Mapping and Monitoring Program of
the California Resources Agency, to nonagricultural use? b) Conflict with existing zoning for agricultural use,
or a Williamson Act contract?
c) Conflict with existing zoning for, or cause
rezoning of, forest land (as defined in Public
Resources Code section 12220(g)), timberland
(as defined by Public Resources Code section
4526), or timberland zoned Timberland
Production (as defined by Government Code
section 51104(g))?
d) Result in the loss of forest land or conversion of
forest land to non-forest use?
e) Involve other changes in the existing
environment, which, due to their location or
nature, could result in conversion of Farmland,
to non-agricultural use or conversion of forest
land to non-forest use?
ENVIRONMENTAL SETTING
The project site does not contain any farmland or forestry land and is not designated for agricultural or forestry uses or Prime, Statewide, or Locally Important Farmland (California Department of Conservation [CDOC] 2022a). The proposed project is located in a semideveloped area and follows existing roads, easements, and rights-of-way. Surrounding land is developed with residential uses.
1 In determining whether impacts to agricultural resources are significant environmental effects, lead agencies may refer to the California Agricultural Land Evaluation and Site Assessment Model (1997) prepared by the California Dept. of Conservation as an optional model to use in assessing impacts on agriculture and farmland. In determining whether impacts to forest resources, including timberland, are significant environmental effects, lead agencies may refer to information compiled by the California Department of Forestry and Fire Protection regarding the state’s inventory of forest land, including the Forest and Range Assessment project and the Forest Legacy Assessment project; and forest carbon measurement methodology provided in Forest Protocols adopted by the California Air Resources Board.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 23 DISCUSSION OF IMPACTS
a) Convert Prime Farmland, Unique Farmland, or Farmland of Statewide Importance (Farmland), as shown on the maps prepared pursuant to the Farmland Mapping and Monitoring Program of the California Resources Agency, to non-agricultural use? No Impact
According to the 2010 Farmland Mapping and Monitoring Program from the CDOC, the project site is located in an area that is designated as urban and built-up land and the proposed project would, therefore, have no impact on agricultural uses. No impact would occur. b) Conflict with existing zoning for agricultural use, or a Williamson Act contract? No Impact
According to the CDOC’s Williamson Act Enrollment Finder, the project site is not designated as being under a Williamson Act Contract, nor is it zoned for an agricultural use (CDOC 2022b).
Therefore, no impact would occur.
c) Conflict with existing zoning for, or cause rezoning of, forest land (as defined in Public Resources Code Section 12220(g)), timberland(as defined by Public Resources Code Section 4526), or timberland zoned Timberland Production (as defined by Government Code Section 51104(g))?
No Impact
The project site is zoned RD -5.5-7 Residential. Therefore, it would not conflict with the existing zoning for or cause rezoning of forest land, timberland, or timberland zoned Timberland Production. No impact would occur.
d) Result in a loss of forest land or conversion of forest land to non-forest use? No Impact
The proposed project site is within a residential area. There is no forest land at or around the site and therefore would not result in a loss or conversion of forest land to a non-forest use. e) Involve other changes in the existing environment which, due to their location or nature, could result in conversion of Farmland to non-agricultural use or conversion of forest land to non-forest use?
No Impact
The proposed project involves the construction and maintenance of existing infrastructure within an already developed area that does not include any farmland. Therefore, the proposed project would not result in the conversion of forest land or farmland to a non-forest use or a nonagricultural use and would thus have no impact on forestry or agricultural resources.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 24 4.2.3 Air Quality
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
LessthanSignificant
Impact
No
Impact
a) Conflict with or obstruct implementation of the
applicable air quality plan?
b) Result in a cumulatively considerable net
increase of any criteria pollutant for which the
project region is in non-attainment under an
applicable federal or state ambient air quality
standard?
c) Expose sensitive receptors to substantial
pollutant concentrations?
d) Result in other emissions (such as those leading
to odors) affecting a substantial number of
people?
ENVIRONMENTAL SETTING
The proposed project is located in the San Francisco Bay Area Air Basin (SFBAAB) which is within the jurisdiction of the Bay Area Air District (BAAD). Air quality in this area is determined by such natural factors as topography, meteorology, and climate, in addition to the presence of existing air pollution sources and ambient conditions. The potential for high pollutant concentrations developing at a given location depends upon the quantity of pollutants emitted into the atmosphere in the surrounding area or upwind, and the ability of the atmosphere to disperse the contaminated air.
The project site is located in the eastern portion of Marin County, which is bounded on the west by the Pacific Ocean, on the east by San Pablo Bay, on the south by the Golden Gate, which connects San Francisco Bay to the Pacific Ocean, and on the north by the Petaluma Gap, which is a geographical region in Sonoma County which extends in a band from the Pacific Ocean to San Pablo Bay. Air pollution potential is highest in eastern Marin County, where most of population is located in semi-sheltered valleys. In the southeast, the influence of marine air keeps pollution levels low. As development moves further north, there is greater potential for air pollution to build up because the valleys are more sheltered from the sea breeze.
While Marin County does not have many polluting industries, the air quality on its eastern side - especially along the U.S. 101 corridor - may be affected by emissions from increasing motor vehicle use within and through the county. Sources of air pollutants in the nearby vicinity of the project area include vehicle emissions and other residential activities (cooking, wood burning, and charcoal grilling; emissions associated with lawn and garden maintenance; emissions associated with application of paints and coatings; etc.). The primary sensitive receptors in the vicinity are residents, which may include children, elderly people, or people with respiratory illnesses.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 25 Both US EPA and California have developed several ambient air quality standards (AAQS) which have become increasingly stringent over the last several decades. Although emissions and air pollution concentrations have decreased considerably, the SFBAAB is still classified as “nonattainment” with respect to standards for ozone (O3)—most of which is formed in the atmosphere by chemical reactions between reactive organic gases (ROG) and oxides of nitrogen (NOx) rather than being emitted directly—and particulate matter (PM). The Basin is considered “non-attainment” for the O3 (1-hour and 8-hour), PM10 (24-hour and AAM) and PM2.5 (AAM) state standards.
For the proposed project, the only sources of emissions are those associated with construction; i.e., the proposed project does not involve the construction of a new air emissions source, or of developments which would attract motor vehicles with their associated air emissions. New construction equipment has been subject to increasingly stringent emissions requirements at the Federal level (e.g., 40 CFR 89 and 1039), designated “Tier 1”, “Tier 2”, “Tier 3”, etc.; older construction equipment is subject to potential retrofit requirements required by the State of California (13 CCR 2449, 13 CCR 2450-2466, and 17 CCR 93116).
There are multiple definitions of what emissions level would be considered “significant”. If a large (“major”) stationary source of air pollution were proposing to locate at the project area, Federal New Source Review (NSR) regulations define “significant” emissions as being 100 tons per year (TPY) of CO or 40 TPY of ROG or NOx.
2 For temporary activities at the project area such
as construction, if the project required Federal support or approvals, General Conformity regulations would require a quantitative, formal determination of General Conformity with State Implementation Plans (SIPs) if emissions of NOx, ROG, or CO were in excess of 100 tons per year (referred to as Federal de minimis levels).3
DISCUSSION OF IMPACTS
a) Conflict with or obstruct implementation of the applicable air quality plan? Less-than-Significant Impact with Mitigation Incorporated The most recent air quality plan for the project site is the 2017 Clean Air Plan (CAP) (BAAD 2017). The CAP identifies ways to improve the air quality within the Bay Area. While the proposed project would result in a temporary increase in emissions during the construction phase, the following best management practices (BMPs), recommended by the BAAD CAP would be implemented. Therefore, due to the small area of disturbance, the temporary nature of emissions, and the implementation of the following mitigation, a less than significant impact would occur related to obstructing or conflicting with the CAP.
Mitigation Measure AIR-1. Fugitive Dust Control Measures The BAAD recommends basic construction measures to ensure minimal impacts on regional air quality. The contractor shall be responsible for implementing the following basic measures:
2 40 CFR 51.165(a)(1)(x)(A); 51.166(b)(23)(i); 52.21(b)(23). 3 Separately, Federal regulations for General Conformity identify “routine maintenance and repair activities, including repair and maintenance of administrative sites, roads, trails, and facilities” as “actions which would result in...an increase in emissions that is clearly de minimis” [40 CFR 93.153(c)(2)(iv)]
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 26 • All exposed surfaces (e.g., parking areas, staging areas, soil piles, graded areas) shall be watered two times per day, as appropriate; pave, apply water three times daily, or apply (non-toxic) soil stabilizers on all unpaved access roads, parking area and staging areas.
• All paved access roads, parking areas and staging areas at the construction site shall be swept daily with water sweepers. All visible mud or dirt track-out onto adjacent public roads shall be removed using wet power vacuum street sweepers at least once per day. The use of dry power sweeping is prohibited.
• Idling times shall be minimized either by shutting equipment off when not in use or reducing the maximum idling time to 5 minutes (as required by the California airborne toxics control measure Title 13, Section 2485 of California Code of Regulations). Clear signage shall be provided for construction workers at all access points. • All construction equipment shall be maintained and properly tuned in accordance with manufacturer‘s specifications, and all equipment shall be checked by a certified visible emissions evaluator.
• A publicly visible sign with the telephone number and person to contact at the lead agency regarding dust complaints shall be posted in or near the project area. The contact person shall respond to complaints and take corrective action within 48 hours. The BAAD’s phone number shall also be visible to ensure compliance with applicable regulations.
b) Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is non-attainment under an applicable federal or state ambient air quality standard?
Less-than-Significant Impact
As mentioned in the Environmental Setting, the project area is non-attainment with respect to AAQS for ozone and particulate matter. The BAAD 2017 Clean Air Plan addresses these AAQS and evaluates cumulative impacts by considering emissions from all sources and projecting future activity. As described above in response to questions 4.3 (a) and (b), the emissions from the proposed project are negligible compared with other emissions in the air basin and are also temporary in nature. After implementation of the BMPs, the temporary increase in air pollutant emissions associated with construction activities would result in less than significant contributions to cumulative pollutant levels in the region. c) Expose sensitive receptors to substantial pollutant concentrations? Less-than-Significant Impact with Mitigation Incorporated The primary sensitive receptors in the vicinity are residents, which may include children, elderly people, or people with respiratory illnesses. Sensitive receptors are located in close proximity to several locations along the construction area. However, construction activities would be limited to the bridge area, fugitive dust will be minimized (per the BMPs listed above), and construction equipment is mobile (dispersing and diluting pollutants over a wider area than if they were fixed in place). New construction equipment has been subject to increasingly stringent emissions requirements at the Federal level (e.g. 40 CFR 89 and 1039), designated “Tier 1”, “Tier 2”, “Tier 3”, etc.; older construction equipment is subject to potential retrofit requirements required by the Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 27 State of California (13 CCR 2449, 13 CCR 2450-2466, and 17 CCR 93116). Basic construction air quality measures as recommended in Mitigation Measure AIR-1 would be implemented throughout project construction. These measures would reduce dust generation and construction equipment emissions. As a result, sensitive receptors in the vicinity of the proposed project would not be exposed to substantial pollutant concentrations, and impacts would be less than significant.
d) Result in other emissions (such as those leading to odors) adversely affecting a substantial number of people?
Less-than-Significant Impact
BAAD’s CEQA Guidelines identify the following as potential sources of objectionable odors:
wastewater treatment plants, landfills, confined animal facilities, composting stations, food manufacturing plants, refineries, and chemical plants. The proposed project does not involve construction of any of those types of facilities. Construction activities would involve the use of diesel-powered equipment that emits exhaust gases and particulate matter, which can emit pollutants that have objectionable odors. However, construction equipment is mobile (dispersing and diluting pollutants over a wider area than if they were fixed in place). Therefore, odorcreating emissions related to the project would not adversely affect a substantial number of people. Thus, a less than significant impact would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 28 4.2.4 Biological Resources
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
LessthanSignificant
Impact
No
Impact
a) Have a substantial adverse effect, either
directly or through habitat modifications, on
any species identified as a candidate,
sensitive, or special-status species in local or
regional plans, policies, or regulations, or by
the California Department of Fish and Game or
U.S. Fish and Wildlife Service?
b) Have a substantial adverse effect on any
riparian habitat or other sensitive natural
community identified in local or regional plans,
policies, or regulations or by the California
Department of Fish and Game or U.S. Fish and
Wildlife Service?
c) Have a substantial adverse effect on state or
federally protected wetlands (including, but
not limited to, marsh, vernal pool, coastal,
etc.) through direct removal, filling,
hydrological interruption, or other means?
d) Interfere substantially with the movement of
any native resident or migratory fish or wildlife
species or with established native resident or
migratory wildlife corridors, or impede the use
of native wildlife nursery sites?
e) Conflict with any local policies or ordinances
protecting biological resources, such as a tree
preservation policy or ordinance?
f) Conflict with the provisions of an adopted
Habitat Conservation Plan, Natural Community
Conservation Plan, or other approved local,
regional, or state habitat conservation plan?
ENVIRONMENTAL SETTING
The analysis of potential biological impacts is based on the Natural Environment Study (NES) (Appendix A) and Biological Assessment (BA) (Appendix B) prepared for the proposed project.
Kelly Biological Consulting and WRA, Inc. (WRA) jointly prepared the NES and BA, which were approved by Caltrans. The documents jointly outline vegetation communities present, suitability of on-site habitat for special-status plant and wildlife species, and the presence of jurisdictional wetlands and “other waters”. The studies were conducted through a combination of seven site Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 29 visits and a review of databases and available literature within the proposed Biological Study Area (BSA).
The project site encompasses the Creek Road Bridge over San Anselmo Creek in the Town of Fairfax, Marin County, California. Site elevations range from approximately 100‐150 feet and surrounding land uses are primarily residential. Most of the creek bank (below the top of bank) is densely vegetated with English ivy, California blackberry, and Himalayan blackberry. Unvegetated areas are bare dirt or are covered with large rock riprap. With the exception of one small gravel bar, the creek bed is generally unvegetated.
The principal natural hydrological sources for the project site are creek flows, direct precipitation and surface run-off from adjacent lands. San Anselmo Creek flows though the project site towards the north/northeast. Just north of the project site, Deer Creek joins San Anselmo Creek.
Roughly one quarter of a mile to the north, it joins Fairfax Creek and turns east, eventually flowing into Corte Madera Creek, then San Francisco Bay, and the Pacific Ocean. In wet years, the creek at this location is perennial. At the time of the fieldwork, in a drought year, the flows were low.
Biological Study Area
The BSA is located on and around the Creek Road Bridge over San Anselmo Creek in the Town of Fairfax, Marin County, California. The BSA covers all areas where direct and indirect impacts would occur such as ground-disturbance, construction staging, access roads, and noise disturbances. The BSA is extended beyond areas of the proposed project footprint or direct impacts to ensure that key biological issues are addressed. Creek Road is a local road in a developed area. The adjacent land use is residential (single family homes). The BSA extends up and downstream from the bridge along the stream corridor covering the only natural area.
Site elevations range from approximately 100 to 150 feet NAVD88. The bridge is located on the San Rafael USGS 7.5-minute quadrangle map at latitude W37.585932, longitude N122.352612.
Natural Communities
Riparian Woodland
The BSA consists of a mature closed canopy Riparian Woodland similar to California Bay (Umbellularia Californica) Forest Alliance. The Riparian Woodland community is considered a natural community of special concern (sensitive). Overstory species include native tree species such as big-leaf maple (Acer macrophyllum), California bay, and California walnut (Juglans californica). The understory is comprised mainly of California blackberry (Rubus ursinus), Himalayan blackberry (Rubus armeniacus), English ivy (Hedera helix), and various grasses including panic veldtgrass (Ehrharta erecta) and wall barley (Hordeum murinum ssp. murinum).
Several small diameter white alders (Alnus rhombifolia), big-leaf maples, a young buckeye (Aesculus californica), and some sparse arroyo willow (Salix lasiolepis) (planted during 2005 bank work) make up the shrub and tree part of the understory. The small, scattered alders and willows are indicative of a riparian community. In the project site, the community would be considered a woodland rather than a riparian zone because of the scattered and sparse occurrence of these species.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 30 Ruderal Disturbed/Developed
The Ruderal Disturbed/Developed portions of the BSA include the roadsides, landscaping, gravel and bare dirt areas, as well as paved areas and structures. Within the project side, this plant community is predominately non-native herbaceous species commonly found in the region, such as sorrel (Oxalis incarnata and O. pes-carpe), narrow-leaved vetch (Vicia sativa ssp. nigra), various clovers (Trifolium spp.), wild oats (Avena fatua), ripgut brome (Bromus diandrus), and Canary reed-grass (Phalaris canariensis). The roadside vegetation includes a small stand of coyote brush (Baccharis pilularis) on the northern top of bank.
Perennial Stream (Comprised of “Other Waters” and Wetlands) San Anselmo Creek is a perennial creek with flows that vary with the rainfall patterns of a given season. The watershed that supports it is a local area, primarily the western part of the Town of Fairfax and adjacent open space lands. Flows within the creek at the time of the site visit in the spring of 2015 were low; only a few inches of water remained within a low flow channel that narrowed to several feet in places, though several deeper pools persist year-round in the BSA.
Wrack observed at the edge of the creek bed was used as an indication of Ordinary High Water Mark (OHWM). Creek substrate consists of small gravel to larger cobble. The channel width at the OHWM was used to determine the “other waters” boundary. The creek is not included on the National System of Wild and Scenic Rivers published by the U.S. Department of the Interior.
A 7-foot by 3-foot wetland area occurs on a gravel bar within the creek bed. The dominant vegetation found here includes hoita (Hoita macrostachya), fig (Ficus carica), alder (Alnus rhombifolia), and Himalayan (aka Armenian) blackberry (Rubus armeniacus) (FACU). The soils are silty sand with 1-3 inches cobble and a chroma of 10YR3/2.
Pursuant to the Clean Water Act Section 404 and 401 the creek below OHWM including the wetland would be within the U.S. Army Corps. of Engineers (Corps) and Regional Water Quality Control Board (RWQCB) jurisdiction. These areas are also considered Waters of the State per the Porter-Cologne Water Quality Control Act. There are no areas within the BSA that would be considered Waters of the State that are not Waters of the US. The portion of the creek channel that is vegetated with hydrophytic species is a jurisdictional wetland the rest is “other waters”. In total, <0.001 acre (20 square feet, approximately 25 linear feet) of permanent impacts and 0.075 acre (3,265 square feet, approximately 275 linear feet) of temporary impact to potentially jurisdictional “other waters” (creek bed) are proposed. The proposed project would result in less than 0.001 acre (22 square feet) of temporary impacts and no permanent impacts to wetlands.
Unvegetated Bank
The banks under the existing bridge are generally unvegetated. The western bank consists of rock riprap. The eastern bank is made up of exposed bedrock and bare dirt.
Special-Status Species
Database searches indicate that 76 special-status plant species and 101 special-status wildlife species have been documented in or have a range that occurs in the San Rafael, Bolinas, San Geronimo, Novato, Petaluma Point, San Quentin, San Francisco North, or Point Bonita 7.5-minute USGS quadrangles. Of these species, 31 special-status plant species and 13 special-status wildlife species have documented occurrences within 8 kilometers (5 miles) of the BSA.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 31 Special-Status Plant Species
Due to a lack of appropriate habitat elements (such as coastal salt marsh) and the presence of residential development in the surrounding landscape, the project site has the potential to support only 11 of the special-status plant species:
• Napa false indigo (Amorpha californica var. napensis, CNPS 1B.2). Woodland habitat within the project could support this species. However, this shrub species, which is easily identifiable, was not observed during the field surveys. • Bent-flowered fiddleneck (Amsinckia lunaris, BLMS, CNPS 1B.2). Woodland habitat within the project site could support this species. However, it may be too shady. This perennial species was not observed within the project site. If it was present, it would have been identified during the field surveys, which were conducted during the flowering period.
• Western leatherwood (Dirca occidentalis, CNPS 1B.2). Woodland habitat within the project site could support this species. However, this woody shrub species, was not observed during the field surveys, which were conducted during the flowering period. • Minute pocket moss (Fissidens pauperculus, USFSS, CNPS 1B.2). Mesic substrates within the project site could support this species. However, the site is not in coniferous forest, a typical requirement for this species. This species was not observed during the field surveys which occurred during the appropriate wet season. • Marin checker lily (Fritillaria lanceolata var. tristulis, CNPS 1B.1). Though not coastal, there is riparian habitat within the project site. No Fritillaria (a perennial bulbiferous herb) were observed during the field surveys, which were conducted during the flowering period.
• Diablo helianthella (Helianthella castanea, CNPS 1B.2, BLMS). The project site is disturbed, though has low quality habitat present. No Helianthella were observed during the field surveys, which were conducted during the flowering period. • Thin-lobed horkelia (Horkelia tenuiloba, CNPS 1B.2, BLMS). The only mesic soils within the project site are in the of the creek. These areas provide limited habitat for this species. Though high flows would likely damage plants. This species was not observed during the field surveys, which were conducted during the flowering period. • Marsh microseris (Microseris paludosa, CNPS 1B.2). Typically this species occurs in closed cone coniferous forest or cismontane woodland in mesic areas. The project site provides marginal disturbed habitat. However, this species was not observed during the field surveys, which were conducted during the flowering period. • North coast semaphore grass (Pleuropogon hooverianus, BLMS, ST, CNPS 1B.1). This species occurs in moist, open to shaded areas, broadleafed upland forest, meadows and seeps. The site provides marginal habitat, but high creek flows and seasonal drying of the creek bed limit the habitat. This species was not observed during the field surveys, which were conducted during the flowering period. • Tamalpais oak (Quercus parvula var. tamalpaisensis, CNPS 1B.3). Though, the project site provides woodland habitat, this species is a woody shrub, which would have been identifiable during the site visits. No shrubby oaks were observed during the field surveys.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 32 • Santa Cruz microseris (Stebbinsoseris decipiens, CNPS 1B.2). This species occurs in open areas in broadleafed upland forest and other habitats. The only open area is the top of the bank, which is heavily disturbed. Most of the vegetation found there was ruderal and non-native. This species was not observed during the field surveys, which were conducted during the flowering period.
The remaining special-status plant species documented in the vicinity are unlikely to occur in the project site based on lack of suitable habitats or specific substrates. No special-status plant species were observed within the project site during floristic surveys completed during the appropriate flowering periods. It is therefore unlikely that there are special-status plant species present within the project site.
Special-Status Wildlife Species
The BSA is designated as critical habitat for both Central California Coast (CCC) steelhead and Coho salmon (O. kisutch). Steelhead have been documented and are presumed present within this section of San Anselmo Creek. Coho salmon is considered extirpated because they no longer spawn or occur within tributaries and waters of San Francisco Bay. The project site is also listed as Essential Fish Habitat (EFH) for Coho salmon and Chinook salmon (O. tshawytscha); though neither species occurs in the watershed. In addition to steelhead, based on habitat and conditions within the project site and considering documented occurrences nearby, the project site has potential to support non-special status bird species and six other special-status wildlife species. These species are detailed below.
• Allen’s hummingbird (Selasphorus sasin, USFWS Bird of Conservation Concern). Allen’s hummingbird is found in a wide variety of habitats that provide nectar-producing flowers. The species is considered a common breeder throughout much of the San Francisco Bay area.
• Rufous hummingbird (Selasphorus rufus, USFWS Bird of Conservation Concern). The rufous hummingbird is a common migrant and uncommon summer resident in California. It occurs in a wide variety of habitats as long as they provide abundant nectar sources.
• Purple martin (Progne subis, CDFW Species of Special Concern). The purple martin is an uncommon summer resident in California, occurring in woodlands and lowelevation hardwood and coniferous forest. It usually feeds on insects captured in flight 100-200 feet above ground. The purple martin nests in cavities often located in tall, isolated trees or snags in open forest or woodland. • Olive-sided flycatcher (Contopus cooperi, CDFW Species of Special Concern, USFWS Bird of Conservation Concern). This species if found within the coniferous forest biome, most often associated with forest openings, forest edges near natural openings (e.g. meadows, canyons, or rivers) or human-made openings (e.g., harvest units), or open to semi-open forest stands (Altman 2000). • Oak titmouse (Baeolophus inornatus, USFWS Bird of Conservation Concern). This relatively common species is year-round resident throughout much of California including most of the coastal slope, the Central Valley and the western Sierra Nevada foothills. Its primary habitat is woodland dominated by oaks. Local populations have adapted to woodlands of pines and/or junipers in some areas (Cicero 2000). The oak titmouse nests in tree cavities, usually natural cavities or those excavated by Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 33 woodpeckers, though they may partially excavate their own (Cicero 2000). Seeds and arboreal invertebrates make up the birds’ diet.
• Nuttall’s woodpecker (Picoides nuttallii, USFWS Bird of Conservation Concern).
Nuttall’s woodpecker typically reside in lowland woodlands throughout California, west of the Sierra Nevada. This species is associated with intact oak and riparian woodlands, rarely in conifers, and is a primary cavity nester.
REGULATORY SETTING
Federal Regulations
Federal Endangered Species Act
The Endangered Species Act (ESA) of 1973, as amended (16 USC 1531 et seq.), was enacted to provide a means to identify and protect endangered and threatened species. Under Section 9 of the ESA, it is unlawful to take any listed species. “Take” is defined as harassing, harming, pursuing, hunting, shooting, wounding, killing, trapping, capturing, or collecting a listed species. “Harass” is defined as an intentional or negligent act or omission, which creates the likelihood of injury to wildlife by annoying it to such an extent as to significantly disrupt normal behavioral patterns, which include, but are not limited to, breeding, feeding, or sheltering. “Harm” is defined as an act which actually kills or injures fish or wildlife and may include significant habitat modification or degradation which actually kills or injures fish or wildlife by significantly impairing essential behavioral patterns, including breeding, spawning, rearing, migrating, feeding, or sheltering.
Actions that may result in “take” of a federal-listed species are subject to USFWS or National Marine Fisheries Service (NMFS) permit issuance and monitoring. Section 7 of ESA requires federal agencies to ensure that any action authorized, funded, or carried out by the agency is not likely to jeopardize the continued existence of any endangered or threatened species or result in the destruction or adverse modification of designated critical habitat for such species. Any action authorized, funded, or carried out by a federal agency or designated proxy (e.g., Caltrans) which has potential to affect listed species requires consultation with the USFWS or the NMFS under Section 7 of the ESA.
Clean Water Act (CWA)
The CWA provides guidance for the restoration and maintenance of the chemical, physical, and biological integrity of the nation's waters. Section 404 identifies the Corps’ jurisdiction over fill materials in essentially all water bodies, including wetlands. All federal agencies are required to avoid impacts to wetlands whenever there is a practicable alternative. Section 404 established a permit program administered by the Corps regulating the discharge of dredged or fill material into Waters of the US (including wetlands). Section 401 of the CWA requires that an applicant for a federal license or permit that allows discharge to Waters of the U.S. obtain a state certification that the discharge complies with the CWA. The Regional Water Quality Boards (RWQCB) administer the certification program in California. The guidelines allow the discharge of dredged or fill material into the aquatic system only if there is no practicable alternative that would have less adverse impacts.
Executive Order 11990 – Protection of Wetlands
This order established a national policy to avoid adverse impacts to wetlands whenever there is a practicable alternative. The U.S. Department of Transportation (DOT) promulgated DOT Order Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 34 5660.1A in 1978 to comply with this direction. On federally funded projects, impacts to wetlands must be identified. Alternatives to the Creek Road Bridge Seismic Retrofit that avoid wetlands therefore must be considered. If wetland impacts cannot be avoided, then all practicable measures to minimize harm must be included. This must be documented in a specific Wetlands Only Practicable Alternative Finding. An additional requirement is to provide early public involvement in projects affecting wetlands. The Federal Highway Administration (FHWA) provides technical assistance (Technical Advisory 6640.8A) and reviews environmental documents for compliance.
Migratory Bird Treaty Act
This treaty with Canada, Mexico, and Japan makes it unlawful at any time, by any means or in any manner, to pursue, hunt, take, capture, or kill migratory birds. The law applies to the removal of nests (such as swallow nests on bridges) occupied by migratory birds during the breeding season. California Fish and Game Code (Sec 3500) also prohibits the destruction of any nest, egg, or nestling.
State Regulations
California Porter-Cologne Water Quality Control Act
This regulatory law is becoming more prominent on projects involving impacts to isolated Waters of the State (non-404/401 waters). The RWQCB is increasingly requiring Waste Discharge Requirement (WDR) permits for impacts to Waters of the State.
Streams, Lakes, and Riparian Habitat in California
Streams and lakes, as habitat for fish and wildlife species, are subject to the jurisdiction of California Department of Fish and Wildlife (CDFW) under Sections 1600-1616 of California Fish and Game Code. Alterations to, or work within or adjacent to streambeds or lakes generally require a 1600 series Lake and Streambed Alteration Agreement. The term “stream”, which includes creeks and rivers, is defined in the California Code of Regulations (CCR) as “a body of water that flows at least periodically or intermittently through a bed or channel having banks and supports fish or other aquatic life [including] watercourses having a surface or subsurface flow that supports or has supported riparian vegetation” (14 CCR 1.72).
In addition, the term “stream” can include ephemeral streams, dry washes, watercourses with subsurface flows, canals, aqueducts, irrigation ditches, and other means of water conveyance if they support aquatic life, riparian vegetation, or stream-dependent terrestrial wildlife (CDFG 1994). “Riparian” is defined as “on, or pertaining to, the banks of a stream.” Riparian vegetation is defined as “vegetation which occurs in and/or adjacent to a stream and is dependent on, and occurs because of, the stream itself” (CDFG 1994). Removal of riparian vegetation also requires a Lake and Streambed Alteration Agreement from CDFW.
Essential Fish Habitat
The Magnuson-Stevens Fishery Conservation and Management Act of 1976 was established to conserve and manage fishery resources found off the coast, as well as anadromous species and Continental Shelf fishery resources of the United States, by exercising (A) sovereign rights for the purposes of exploring, exploiting, conserving, and managing all fish within the exclusive economic zone established by Presidential Proclamation 5030, dated March 10, 1983, and (B) exclusive fishery management authority beyond the exclusive economic zone over such anadromous species, Continental Shelf fishery resources, and fishery resources in special areas.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 35 California Endangered Species Act
CDFW is responsible for administering California Endangered Species Act (CESA, CDFG Code §§2050, et seq.), which prohibits take of species that have been listed, or are considered for listing (candidate species) as threatened or endangered species within the State of California.
CESA allows for incidental take of state listed species through issuance of an Incidental Take Permit, or through a Consistency Determination in coordination with a Biological Opinion issued by the USFWS (CDFW Code Section 2081). In contrast with federal law, the definition of “take” under CESA involves actual harm to one or more members of a listed species and does not extend to modification of habitat not involving direct take.
Special-Status Species
Special-status species include those plants and wildlife species that have been formally listed, are proposed as endangered or threatened, or are candidates for such listing under the Federal Endangered Species Act (ESA) or California Endangered Species Act (CESA). These acts afford protection to both listed and proposed species. In addition, CDFW Species of Special Concern, which are species that face extirpation in California if current population and habitat trends continue, U.S. Fish and Wildlife Service (USFWS) Birds of Conservation Concern, and CDFW special-status invertebrates are all considered special-status species.
Although CDFW Species of Special Concern generally have no special legal status, they are given special consideration under CEQA. In addition to regulations for special-status species, most birds in the United States, including non-status species, are protected by the Migratory Bird Treaty Act of 1918. Under this legislation, destroying active nests, eggs, or young is illegal. Plant species on the CNPS Rare and Endangered Plant Inventory with California Rare Plant Rank of 1 or 2 are also considered special-status plant species and must be considered under CEQA. Rank 3 and Rank 4 species are afforded little or no protection under CEQA.
Other Sensitive Biological Communities
Other sensitive biological communities not discussed above include habitats that fulfill special functions or have special values. Natural communities considered sensitive are those identified in local or regional plans, policies, regulations, or by the CDFW. CDFW ranks sensitive communities as "threatened" or "very threatened" and keeps records of their occurrences in its California Natural Diversity Database (CNDDB; CDFW 2026). Sensitive plant communities are also identified by CDFW. CNDDB vegetation alliances are ranked 1 through 5, with those alliances ranked globally (G) or statewide (S) as 1 through 3 considered sensitive. Impacts to sensitive natural communities identified in local or regional plans, policies, or regulations or those identified by the CDFW or USFWS must be considered and evaluated under CEQA (CCR Title 14, Div. 6, Chap. 3, Appendix G). Specific habitats may also be identified as sensitive in city or county general plans or ordinances.
Local Regulations
Tree Protection Ordinance
In 1973, the Town of Fairfax approved Ordinance No. 387 for trees. The purpose of the ordinance is to preserve the wide variety of local native trees and to protect the benefits they provide the citizens. Chapter 8.36.020 of the Town Code defines "altering" and "tree." A Tree Permit is required for removal or significant trimming of any tree, which has a circumference of 24 inches Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 36 or more measured at 24 inches above the ground. In effect, this is a little less than an 8-inch diameter tree trunk.
DISCUSSION OF IMPACTS
a) Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Department of Fish and Wildlife (CDFW) or United States Fish and Wildlife Service (USFWS)? Less-than-Significant Impact with Mitigation Incorporated Special-Status Plants
Due to a lack of appropriate habitat elements (such as coastal salt marsh) and the presence of residential development in the surrounding landscape, it was determined that the project site has the potential to support 11 special-status plant species. However, no special-status plants were observed in the project site during the site assessments conducted for this report. Given these assessments were conducted during the appropriate blooming seasons and no specialstatus plants were observed, it is unlikely that special-status plants are present in the project site. Thus, there would be no impact to special-status plant species.
Special-Status Wildlife
The project site contains potential habitat for steelhead and six special-status bird species.
Sensitive habitat within the project site is limited to San Anselmo Creek, which is a perennial waterway. San Anselmo Creek is potentially subject to the Corps, RWQCB, and the CDFW jurisdiction. The project site also has potential to support non-special-status nesting birds. These species and their potential for occurrence within the project site are discussed in further detail below.
Impact BIO-1: Special-Status Wildlife Species
The project would have the potential to create a substantial adverse effect on special-status fish and bird species. These impacts are discussed below and would be less than significant with mitigation incorporated.
Impact BIO-1a: Steelhead and Coho Salmon, and EFH
The project site is designated as critical habitat for both CCC steelhead and Coho salmon (O. kisutch). Coho salmon are considered extirpated from the tributaries and waters of San Francisco Bay, therefore, no mitigation is required for this species. However, steelhead are presumed present within this section of San Anselmo Creek. The project site is also listed as EFH for Coho salmon and Chinook salmon (O. tshawytscha); however, neither species occurs in the watershed.
Approximately, 0.005 acre (199 square feet) of permanent impacts and 0.086 acre (3,738 square feet) of temporary impacts to steelhead, critical habitat, and EFH. Critical habitat and EFH are considered Riparian Woodland, Perennial Stream, and Unvegetated Bank habitats within the project site. Temporary, direct impacts to the creek would occur as a result of temporary dewatering and trenching within the creek bed for modifying bent footings. As described in Section 3.0, Project Description, a dewatering plan that protects aquatic resources would be required of the Contractor and reviewed and implemented. Where needed, the flow would be Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 37 diverted around the work area by building a cofferdam upstream of the location and bypassing flowing water through a diversion pipe, keeping turbidity to a minimum. BMPs would be implemented to avoid the migration of the sediments or contaminants into the water flow areas or drainage systems. Infill walls would be constructed between each pair of existing columns at each of the bridge bents. Infill walls would result in the permanent fill of 0.002 acre (78 square feet) of Unvegetated Bank and Perennial Stream habitats.
Project construction would result in temporary impacts to steelhead; however, no permanent impacts are anticipated. The bridge work would add material to the existing structures but would not create a barrier across the channel, decrease flows, change substrate size, or channelize the stream. Riprap would be placed within the riparian woodland habitat to prevent further erosion of the banks at the storm drain outfall and would not enter the creek bed. The stream channel and banks would be restored to near pre-project conditions following the completion of bridge work, recreating the gradient which currently exists.
Restoration would use previously excavated cobble and gravel substrate to mimic the channel conditions prior to excavation including creek gradient. As such, the project would not change fish passage conditions. Temporary impacts to steelhead are anticipated during project activities. Although the project would result in a minor loss of habitat for this species, it is anticipated to be negligible and would not result in an adverse impact to steelhead or its critical habitat because fish passage conditions would remain unchanged and the project site does not contain spawning or rearing habitat. Therefore, the project may affect but is not likely to adversely affect steelhead and critical habitat.
The project would not result in any changes to existing land use; and the project site would be restored to conditions similar to those before the project. Therefore, no indirect effects would occur.
Mitigation Measure BIO-1a: Steelhead and EFH
Habitat within the project site is critical habitat for both Coho salmon and steelhead. As mentioned above, while Coho salmon are considered extirpated, steelhead are considered present. In addition to the measures identified for the Perennial Stream Biological Community; the following measures shall be implemented to avoid and minimize potential project impacts to steelhead, critical habitat for steelhead, and EFH.
• Consultation with NMFS shall be conducted to ensure project design would not result in a permanent adverse effect to steelhead or critical habitat. • Work within the channel shall be conducted during the dry season (June 1 through October 31) to avoid disrupting the adult migration cycle. Work outside of this period shall require consultation with NMFS.
• Work should be conducted in isolation from flowing water. Prior to the start of construction activities, the work area should be isolated, and flowing water should be diverted around the isolated area.
• A fish salvage plan shall be developed prior to the onset of any in-water work. The plan shall be implemented by a qualified biologist during dewatering activities in San Anselmo Creek. The fish salvage plan shall include an overview of the proposed methods for dewatering, expected location and duration of dewatering activities, and methods for conducting fish salvage during dewatering activities.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 38 • Prior to construction, the contractor shall be required to prepare an Accidental Spill Prevention and Cleanup Plan. This plan shall include required spill control absorption material, for use beneath stationary equipment, to be present on-site and available at all times.
• Silt fencing or other approved sediment trapping shall be installed down gradient of the work site to minimize off-site transport of sediments. • All stockpiling of construction materials, equipment, and supplies, including storage of chemicals, refueling and maintenance, shall occur outside the creek channel. No equipment would be washed where runoff could enter the creek. • No motorized equipment shall be left within the channel (top of bank to top of bank) overnight unless a container or similar method is securely placed beneath the equipment to catch any fluid leakage. All contained fluids shall be disposed of in a permitted manner.
• The contractor shall be required to use a drilling mud and slurry seal that is nontoxic to aquatic life if there are drilling activities related to construction of the proposed project. All drilling muds and fluid shall be contained on-site in tanks and disposed of in a permitted manner. Fluids from saw cutting and other activities shall be collected and not allowed to flow into the creek.
• The creek banks shall be restored to pre-project conditions following the completion of work.
• The creek channel shall be restored to the original grade using native cobble, gravel, and soils in appropriate ratios to mimic pre-project conditions.
Impact BIO–1b: Nesting Birds and Avian Species
The project site contains potential nesting habitat for special-status and non-special-status breeding birds. Although this habitat would not be lost as a result of the project, construction activities could result in direct impacts to active nests, and construction noise could result in indirect impacts to active nests. The project site would be restored to pre-project conditions, and as such, no permanent direct impacts to nesting birds are expected. Given that the project would not result in any changes to existing land use and that the project site would be restored to preproject conditions, no indirect effects would occur.
Mitigation Measure BIO–1b: Nesting Birds and Avian Species Although potential nesting habitat for breeding birds would not be lost as a result of the project, construction could disturb active nests. The following measures shall be implemented to avoid and minimize potential impacts to special-status, and non-special-status nesting bird species:
• If project activities begin between February 15 and August 31, pre-construction surveys shall be conducted by a qualified biologist prior to ground disturbance to determine whether active nests containing eggs, chicks, or young are present beneath the bridge and in the surrounding riparian area. Pre-construction surveys for active nests shall be conducted no more than 14 days prior to ground disturbing activities. • If active nests containing eggs, chicks, or young are not observed during preconstruction surveys, construction can proceed.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 39 • If active nests containing eggs, chicks, or young are observed, a qualified biologist shall establish an exclusion zone of 25-100 feet for passerine birds and 200-500 feet for raptors, depending on the species. Appropriate exclusion distances shall be determined by a qualified biologist based on the species present and location of the nest relative to construction activities (e.g., the nest is sufficiently shielded from construction to avoid disturbance). The exclusion zone shall be marked with high visibility fencing and monitored weekly to ensure no encroachment. Ground-disturbing activities within these zones shall be prohibited until the qualified biologist confirms that the nests are no longer active. If an active nest is found after the completion of the pre-construction surveys or after construction begins, all construction activities shall stop until a qualified biologist has evaluated the nest and determined an appropriate buffer to be placed around the nest. If avoidance of a buffer zone is not feasible, CDFW shall be contacted to coordinate an appropriate course of action.
After implementation of the above avoidance and mitigation measures, impacts to special-status species, including migratory birds, would be less than significant. b) Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations, or by the CDFW or USFWS?
Less-than-Significant Impact with Mitigation Incorporated Three natural communities of special concern are present within the project site, Riparian Woodland, Perennial Stream (comprised of “Other Waters” and Wetlands), and Unvegetated Bank. The Unvegetated Bank is not itself a sensitive natural community but is included in discussion of impacts to sensitive natural communities because it is part of the federally designated Critical Habitat for two species, CCC steelhead and Coho salmon. The “other waters” and wetlands are also considered sensitive by both federal and state agencies.
As summarized in Table 1 and Table 2, the project would temporarily impact 35 square feet (less than 0.01 acre) of Riparian Woodland, 3,287 square feet (less than 0.07 acre) of Perennial Stream (comprised of 22 square feet (less than 0.01 acre) of wetlands and 3,265 square feet of “other waters” (less than 0.07 acres), and 416 square feet (0.01 acre) of Unvegetated Bank habitats. It would permanently impact 121 square feet (less than 0.01 acre) of Riparian Woodland, 20 square feet (less than 0.01 acre) of Perennial Stream (all “other waters”, no wetland), 58 square feet (less than 0.01 acre) of Unvegetated Bank, and 805 square feet (0.02 acre) of Ruderal Disturbed/Developed lands.
Areas of temporary impacts would be revegetated following construction where appropriate. To the extent feasible, areas amid or adjacent to the rock used to stabilize the storm drain would be revegetated with appropriate native species. There is one small (<6” DBH) alder near the rock work. The alder would be avoided if possible. If it must be removed, it would be replaced onsite. No other permanent or temporary impacts to alders or willows are proposed.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 40 Table 1. Proposed Project Direct Impacts to Natural Communities of Special Concern
NATURAL COMMUNITY
OF SPECIAL CONCERN PERMANENT IMPACTS TEMPORARY IMPACTS
Riparian Woodland 0.003 acre (121 ft2) <0.001 acre (35 ft2) Perennial Stream
“Other Waters” <0.001 acre (20 ft2)/
25 linear feet
0.075 acre (3,265 ft2)/
275 linear feet
Wetlands 0.0 ft2 <0.001 acre (22 ft2)
Unvegetated Bank (included here
because it is considered part of the
federal-designated Critical Habitat for
CCC steelhead and Coho salmon.)
0.001 acre (58 ft2) 0.010 acre (416 ft2)
Total (and Total for Critical Habitat for
CCC steelhead and Coho salmon.) 0.005 acre (199 ft2
) 0.086 acre (3,738 ft2)
Table 2. Proposed Project Direct Impacts to Jurisdictional Areas by Agency
AGENCY JURISDICTION PERMANENT
IMPACTS TEMPORARY IMPACTS
CDFW (Riparian woodland, unvegetated
bank, and creek bed)
0.005 acre (199 ft2) 0.086 acre (3,738 ft2)
Corps and RWQCB (creek bed) <0.001 acre (20 ft2) 0.075 acre (3,287 ft2) NMFS (Riparian woodland, unvegetated
bank, and creek bed because of critical
habitat)
0.005 acre (199 ft2) 0.086 acre (3,738 ft2)
Impact BIO–2: Sensitive Habitat
Appendix A, Figure 3b shows the areas of the project’s impacts. The following sections present a discussion of the impacts and mitigation for each natural community of special concern.
Permanent impacts are a conversion of a natural community to structures such as bridge support or to an area of engineered slope stabilization. Temporary impacts are disturbances to existing natural communities that would be restored to the same natural community type following construction (such as dewatering).
Impact BIO-2a: Riparian Woodland
The area of Riparian Woodland impacted by the project is minor in the context of the surrounding landscape and relative abundance of this community in Marin County. Approximately
0.64 acre of Riparian Woodland is present in the project site (Appendix A, Figure 3a).
As summarized in Table 1 above, 0.003 acre of permanent impacts and <0.001 acre of temporary impacts to Riparian Woodland are unavoidable as a result of project construction. Temporary Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 41 direct impacts to Riparian Woodlands would result from tree trimming, if needed, for construction access. These areas would be revegetated following construction activities. Minor temporary indirect impacts to Riparian Woodlands would result from construction activities including increased dust deposition on adjacent vegetation. Permanent impacts would occur when the storm drain outfall is replaced and stabilized with rock.
Mitigation Measure BIO–2a: Riparian Woodland
The following avoidance and minimization measures shall be employed to avoid or minimize impacts to riparian woodland:
• Temporarily impacted areas in this habitat shall be revegetated with native, noninvasive plants suitable for the soil and site conditions. • Silt fencing or other approved sediment trapping shall be installed down gradient of the work site to minimize off-site transport of sediments. • Exclusion fencing shall be installed along the limits of clearing and grubbing to prevent encroachment into undisturbed habitats.
c) Have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means?
Less-than-Significant Impact with Mitigation Incorporated As summarized in Table 1 above, less than 0.001 acre (20 square feet, approximately 25 linear feet) of permanent impacts and 0.075 acre (3,265 square feet, approximately 275 linear feet) of temporary impacts to potentially jurisdictional “other waters” (creek bed) are proposed. Less than 0.001 acre (22 ft2) of temporary impacts and no permanent impacts to wetlands are proposed. Implementation of the following mitigation measures alongside compliance with applicable CDFW and Corps permits would reduce impacts to less-than-significant levels.
Impacts to state and federally protected wetlands would therefore be less than significant with mitigation incorporated.
Impact BIO-3: Perennial Streams and Wetlands
Temporary, direct impacts to the creek would occur as a result of temporary trenching within the creek bed for modifying bent footings and during dewatering. Cofferdams would be constructed in the creek to temporarily dewater the project area. Infill walls would be constructed between each pair of columns at each of the bridge bents. Infill walls would result in the permanent fill within the creek bed.
Temporary, indirect impacts may occur if construction-related sediment enters creeks within the project site. However, implementation of construction BMPs described in Mitigation Measure BIO-3 would ensure such impacts are avoided.
The proposed project primarily involves short-term, temporary impacts and would not disrupt connectivity in the region. The creek channel would be restored to conditions similar to preproject conditions which would allow for continued fish passage following the completion of work.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 42 Potentially significant impacts would be reduced to a less-than-significant level through implementation of Mitigation Measure BIO-3.
Mitigation Measure BIO-3: Perennial Stream and Wetlands: Creek Habitat The following measures are included to avoid and/or minimize and restore potential impacts to creek habitat resulting from the use of mechanical equipment in the creek bed. • The construction contractor shall ensure all in-stream construction work is completed during the dry season, between April 15 and October 15. Work outside of this period shall require written approval from the CDFW and RWQCB, and any additional mitigation measures prescribed shall be implemented.
• Final grading in the creek bed shall conform to the existing creek channel both downstream and upstream, and existing bed materials shall be replaced with similar sized materials.
• Regulatory approval shall be obtained for all work within potentially jurisdictional areas, including approval from the Corps, RWQCB, CDFW, and NMFS. All work within these areas shall conform to any conditions imposed by the regulating agencies. • Prior to any clearing, grubbing, pruning, or groundbreaking activity, the limits of construction shall be fenced with temporary high-visibility construction fencing to protect environmentally sensitive areas, including all riparian or wetland vegetation and prevent any equipment from unnecessarily extending the work area or entering the wetted channel. In addition, silt fencing shall be installed at the base of the construction fencing to prevent debris from entering the creek. All fencing shall be removed upon project completion.
• Prior to construction, the contractor shall be required to prepare an Accidental Spill Prevention and Cleanup Plan. This plan shall include required spill control absorbent material, for use beneath stationary equipment, to be present on-site and available at all times.
• To minimize fluid leaks during operation, refueling, and maintenance of stationary equipment spill control absorbent material shall be in place underneath this equipment at all times to capture potential leaks. All refueling and maintenance of equipment, other than stationary equipment, shall occur outside the creek’s top-ofbank. Any hazardous chemical spills shall be cleaned immediately. • All stockpiling of construction materials, equipment, and supplies, including storage of chemicals, refueling and maintenance, shall occur outside the creek channel. No equipment shall be washed where runoff could enter the creek. • No motorized equipment is to be left within the channel (top of bank to top of bank) overnight unless a container or similar method is securely placed beneath the equipment to catch any fluid leakage. All contained fluids shall be disposed of in a permitted manner.
• The contractor shall be required to use a drilling mud and slurry seal that is nontoxic to aquatic life if there are drilling activities related to construction of project. All drilling muds and fluid shall be contained on-site in tanks and disposed of in a permitted manner. Fluids from saw cutting and other activities shall be collected and not allowed to flow into the creek.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 43 • No equipment, including concrete trucks, shall be washed within the channel of the creek, or where wash water could flow into the channel. Prior to project construction, the contractor shall establish a concrete washout area for concrete trucks in a location where wash water shall not enter the creek or adjacent areas. The washout area shall follow the practices outlined in the San Francisco Bay Regional Water Quality Control Board Erosion and Sediment Control Field Manual (page 107-108, July 1999) or equivalent guidelines. Substitution of the designated concrete washout area or methods shall require prior approval of the Town of Fairfax. • All water that comes in contact with wet concrete must be pumped directly into tanks and disposed of at a permitted location.
• If work is to occur on the roadway and bridge approaches during the period October 15 to June 15, all drainage inlets within the project site shall be protected from receiving polluted storm water through the use of filters such as fabrics, gravel bags, straw wattles, or other appropriate BMPs.
• Water encountered during construction of the bridge foundations shall be managed in accordance with an approved dewatering plan.
• All workers shall ensure that food scraps, paper wrappers, food containers, cans, bottles, and other trash from the project site are deposited in covered or closed trash containers. The trash containers shall not be left open and unattended overnight. • The Town of Fairfax shall require that all disturbed areas around the bridge bents and abutments be re-graded to match the surrounding topography by October 15. Seed and certified weed-free straw shall be placed on disturbed areas in the project site (with the exception of the lower creek banks, creek bed, and areas below the OHWM).
A jute mesh type or equivalent matting shall be placed over the straw, installed per the manufacturer’s instructions. This matting shall have no plastic incorporated into it. Substitution of materials or erosion control methods shall require prior approval of the Town of Fairfax.
• After construction, the project site shall be inspected following the first heavy rain, during the middle of the rainy season and at the end of the rainy season. During each visit areas of significant erosion or erosion control device failure shall be noted and appropriate remedial actions taken.
With the implementation of these measures, it is expected that the project would not result in substantial adverse impacts to creek habitat.
d) Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites?
Less-than-Significant Impact
No migratory corridors or nursery sites are anticipated to be affected by the project. The project site does not contain spawning or rearing habitat for steelhead and critical habitat for fish passage. The bridge work would add material to the existing structures but would not create a barrier across the channel, decrease flows, change substrate size, or channelize the stream.
Riprap would be placed within the riparian woodland habitat to prevent further erosion of the banks at the storm drain outfall, and would not enter the creek bed. The stream channel and Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 44 banks would be restored to near pre-project conditions following the completion of bridge work, recreating the gradient which currently exists. Restoration would use previously excavated cobble and gravel substrate to mimic the channel conditions prior to excavation including creek gradient. As such, the project would not change fish passage conditions. Bank Swallow (Riparia riparia) has the potential to pass through the project site during migration. The proposed project primarily involves short-term, temporary construction-related impacts and would not disrupt connectivity in the region. Therefore, potential impacts to wildlife corridors or nursery sites would be less than significant.
e) Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
Less-than-Significant Impact
The Town of Fairfax Tree Protection Ordinance requires a permit for the removal or significant trimming of any tree, which has a circumference of 24 inches or more measured at 24 inches above the ground. No trees are proposed to be removed as part of the proposed project.
Temporary direct impacts to Riparian Woodlands would result from tree trimming, if needed, for construction access. These areas would be revegetated following construction activities.
Consistency with the Tree Ordinance would ensure that the proposed project would not conflict with any local policies or ordinances protecting biological resources and impacts would be less than significant.
f) Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan?
No Impact
No state, regional, or federal habitat conservation plans or Natural Community Conservation Plans have been adopted for the project site. No impact would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 45 4.2.5 Cultural Resources
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Cause a substantial adverse change in the
significance of a historical resource
pursuant to Section 15064.5?
b) Cause a substantial adverse change in the
significance of an archaeological resource
pursuant to Section 15064.5?
c) Disturb any human remains, including
those interred outside of dedicated
cemeteries?
ENVIRONMENTAL SETTING
The proposed project is located in a residential neighborhood of the Town of Fairfax in Marin County. The archaeological APE was formulated by consultation between the Town of Fairfax and Caltrans District 4 Professionally Qualified Staff and includes all areas of direct impacts proposed for the project. The vertical APE varies over the project area but includes the excavation of trenches three feet in depth in the roadbed above the creek, and five feet below the bridge structure within the creek bed Group.
Far Western Anthropological Research Inc. (Far Western) was retained to prepare the following cultural resources services for the proposed bridge project: 1) Records Search; 2) Archeological Survey Report (ASR); and 3) Extended Phase I Report. JRP Historical Consulting (JRP) was retained to prepare the following cultural resources services for the proposed bridge project: 1) Historical Resources Evaluation Report (HRER); 2) Historical Property Survey Report (HPSR); and 3) Public Participation Consultation. A brief summary of the results of these services is provided below.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 46 Public Participation
JRP Historical Consulting, LLC, (JRP) identified potential local interested parties for this project and sent notification letters on May 7, 2015. Recipients of the letter were the Fairfax Historical Society and the Marin History Museum. JRP received no responses to the letters. JRP conducted follow-up e-mails on May 22, 2015. At that time it was revealed that the Marin History Museum was being dissolved, no further contact was possible. The Fairfax Historical Society referred JRP to the Town of Fairfax and recommended any alterations to the bridge reflect the historic design.
Historical Resources Evaluation Report
The residence at 30 Creek Road is the sole historic resource within the APE that required evaluation. The Creek Road Bridge over San Anselmo Creek was previously evaluated as part of the Caltrans Historic Bridge Inventory and found not eligible for the National Register of Historic Places (NRHP). The residence evaluated in this report does not appear to meet the criteria for listing in the NRHP or the California Register of Historic Resources (CRHR) because of a lack of historic significance (JRP 2025). The residence also has been evaluated in accordance with Section 15064.5(a)(2)-(3) of the CEQA Guidelines, using the criteria outlines in Section 5024.1 of the California Public Resources Code, and does not appear to be a historical resource for the purposes of CEQA.
Historical Property Survey Report
The 1979 Report on the Architectural and Historical Significance of the Bridges Found Within the Corte Madera Creek Flood Control project Study Area by Carroll W. Pusell Jr. evaluated 12 bridges through the Corte Madera Creek watershed but did not include Creek Road Bridge (27C-0144) as, at that time, it was not yet 50 years of age.
No built-environment resources were identified in the APE in the records search.
The APE includes the bridge—Creek Road Bridge (27C-0144). The bridge was previously determined to be ineligible for the National Register of Historic Places, and it is recorded as an ineligible bridge in the Caltrans Historic Highway Bridge Inventory.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 47 Far Western conducted an archaeological survey of all visible ground surfaces in the creek bed, bank and around the bridge. No cultural materials were observed.
JRP Historical Consulting, LLC, (JRP) staff conducted a field survey of the APE and recorded the residence at 30 Creek Road, the bridge, and searched for remnants of the earlier wooden foot bridge that had been located in this vicinity. JRP staff did not identify any other buildings, structures, or objects in the APE that required recordation.
DISCUSSION OF IMPACTS
a) Cause a substantial adverse change in the significance of a historical resource pursuant to CEQA Guidelines Section 15064.5?
No Impact
No historic properties/cultural resources listed, determined, or potentially eligible for inclusion on the NRHP (36 CFR Part 800.4) and/or CRHR (California Public Resources Code Section 5024.1) were identified within or immediately adjacent to the proposed project's APE (JRP 2025). The bridge is not considered historic and has a value of 5 for Historical Significance (National Bridge Inventory, or NBI, Item No. 37), which identifies it as one of the most common historic bridge types. The bridge has been evaluated by Caltrans’ Historic Bridge Inventory and was founds ineligible for listing on the NRHP and CRHR. Therefore, the project would not cause a substantial adverse change in the significance of a historical resource. No impact would occur. b) Cause a substantial adverse change in the significance of an archaeological resource pursuant to CEQA Guidelines Section 15064.5?
Less-than-Significant Impact with Mitigation Incorporated There are no known archeological resources within the APE; however, as the project includes excavation within the creek bed, there is a potential for the project to uncover such materials during construction. While fragmentary modern refuse was minimally observed during testing and did not have any historic-era characteristics and no archaeological sites were encountered during testing, the possibility of adversely affecting any accidentally unearthed resources during construction is considered a potentially significant impact but can be mitigated to a less than significant level via implementation of Mitigation Measure CUL-1.
Mitigation Measure CUL-1 – Unknown Archaeological Resources If any archaeological deposits are encountered, the construction contractor shall immediately halt all soil-disturbing work within 25 feet of the discovery. A qualified archaeologist shall assess the significance of the find(s) and prepare a recommendation for further action. If the archaeological materials are determined to be significant, a qualified cultural resources professional shall develop an appropriate treatment plan in consultation with the Town. The plan could include avoidance and preservation measures to preserve the materials in place; scientific collection and analysis; preparation of a professional report in accordance with current professional standards; and professional museum curation of collected cultural materials and resource documentation. Soil-disturbing work within the area of the find shall not resume until a treatment plan has been approved by the Town of Fairfax.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 48 c) Disturb any human remains, including those interred outside of dedicated cemeteries? Less-than-Significant Impact with Mitigation Incorporated Human remains are not known to occur on the project site. However, the potential to uncover human remains is still present which is considered a potentially significant impact. Adherence to Mitigation Measure CUL-2 would reduce the possibility of disturbing accidentally discovered human remains to a less than significant level.
Mitigation Measure CUL-2 – Human Remains
In the event of post-review discoveries of human remains, the project shall implement the following procedures:
• The treatment of human remains and of associated or unassociated funerary objects discovered during any soil-disturbing activity within the project shall comply with applicable State laws. Pursuant to Section 7050.5 of the Health and Safety Code, and PRC Section 5097.94, in the event of the discovery of human remains during construction, there shall be no further excavation or disturbance of the site or any nearby area reasonably suspected to overlie adjacent remains. The Marin County Coroner shall be immediately notified and shall make a determination as to whether the remains are Native American.
• In the event of the coroner's determination that the human remains are Native American, notification of the NAHC, is required who shall appoint a Most Likely Descendant (MLD) (PRC Section 5097.98). The archaeological consultant, project sponsor, and MLD shall make all reasonable efforts to develop an agreement for the treatment, with appropriate dignity, of human remains and associated or unassociated funerary objects (CEQA Guidelines Section 15064.5(d)). The agreement should take into consideration the appropriate excavation, removal, recordation, analysis, custodianship, curation, and final disposition of the human remains and associated or unassociated funerary objects. California Public Resources Code allows 48 hours to reach agreement on these matters. If the MLD and the other parties do not agree on the reburial method, the project shall follow PRC Section 5097.98(b) which states that "the landowner or his or her authorized representative shall reinter the human remains and items associated with Native American burials with appropriate dignity on the property in a location not subject to further subsurface disturbance."
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 49 4.2.6 Energy
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Result in potentially significant environmental
impact due to wasteful, inefficient, or
unnecessary consumption of energy resources,
during project construction or operation?
b) Conflict with or obstruct a state or local plan
for renewable energy or energy efficiency?
DISCUSSION OF IMPACTS
a) Result in a potentially significant environmental impact due to wasteful, inefficient, or unnecessary consumption of energy resources, during project construction or operation? Less-than-Significant Impact
Bridge retrofit would require the use of energy resources to power equipment and move workers and supplies to and from the site. Machinery idling would be limited per California law and equipment would be staged on and near the project site, minimizing the use of energy resources for equipment use and transportation. Following construction, energy use would be comparable to baseline levels. Operations of the bridge would not change, and capacity would not be expanded, so energy consumption by cars using the bridge would be more or less unchanged. As there would be a temporary, minimal increase in energy use during construction and energy use would return to baseline levels during operation, the project would result in less than significant impacts related to the wasteful, inefficient, and unnecessary consumption of energy resources. b) Conflict with or obstruct a state or local plan for renewable energy or energy efficiency? No Impact
The Town of Fairfax’s Climate Action Plan contains energy efficiency goals for the Town. Although it does not provide any mandatory policies for energy efficiency or renewable energy, it provides 18 recommended actions for businesses, residents, and government entities to improve energy efficiency and the use of renewables. Most of these recommended policies are tailored towards buildings and are not applicable to the proposed project.
Similarly, there are few requirements of state-wide plans and policies such as Title 24 that apply to seismic retrofit projects. As few local and state energy renewability and efficiency programs and policies apply to the project, there would be no conflict with any such programs and policies; and no impact would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 50 4.2.7 Geology and Soils
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving:
i) Rupture of a known earthquake fault,
as delineated on the most recent
Alquist-Priolo Earthquake Fault Zoning
Map issued by the State Geologist for
the area or based on other substantial
evidence of a known fault?
ii) Strong seismic ground shaking?
iii) Seismic-related ground failure,
including liquefaction?
iv) Landslides?
b) Result in substantial soil erosion or the loss
of topsoil?
c) Be located on a geologic unit or soil that is
unstable, or that would become unstable as
a result of the project, and potentially result
in on- or off-site landslide, lateral
spreading, subsidence, liquefaction, or
collapse?
d) Be located on expansive soil, as defined in
Table 18-1-B of the Uniform Building Code,
creating substantial direct or indirect risks
to life or property?
e) Have soils incapable of adequately
supporting the use of septic tanks or
alternative wastewater disposal systems
where sewers are not available for the
disposal of wastewater?
f) Directly or indirectly destroy a unique
paleontological resource or site or unique
geologic feature?
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 51 ENVIRONMENTAL SETTING
On-Site Geologic Conditions
Soils
The soils that occur in the project site are Xerorthents-Urban land complex (0 to 9 percent slopes), which is on the western half of the site and Tocaloma-McMullin-Urban land complex (30 to 50 percent slopes), on the eastern half of the site (USDA NRCS 2015). The TocalomaMcMullin-Urban land complex is a fine-loamy, mixed, mesic Typic Haploxeroll. Its drainage class is well drained. Soil taxonomy information is not available on the Xerorthents-Urban land complex.
Seismicity
The San Francisco Bay area is one of the most seismically active areas in the country. While seismologists cannot predict earthquake events, the U.S. Geological Survey’s Working Group on California Earthquake Probabilities (2003) estimates there is a 62 percent chance of at least one magnitude 6.7 earthquake occurring in the Bay Area region between 2003 and 2032. As seen with damage in San Francisco and Oakland due to the 1989 Loma Prieta earthquake that was centered about 50 miles south, significant damage can occur at considerable distances. Higher levels of shaking and damage would be expected for earthquakes occurring at closer distances.
The faults considered capable of generating significant earthquakes in the area are generally associated with the well-defined areas of crustal movement, which trend northwesterly. Faults considered active by the State of California and located closest to the site include: San Andreas (6.9 miles, west of the site), and Hayward (13.2 miles, east of the site). The project area is not located within a State-designated Alquist-Priolo Earthquake fault rupture zone (California Geological Survey [CGS] 2019).
Liquefaction and Lateral Spreading
Soil liquefaction is a condition where saturated granular soils near the ground surface undergo a substantial loss of strength during seismic events. Loose, water-saturated soils are transformed from a solid to a liquid state during ground shaking. Liquefaction can result in significant deformations and ground rupture or sand boils. Soils most susceptible to liquefaction are loose, uniformly graded, saturated, fine-grained sands that lie close to the ground surface. Lateral spreading is a type of ground failure related to liquefaction. It consists of the horizontal displacement of flat-lying alluvial material toward an open area, such as a steep bank of a stream channel. According to the Association of Bay Area Governments (ABAG), the project area is located in a moderate liquefaction hazard zones (ABAG 2020).
Landslide
The project area is illustrated as flatland by ABAG and is not located within a debris flow source area. Therefore, the project site would not be susceptible to earthquake-induced landslides or rainfall-induced landslides (ABAG 2020).
DISCUSSION OF IMPACTS
a-i) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving: Rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault? Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 52 No Impact
The project site is not included in an earthquake fault zone designated by the Chief of the California Geological Survey pursuant to the Alquist-Priolo Act because there are no known faults in the project area. Because the project is not located near a known fault, the project will not expose people or structures to potential substantial adverse effects involving rupture of a known earthquake fault.
a-ii) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving: Strong seismic ground shaking? Less-than-Significant Impact
The Creek Road Bridge was labeled a Category 1 Bridge, meaning it would fail catastrophically under the MCE, and could potentially result in the loss of life. The Creek Road Bridge is composed of a series of articulated simple spans sitting on top of concrete bent cap beams on 2-column concrete bents. This configuration is one of the vulnerabilities of the bridge. Since the superstructure spans are not connected to the substructure, they have the potential of unseating and collapsing during large seismic events. The purpose of the project is to seismically retrofit the bridge to prevent its catastrophic failure and the loss of life. The newly retrofitted bridge would be built according to the provisions of the California Building Code, which establishes structural seismic requirements. As the bridge would be more resilient to groundshaking following construction and the building code’s seismic provisions would be complied this, impacts would be substantially mitigated by uniformly applicable development policies. a-iii) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving: Seismic-related ground failure, including liquefaction? Less-than-Significant Impact
Liquefaction associated with ground shaking is possible given ABAG’s hazard map. However, the construction phase of the proposed project is temporary and operation of the proposed project would be similar to existing conditions. In addition, design of project components would adhere to California Building Code requirements specific to the area to minimize the potential for damage from earthquake activity in the future. Impacts associated with liquefaction would be less than significant.
a-iv) Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving: Landslides?
Less-than-Significant Impact
The term landslide includes a wide range of ground movement, such as rock falls, deep failure of slopes, and shallow debris flows. Gravity acting on an over-steepened slope is the primary reason for a landslide. Slope material that becomes saturated with water may develop a debris flow or mud flow. The resulting slurry of rock and mud may pick up trees, houses, and cars, thus blocking bridges and tributaries causing flooding along its path. Any area composed of very weak or fractured materials resting on a steep slope can and will likely experience landslides.
Although the physical cause of many landslides cannot be removed, geologic investigations, good engineering practices, and effective enforcement of land-use management regulations can reduce landslide hazards. The potential for landslides or liquefaction from seismic activity is Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 53 considered low in the project site based on the geologic units and relatively flat topography. The project site is not located in an Association of Bay Area Government (ABAG) designated earthquake-induced landslide area or within an existing rainfall-induced landslide or debris flow area. Therefore, seismic-related ground failure is not anticipated at the project site and the site is not located in an area that would be subject to landslides or mudslides. Therefore, this is a less-than-significant impact.
b) Result in substantial soil erosion or the loss of topsoil? Less-than-Significant Impact with Mitigation Incorporated The project proposes to excavate sediments around bridge supports (Bents 2-4) included excavating a trench for full shoring, embedded riprap, and layers of bottom rock. Soils excavated from this work would be stored above the project site and used later for backfill of the trenches.
Mitigation Measure BIO-4 in Section 4.2.4, Biological Resources, addresses erosion and siltation impacts to the Perennial Stream (“Other Waters” and Wetlands) by listing avoidance and minimization measures. These measures include BMPs such as silt fencing, jute mesh, straw wattles, compliance with the RWQCB’s Erosion and Sediment Control Field Manual, and post construction erosion monitoring. Implementation of Mitigation Measure BIO-4 and HYDRO-1 in Section 4.2.10, Hydrology and Water Quality, would reduce potentially significant impacts related to soil erosion to a less-than-significant level.
c) Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction, or collapse?
Less-than-Significant Impact
The predominant geologic units underlying the Town of Fairfax are bedrock and alluvium. These deposits are typically those that are the most susceptible to seismic shaking, liquefaction, and differential settlement. Although these geologic units are typically susceptible to such hazards, according the ABAG Resilience Program Hazard Map the potential for liquefaction at the project site is moderate. The purpose of the proposed project is a seismic retrofit of the existing bridge structure in order to address vulnerabilities and prevent failure resulting in collapse or loss of life during the Maximum Credible Earthquake. The project site is located on flatland and would therefore have no potential for landslides.
d) Be located on expansive soil, as defined in Table 18 1 B of the Uniform Building Code, creating substantial direct or indirect risks to life or property? No Impact
The potential for geologic and soil hazards from unstable or expansive soils in the project site is considered negligible based on data from the County of Marin: Marin Map Data Viewer. Thus, there would be no direct or indirect risks to life or property due to expansive soil and no impact would occur.
e) Have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems where sewers are not available for the disposal of wastewater?
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 54 No Impact
The project does not involve construction of septic tanks or wastewater disposal systems. No impact would occur.
f) Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature?
Less-than-Significant Impact with Mitigation Incorporated While no paleontological resources were discovered during the pedestrian and XPI surveys, three prehistoric sites are present within one-quarter miles of the proposed project site. As the potential for discovery of paleontological resources is still present the following mitigation measure would reduce impacts to a less than significant level.
Mitigation Measure GEO-1: Paleontological Resources
In the event of post-review discoveries of paleontological resources the following recommendations apply:
• If any paleontological deposits or unique geological resources are encountered, all soil-disturbing work shall be halted at the location of any discovery until a qualified paleontologist or geologist evaluates the significance of the find(s) and prepares a recommendation for further action. If the materials are determined to be significant, a qualified professional shall develop an appropriate treatment plan in consultation with the Town and the Environmental Protection Agency (EPA) to mitigate the discovery. The plan could include avoidance and preservation measures to preserve the materials in place; scientific collection and analysis; preparation of a professional report in accordance with current professional standards; and, professional museum curation of collected materials and resource documentation.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 55 4.2.8 Greenhouse Gas Emissions
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Generate greenhouse gas emissions, either
directly or indirectly, that may have a
significant impact on the environment?
b) Conflict with any applicable plan, policy, or
regulation of an agency adopted for the
purpose of reducing the emissions of
greenhouse gases?
ENVIRONMENTAL SETTING
Unlike emissions of criteria and toxic air pollutants, which have local or regional impacts, emissions of greenhouse gases (GHGs) that contribute to global warming or global climate change have a broader, global impact. Global warming is a process whereby GHGs accumulating in the atmosphere contribute to an increase in the temperature of the earth’s atmosphere. The principal GHGs contributing to global warming are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated compounds. These gases allow visible and ultraviolet light from the sun to pass through the atmosphere, but they prevent heat from escaping back out into space.
Among the potential implications of global warming are rising sea levels, and adverse impacts to water supply, water quality, agriculture, forestry, and habitats. In addition, global warming may increase electricity demand for cooling, decrease the availability of hydroelectric power, and affect regional air quality and public health. Like most criteria and toxic air pollutants, much of the GHG production comes from motor vehicles. GHG emissions can be reduced to some degree by improved coordination of land use and transportation planning on the city, county, and subregional level, and other measures to reduce automobile use.
In 2010, BAAD adopted quantitative thresholds of significance for construction activities, but only identified GHG thresholds of significance for operational emissions; the Town identified no GHG thresholds for construction-related activities.
DISCUSSION OF IMPACTS
Unlike emissions of criteria and toxic air pollutants, which have local or regional impacts, emissions of greenhouse gases (GHGs) that contribute to global warming or global climate change have a broader, global impact. Global warming is a process whereby GHGs accumulating in the atmosphere contribute to an increase in the temperature of the earth’s atmosphere. The principal GHGs contributing to global warming are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated compounds. These gases allow visible and ultraviolet light from the sun to pass through the atmosphere, but they prevent heat from escaping back out into space.
Among the potential implications of global warming are rising sea levels, and adverse impacts to water supply, water quality, agriculture, forestry, and habitats. In addition, global warming may increase electricity demand for cooling, decrease the availability of hydroelectric power, and affect regional air quality and public health. Like most criteria and toxic air pollutants, much of Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 56 the GHG production comes from motor vehicles. GHG emissions can be reduced to some degree by improved coordination of land use and transportation planning on the city, county, and subregional level, and other measures to reduce automobile use.
In 2010, BAAD adopted quantitative thresholds of significance for construction activities, but only identified GHG thresholds of significance for operational emissions; the Town identified no GHG thresholds for construction-related activities.
a) Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment?
Less-than-Significant Impact
The BAAD has adopted thresholds of significance that were designed to establish the level at which GHG emissions would cause significant environmental impacts under CEQA. The thresholds are included in the 2022 CEQA Air Quality Guidelines (BAAD 2022).
The project would produce GHG emissions from temporary construction-related activities, including operation of heavy equipment, use of trucks, and worker trips to and from the project sites. The proposed project would not result in an increase in generation of GHG emissions after construction is complete. GHG emissions from project operation would be limited to vehicular trips and equipment emissions during occasional maintenance activities, which would be similar to or less than pre-project conditions.
The BAAD does not have an adopted threshold of significance for construction GHG emissions.
The BAAD’s approach to developing thresholds of significance for GHG impacts is to use a “fair share” approach to determine whether an individual project’s GHG emissions would be cumulatively considerable. If a project would contribute its “fair share” of what is needed to achieve statewide long-term GHG reduction goals, the impact of the project’s GHG emission would be less than significant. The BAAD has identified required design elements that land use projects must incorporate into project plans in order for the operational impact of their project to be considered less than significant. There are no design elements required for transportation infrastructure projects, and therefore the project must only be consistent with the local GHG reduction strategy that meets the criteria under State CEQA Guidelines Section 15183.5(b) (BAAD 2022).
The Fairfax Climate Action Plan 2030 is the relevant GHG reduction strategy which sets goals for the Town of Fairfax to achieve carbon neutrality by 2030 (Town of Fairfax 2021). The plan contains a variety of regulatory, incentive-based and voluntary strategies that are expected to reduce emissions from both existing and new development in the Town. The key strategies revolve around transportation, renewable energy and electrification, energy efficiency, waste reduction, and water conservation. The plan does not contain policies that apply to construction projects and does not set specific GHG emissions thresholds for construction projects. Therefore, the project would not conflict with the Climate Action Plan. The impact would be less than significant.
b) Conflict with any applicable plan, policy, or regulation of an agency adopted for the purpose of reducing the emissions of greenhouse gases?
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 57 No Impact
As described above in Impact a), the applicable local plan adopted for the purpose of reducing GHG emissions is the Town’s Climate Action Plan. The project would generate GHG emissions during project construction; however, the plan contains no policies related to GHG emissions from construction equipment or activities. The project would not create any new permanent source of GHG emissions or cause an increase in existing GHG emissions because the project would not expand roadway capacity. Therefore, the project would not conflict with any goals identified in the Town’s Climate Action Plan. No impact would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 58 4.2.9 Hazards and Hazardous Materials
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Create a significant hazard to the public or
the environment through the routine
transport, use, or disposal of hazardous
materials?
b) Create a significant hazard to the public or
the environment through reasonably
foreseeable upset and accident conditions
involving the release of hazardous materials
into the environment?
c) Emit hazardous emissions or handle
hazardous or acutely hazardous materials,
substances, or waste within one-quarter mile
of an existing or proposed school?
d) Be located on a site which is included on a
list of hazardous materials sites compiled
pursuant to Government Code Section
65962.5 and, as a result, would it create a
significant hazard to the public or the
environment?
e) For a project located within an airport land
use plan or, where such a plan has not been
adopted, within two miles of a public airport
or public use airport, would the project result
in a safety hazard for people residing or
working in the project area?
f) Impair implementation of or physically
interfere with an adopted emergency
response plan or emergency evacuation
plan?
g) Expose people or structures, either directly or
indirectly, to a significant risk of loss, injury
or death involving wildland fires?
ENVIRONMENTAL SETTING
A material is considered hazardous if it appears on a list of hazardous materials prepared by a federal, state, or local agency or if it has characteristics defined as hazardous by such an agency. A hazardous material is defined in Title 22 of the California Code of Regulations as follows:
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 59 A substance or combination of substances which, because of its quantity, concentration, or physical, chemical or infectious characteristics, may either (1) cause, or significantly contribute to, an increase in mortality or an increase in serious irreversible, or incapacitating reversible, illness; or (2) pose a substantial present or potential hazard to human health or environment when improperly treated, stored, transported or disposed of or otherwise managed. (California Code of Regulations, Title 22, Section 66261.10) Chemical and physical properties cause a substance to be considered hazardous. Such properties include toxicity, ignitability, corrosivity, and reactivity (as defined in California Code of Regulations, Title 22, Sections 66261.20-66261.24). The release of hazardous materials into the environment could potentially contaminate soils, surface water, and groundwater supplies. Under Government Code Section 65962.5, the California Department of Toxic Substances Control (DTSC) maintains a list of hazardous substance sites. This list, referred to as the “Cortese List,” includes CALSITE hazardous material sites, sites with leaking underground storage tanks, and landfills with evidence of groundwater contamination.
DISCUSSION OF IMPACTS
a) Create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials?
Less-than-Significant Impact with Mitigation Incorporated Small amounts of hazardous materials would be used during construction activities for equipment maintenance (e.g., fuel and solvents). Use of hazardous materials would be limited to the construction phase and would comply with applicable local, state, and federal standards associated with the handling and storage of hazardous materials. Hazardous materials would not be stored or used, such as for equipment maintenance, where they could affect nearby residences. Standard construction measures would be implemented to contain any accidental spills of oil and other hazardous materials, and the contractor would be required to ensure that adequate materials are on hand to clean up any accidental spill that may occur. Spills would be cleaned up immediately, and all wastes and used spill control materials would be properly disposed of at approved disposal facilities. With implementation of these standard measures and Mitigation Measures HYDRO-1 and HYDRO-2 in Section 4.2.10, Hydrology and Water Quality, impacts associated with the use or accidental spill of hazardous materials would be less than significant.
b) Create a significant hazard to the public or the environment through reasonably foreseeable upset and accident conditions involving the release of hazardous materials into the environment?
Less-than-Significant Impact with Mitigation Incorporated The repairs to the existing bridge would include the use of hazardous materials during the construction phase of the project such as fuels for construction vehicles. The handling and storage of these materials would be subject to all applicable local, state, and federal regulations.
No upset or accident conditions can be reasonably expected to occur under these circumstances.
Implementation of Mitigation Measure BIO-4 includes minimization measures for impacts to Perennial Streams (“Other Waters” and Wetlands) that includes the preparation of an Accidental Spill Prevention and Cleanup Plan. As the proposed project would restore the bridge to its existing functions, the operation of the bridge would not result in the generation or use of Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 60 hazardous materials. Therefore, potential impacts from accident conditions would be less than significant.
c) Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school? No Impact
Existing or proposed schools are not located within ¼ mile of the proposed project site. The nearest school, Sir Francis Drake High School, is located approximately one mile east of the project site. Additionally, operation and maintenance of the project would not emit hazardous emissions or utilize hazardous substances. Therefore, the project would have no impact with respect to emitting hazardous emissions or handling hazardous or acutely hazardous materials, substances, or waste within one-quarter mile of an existing or proposed school. d) Be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section 65962.5 and, as a result, would it create a significant hazard to the public or the environment?
No Impact
The proposed project site is not included on the list of hazardous materials sites complied pursuant to Government Code Section 65962.5 (DTSC 2025). No impact would occur. e) For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project result in a safety hazard for people residing or working in the project area? No Impact
The proposed project is not located within an airport land use plan, nor is it within two miles of a public airport or public use airport. Therefore, the project would have no impact regarding a safety hazard for people residing or working in the project area. f) Impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan?
Less-than-Significant Impact with Mitigation Incorporated During construction the Creek Road Bridge would be closed and detours would be established to and away from the bridge via Creek Road and Porteous Avenue in the direction away from the bridge towards Bolinas Road. Mitigation Measure TRANS-1 in Section 4.2.17, Transportation, would address lane closures and traffic control during construction and mitigate impacts to emergency access to less-than-significant levels. Thus, impacts would be less than significant with mitigation incorporated.
g) Expose people or structures, either directly or indirectly, to a significant risk of loss, injury or death involving wildland fires?
Less-than-Significant Impact
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 61 As further described in Section 4.2.20, Wildfire, the project site is in a High Fire Hazard Severity Zone in the local responsibility area for wildfire protection. Fire protection services in the area are provided by the Ross Valley Fire Department, with the nearest station located one mile from the project site. During construction, the use of construction equipment at the site could slightly increase the risk of unwanted combustion; however, compliance with standard construction site best management practices would ensure that any such combustion is immediately extinguished.
In addition, the Ross Valley Fire Department is located one mile from the site, and would be contacted if any accidental combustion of vegetation or materials occurs. The long-term operation of the project would not increase the risk of wildfire because no new permanent sources of combustion would be created by the project. The risk of wildfire during project operation would remain similar to the existing conditions. Therefore, the project would not expose people or structures to significant risk of loss, injury, or death involving wildland fires.
The impact would be less than significant.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 62 4.2.10 Hydrology and Water Quality
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Violate any water quality standards or waste
discharge requirements or otherwise
substantially degrade surface or ground
water quality?
b) Substantially decrease groundwater supplies
or interfere substantially with groundwater
recharge such that the project may impede
sustainable groundwater management of the
basin?
c) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river or through the addition of impervious surfaces, in a manner which would:
i) result in substantial erosion or siltation onor off-site; ii) substantially increase the rate or amount of
surface runoff in a manner which would
result in flooding on- or off-site;
iii) create or contribute runoff water that would
exceed the capacity of existing or planned
storm water drainage systems or provide
substantial additional sources of polluted
runoff; or
iv) impede or redirect flood flows?
d) In flood hazard, tsunami, or seiche zones, risk
release of pollutants due to project
inundation?
e) Conflict with or obstruct implementation of a
water quality control plan or sustainable
groundwater management plan?
ENVIRONMENTAL SETTING
The 28-square mile Corte Madera watershed extends from Mt. Tamalpais and White’s Hill through the communities of Fairfax, Sleepy Hollow, San Anselmo, Ross, Kentfield, Greenbrae, Larkspur, and Corte Madera to San Francisco Bay. The watershed includes 44 miles of stream channels. Ross Creek drains the northern slope of Mt. Tamalpais; San Anselmo Creek and its tributaries drain the northwestern portion of the watershed. The two channels join to form Corte Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 63 Madera Creek, which continues through more than a mile of concrete-lined channel past the confluences of Larkspur and Tamalpais Creeks and into the salt marsh at the mouth.
Protection of water quality in California is primarily the responsibility of the State Water Quality Control Board (SWQCB), and, on a regional basis, the nine California Regional Water Quality Control Boards. Water quality within the project sites is primarily under the jurisdiction of the RWQCB, San Francisco Bay Region (Region 2). The Town of Fairfax is responsible for overseeing the requirements of its water quality codes and ordinances.
The principal natural hydrological sources for the project site are creek flows, direct precipitation and surface run-off from adjacent lands. San Anselmo Creek flows though the project site towards the north/northeast. Just north of the project site, Deer Creek joins San Anselmo Creek.
Roughly one quarter of a mile to the north, it joins Fairfax Creek and turns east, eventually flowing into Corte Madera Creek, then San Francisco Bay, and the Pacific Ocean. In wet years, the creek at this location is perennial. At the time of the fieldwork, in a drought year, the flows were low.
According to the Federal Emergency Management Agency (FEMA) Federal Insurance Rate Maps (FIRM), the project site is located in flood zone AO. Zone AO is defined as an area within the 100-year flood zone where the average flood depth is one to three feet.
According to ABAG’s Resilience Program Hazard Maps, the project site is not subject to seiches and is not within a Tsunami Inundation Area.
DISCUSSION OF IMPACTS
a) Violate any water quality standards or waste discharge requirements or otherwise substantially degrade surface or ground water quality?
Less-than-Significant Impact with Mitigation Incorporated The proposed project would require the use of hazardous materials such as vehicle fuels during the construction phase of the project. The proposed project would be required to obtain a Section 404 nationwide permit from the U.S. Army Corps of Engineers, a Section 1602 permit from CDFW, and a Section 401 Certification from the RWQCB. Mandatory compliance with all measures listed in each permit would be required for project approval. Construction activities would be required to comply with the NPDES general permit for construction activities, pursuant to which BMPs would be implemented to control stormwater during construction. As part of the permit application process, projects would require a stormwater pollution prevention plan (SWPPP), which would include a list of BMPs to be implemented on the site both during and after construction to minimize erosion and sedimentation.
The primary risk to water quality and resources would result from construction-related sediment and other pollutants entering the during a rain event. Implementation of Mitigation Measures HYDRO-1 and HYDRO-2 would reduce potential impacts related to erosion and siltation to lessthan-significant levels.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 64 Mitigation Measure HYDRO-1: NPDES Permit
The contractor shall prepare a SWPPP in accordance with the NPDES General Construction Permit, pursuant to the CWA. Best Management Practices shall be identified in the SWPPP to reduce or eliminate pollutants from the construction site entering storm water discharges.
Implementation of BMPs shall control erosion and to ensure that dirt, construction materials, pollutants, or other human-associated materials are not discharged from the project area into surface waters or into areas that would eventually drain to storm drain systems. BMPs required by the SWPPP may include but are not limited to silt fencing, erosion control blankets, and street sweeping.
Mitigation Measure HYDRO–2: Water Quality Standards
The Town of Fairfax shall require the construction contractor to submit an equipment staging plan and proposed staging locations no later than 30 days prior to the start of construction. The specifications shall include at minimum, the following requirements:
• The staging area shall be located on an existing asphalt or concrete surface area. No staging shall be permitted on undeveloped lots. The Contractor shall notify the Town whether or not a suitable area is available.
• The staging area shall be included in the Contractor’s Water Quality Protection Plan. • The staging area shall not be located in an environmentally or culturally sensitive area and /or impact water resources (rivers, streams, bays, inlet, lakes, drainage sloughs).
• The staging area shall not be located in a regulatory floodway within the base floodplain (100-year).
• The staging area shall be inspected weekly by the project environmental monitor to ensure compliance with the Water Quality Protection Plan, and any violations will result in immediate suspension of the work until rectified. b) Substantially decrease groundwater supplies or interfere substantially with groundwater recharge such that the project may impede sustainable groundwater management of the basin?
No Impact
The project would not require use of groundwater supplies or affect groundwater recharge in the area. As such, the project would not impede sustainable groundwater management of the basin and no impact would occur.
c) Substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river or through the addition of impervious surfaces, in a manner which would:
i) result in substantial erosion or siltation on- or off-site; Less-than-Significant Impact with Mitigation Incorporated The proposed repairs to the Creek Road Bridge include excavation within the creek bed, which has the potential to result in temporary erosion and siltation impacts. Implementation of Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 65 Mitigation Measures BIO-4, HYDRO-1, and HYDRO-2 would assure the use of BMPs related to erosion and siltation. Once construction is finished, vegetation disturbed by or removed for construction would be replaced so that substantial erosion or siltation would not occur. Once vegetation is established, the conditions related to erosion would be similar to existing conditions. Impacts would therefore be less than significant with mitigation incorporated. ii) substantially increase the rate or amount of surface runoff in a manner which would result in flooding on- or off-site;
Less-than-Significant Impact
The proposed project would not create or contribute additional runoff compared to existing conditions. The project would retrofit the existing bridge and would not add additional impervious surfaces that would contribute to runoff. Runoff from the project site would be similar to existing conditions and no additional capacity would be needed for the stormwater drainage systems. Since the proposed project would not contribute substantial runoff, impacts would be less than significant.
iii) create or contribute runoff water that would exceed the capacity of existing or planned storm water drainage systems or provide substantial additional sources of polluted runoff; or
Less-than-Significant Impact
The proposed project would not substantially alter the existing drainage pattern of the area. The bridge has a more than adequate waterway opening for the design floods and would not increase the width of the deck thereby increasing the amount of impervious cover present at the project site. The construction work may reduce the current bridge opening slightly but would not result in measurable water surface elevation rise up- or downstream of the bridge. A perennial creek flow is generally present during wet years but The proposed project would not contribute substantial erosion or siltation or increase the rate or amount of surface runoff in a manner which would result in flooding on- or off-site. The abandonment of the existing 12” storm water drainage pipe and the establishment and redirection of a new 12” storm water drainage pipe would ensure that the drainage capacity would remain the same as existing conditions. Since the proposed project would not contribute substantial runoff, this pipeline replacement would adequately serve the needs of the project site and impacts would be less than significant. iv) impede or redirect flood flows?
Less-than-Significant Impact
The project site is susceptible to occasional flooding. This bridge has a more than adequate waterway opening for the design floods. The required construction work may reduce the current bridge opening slightly but would not result in measurable water surface elevation increases either upstream or downstream of the bridge. The retrofitted bridge has been designed to provide adequate clearance during flooding events. Hydrological modeling prepared in support of the design process determined that there would be no appreciable change in upstream or downstream flooding due to the project. The project would not change any flood flows and flooding conditions during and after project implementation would be similar to existing conditions. Thus, the project would not impede or redirect flood flows, and impacts would be less than significant.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 66 d) In flood hazard, tsunami, or seiche zones, risk release of pollutants due to project inundation?
Less-than-Significant Impact with Mitigation Incorporated Seiche and tsunami occur near large open water bodies such as lakes and oceans. Since the project site is not located near such a water body and is sufficiently upstream from the ocean and the nearest lakes, it is not susceptible to seiche or tsunami.
Flooding is possible within the project site, and should flooding occur, pollutant release due to project inundation is possible. As described in Section 3.0, Project Description, a dewatering plan that protects aquatic resources would be required of the Contractor and reviewed and implemented. Where needed, the flow would be diverted around the work area by building a cofferdam upstream of the location and bypassing flowing water through a diversion pipe, keeping turbidity to a minimum. BMPs would be implemented to avoid the migration of the sediments or contaminants into the water flow areas or drainage systems. This would ensure that perennial flows would be diverted outside of the work area and would not be impacted by sediment or pollutants generated by project construction activities. In addition, Mitigation Measure HYDRO-2 would be implemented, which would ensure that stormwater runoff from the project site would not carry excessive pollutants and sediments into nearby waterways. With implementation of Mitigation Measure HYDRO-2, which requires preparation of a construction staging plan, this possibility would be negligible, and impacts would be reduced to less than significant levels. Impacts would therefore be less than significant with mitigation incorporated. e) Conflict with or obstruct implementation of a water quality control plan or sustainable groundwater management plan?
Less-than-Significant Impact with Mitigation Incorporated The operational project would not obstruct a water quality control plan or sustainable groundwater management plan, as bridge operations would be unchanged. During construction, equipment would be used that could impair water quality should fuels and lubricants enter waterways during flooding or spill events. This possibility is reduced to a less than significant level with implementation of Mitigation Measures BIO-4 and HYDRO-2. The project would be required to comply with BMPs contained in regulatory permits which would ensure that project work would not change the overall water quality of nearby water bodies in the long-term. Thus, impacts to water quality control plans and sustainable groundwater management plans would be less than significant with mitigation incorporated.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 67 4.2.11 Land Use and Planning
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Physically divide an established community?
b) Cause a significant environmental impact
due to a conflict with any land use plan,
policy, or regulation adopted for the purpose
of avoiding or mitigating an environmental
effect?
ENVIRONMENTAL SETTING
The Town of Fairfax General Plan provides policies and implementation strategies for management of the resources and land uses in the Town, and the Town Codes provide restrictions and requirements to protect resources and comply with local, state, and federal laws.
No habitat conservation plans have been adopted for the area.
Town of Fairfax General Plan
The proposed project is subject to the following General Plan policies:
Land Use Element
Policy LU-4.1.2: New and renewed development shall comply with all federal, state, and local regulations pertaining to development in flood zones.
Policy LU-4.1.3: New and renewed development shall comply with all regulations encompassed in the California and Uniform Building Codes intended to reduce potential damage and threats to the public’s health, safety, and welfare in the event of an earthquake.
Policy LU-7.2.2: To the extent feasible natural features including the existing grade, mature trees, and vegetation shall be preserved for new and renewed development.
Circulation Element
Policy C-2.2: Maintain the street, sidewalk and pathway network through a regular maintenance program.
Conservation Element
Policy Con-2.1.2: All planning decisions shall require application of existing air quality guidelines and best practices to minimize air quality impact.
Policy Con-2.1.3: Improve air quality by encouraging green building techniques for all new and remodel construction within the Town of Fairfax.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 68 Policy Con-3.1.1: Maintain floodwater capacity and promote creek restoration.
Policy Con-3.1.2: The Town of Fairfax shall protect and restore riparian habitat and ensure natural channel process in the San Anselmo Creek and Fairfax Creek watersheds.
Policy Con-5.2.1: Maintain and restore native vegetation where appropriate for habitat value, aesthetics, reference habitat, and riparian cover.
Policy Con-6.1.2: Protect special-status species and resident and migrant wildlife, and their habitats, within the Fairfax Planning Area (also see Goal CON-3 and Policy CON5.2.1).
Policy Con-8.2.1: Protect, maintain, rehabilitate, and enhance historical and cultural resources within the Fairfax Planning Area.
Policy Con-8.2.3: Ensure that development respects and complements the patterns, character, and scale of the Town’s traditional communities and natural landscape.
Health and Safety
Policy S-1.1.3: The Town shall identify, evaluate, and encourage the seismic retrofit of public and private buildings that pose a risk of death or injury in a geohazard event.
Policy S-3.1.3: Maximize access and egress for emergency response vehicles. Also see Conservation Element, Goal C-4.
Noise Element
Policy N-1.1.1: All new development must include an analysis of potential noise impacts.
Safety Element
Policy S-1.1.2: Geotechnical data will be easily available to the public and interested parties.
Policy S-1.1.3: The Town shall identify, evaluate, and encourage the seismic retrofit of public and private buildings that pose a risk of death or injury in a geohazard event.
DISCUSSION OF IMPACTS
a) Physically divide an established community?
No Impact
The proposed project involves the seismic retrofit of an existing bridge within the Town of Fairfax. Upon completion of construction the project site would remain the same as existing conditions. Therefore, the proposed project would not divide a community and no impact would occur.
b) Cause a significant environmental impact due to a conflict with any land use plan, policy, or regulation adopted for the purpose of avoiding or mitigating an environmental effect?
Less-than-Significant Impact
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 69 The proposed project is subject to several local policies, plans, and regulations, such as the Town of Fairfax’s General Plan and Zoning Ordinance. The proposed project is seismic retrofit of existing bridge that would improve safety and reduce the potential for hazards, as specifically called for in the Safety Element of the Town’s General Plan. The project would comply with applicable policies and ordinances of the Town of Corte Madera governing construction, noise, lighting, solid waste, and other relevant areas. Therefore, these actions would not conflict with the Town of Fairfax General Plan or other plans or policies adopted for the purpose of avoiding or mitigating an environmental effect, and less than significant impacts would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 70 4.2.12 Mineral Resources
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Result in the loss of availability of a known
mineral resource that would be of value to
the region and the residents of the state?
b) Result in the loss of availability of a locally
important mineral resource recovery site
delineated on a local general plan, specific
plan, or other land use plan?
ENVIRONMENTAL SETTING
The CDOC has mapped three mines within Marin County including the Nicasio Rock Quarry in Nicasio, the Redwood/Silveira Quarry north of Novato, and Dutra Minerals in San Rafael (CDOC 2016). The proposed project is located within an urbanized area of the Town of Fairfax and is not located near any of these mines. There are no known mineral resources within the vicinity of the project site.
DISCUSSION OF IMPACTS
a) Result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the state?
No Impact
The project site is not located within the vicinity of either of the three mines within Marin County and no other known mineral resources areas are near the project site. Furthermore, the development of the proposed project would not preclude future excavation of oil or minerals should such resources be found. Therefore, the project would not result in the loss of availability of a mineral resource that would be of value to the region and the residents of the state. b) Result in the loss of availability of a locally important mineral resource recovery site delineated on a local general plan, specific plan, or other land use plan? No Impact
The project site is not in or adjacent to any important mineral resource areas. There are no known mineral resources on the project sites as delineated in the Town of Fairfax General Plan 2010-2030. Therefore, the proposed project would have no impact.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 71 4.2.13 Noise
Would the project result in:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Generation of a substantial temporary or
permanent increase in ambient noise levels
in the vicinity of the project in excess of
standards established in the local general
plan or noise ordinance, or applicable
standards of other agencies?
b) Generation of excessive groundborne
vibration or groundborne noise levels?
c) For a project located within the vicinity of a
private airstrip or an airport land use plan
or, where such a plan has not been adopted,
within two miles of a public airport or public
use airport, would the project expose people
residing or working in the project area to
excessive noise levels?
ENVIRONMENTAL SETTING
Illingworth and Rodkin (I&R) were retained to conduct a Construction Noise and Vibration Assessment for the Creek Road Bridge (I&R 2015, Appendix C).
Noise may be defined as unwanted sound. Noise is usually objectionable because it is disturbing or annoying. The objectionable nature of sound could be caused by its pitch or its loudness. Pitch is the height or depth of a tone or sound, depending on the relative rapidity (frequency) of the vibrations by which it is produced. Higher pitched signals sound louder to humans than sounds with a lower pitch. Loudness is intensity of sound waves combined with the reception characteristics of the ear. Intensity may be compared with the height of an ocean wave in that it is a measure of the amplitude of the sound wave.
In addition to the concepts of pitch and loudness, there are several noise measurement scales, which are used to describe noise in a particular location. A decibel (dB) is a unit of measurement which indicates the relative amplitude of a sound. The zero on the decibel scale is based on the lowest sound level that the healthy, unimpaired human ear can detect. Sound levels in decibels are calculated on a logarithmic basis. An increase of 10 decibels represents a ten-fold increase in acoustic energy, while 20 decibels is 100 times more intense, 30 decibels is 1,000 times more intense, etc. There is a relationship between the subjective noisiness or loudness of a sound and its intensity. Each 10 decibel increase in sound level is perceived as approximately a doubling of loudness over a fairly wide range of intensities.
There are several methods of characterizing sound. The most common in California is the Aweighted sound level (dBA). This scale gives greater weight to the frequencies of sound to which Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 72 the human ear is most sensitive. Representative outdoor and indoor noise levels in units of dBA are shown in Table 3. Because sound levels can vary markedly over a short period of time, a method for describing either the average character of the sound or the statistical behavior of the variations must be utilized. Most commonly, environmental sounds are described in terms of an average level that has the same acoustical energy as the summation of all the time-varying events. This energy-equivalent sound/noise descriptor is called Leq. The most common averaging period is hourly, but Leq can describe any series of noise events of arbitrary duration.
The scientific instrument used to measure noise is the sound level meter. Sound level meters can accurately measure environmental noise levels to within about plus or minus 1 dBA. Various computer models are used to predict environmental noise levels from sources, such as roadways and airports. The accuracy of the predicted models depends upon the distance the receptor is from the noise source. Close to the noise source, the models are accurate to within about plus or minus 1 to 2 dBA.
Since the sensitivity to noise increases during the evening and at night -- because excessive noise interferes with the ability to sleep -- 24-hour descriptors have been developed that incorporate artificial noise penalties added to quiet-time noise events. The Community Noise Equivalent Level (CNEL) is a measure of the cumulative noise exposure in a community, with a 5 dB penalty added to evening (7:00 p.m. - 10:00 p.m.) and a 10 dB addition to nocturnal (10:00 p.m. - 7:00 a.m.) noise levels. The Day/Night Average Sound Level (Ldn) is essentially the same as CNEL, with the exception that the evening time period is dropped and all occurrences during this three-hour period are grouped into the daytime period.
Ground vibration consists of rapidly fluctuating motions or waves with an average motion of zero. Several different methods are typically used to quantify vibration amplitude. One method is the Peak Particle Velocity (PPV). The PPV is defined as the maximum instantaneous positive or negative peak of the vibration wave. In this report, a PPV descriptor with units of mm/sec or in/sec is used to evaluate construction generated vibration for building damage and human complaints. Table 4 displays the reactions of people and the effects on buildings that continuous vibration levels produce.
The annoyance levels shown in Table 4 should be interpreted with care since vibration may be found to be annoying at much lower levels than those shown, depending on the level of activity or the sensitivity of the individual. To sensitive individuals, vibrations approaching the threshold of perception can be annoying. Low-level vibrations frequently cause irritating secondary vibration, such as a slight rattling of windows, doors, or stacked dishes. The rattling sound can give rise to exaggerated vibration complaints, even though there is very little risk of actual structural damage.
Construction activities can cause vibration that varies in intensity depending on several factors.
The use of pile driving and vibratory compaction equipment typically generates the highest construction related ground-borne vibration levels. Because of the impulsive nature of such activities, the use of the PPV descriptor has been routinely used to measure and assess groundborne vibration and almost exclusively to assess the potential of vibration to induce structural damage and the degree of annoyance for humans.
The two primary concerns with construction-induced vibration, the potential to damage a structure and the potential to interfere with the enjoyment of life, are evaluated against different Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 73 vibration limits. Studies have shown that the threshold of perception for average persons is in the range of 0.008 to 0.012 in/sec PPV. Human perception to vibration varies with the individual and is a function of physical setting and the type of vibration. Persons exposed to elevated ambient vibration levels, such as people in an urban environment, may tolerate a higher vibration level.
Structural damage can be classified as cosmetic only, such as minor cracking of building elements, or may threaten the integrity of the building. Safe vibration limits that can be applied to assess the potential for damaging a structure vary by researcher and there is no general consensus as to what amount of vibration may pose a threat for structural damage to the building. Construction-induced vibration that can be detrimental to the building is very rare and has only been observed in instances where the structure is at a high state of disrepair and the construction activity occurs immediately adjacent to the structure.
Table 3. Typical Noise Levels in the Environment
COMMON OUTDOOR
ACTIVITIES
NOISE
LEVEL (DBA) COMMON INDOOR ACTIVITIES
110 Rock band
Jet fly-over at 1,000 feet
100
Gas lawn mower at 3 feet
90 Diesel truck at 50 feet at 50
mph Food blender at 3 feet
80 Garbage disposal at 3 feet
Noisy urban area, daytime
Gas lawn mower, 100 feet 70 Vacuum cleaner at 10 feet
Commercial area Normal speech at 3 feet
Heavy traffic at 300 feet 60
Large business office
Quiet urban daytime 50 Dishwasher in next room
Quiet urban nighttime 40 Theater, large conference room Quiet suburban nighttime
30 Library
Quiet rural nighttime Bedroom at night, concert hall
(background)
20 Broadcast/recording studio
10 0
Source: Technical Noise Supplement (TeNS), Caltrans, September 2013.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 74 Table 4. Reactions of People and Damage to Buildings from Continuous or Frequent Intermittent Vibration Levels
VELOCITY, PPV
(IN/SEC) HUMAN REACTION EFFECT ON BUILDINGS
0.01 Barely perceptible No effect
0.01 Distinctly perceptible
Vibration unlikely to cause damage of any
type to any structure
0.08 Distinctly perceptible
to strongly perceptible
Recommended upper level of the vibration to
which ruins and ancient monuments should
be subjected
0.1 Strongly perceptible
Virtually no risk of damage to normal
buildings
0.3 Strongly perceptible to
severe
Threshold at which there is a risk of damage
to older residential dwellings such as
plastered walls or ceilings
0.5 Severe - Vibrations
considered unpleasant
Threshold at which there is a risk of damage
to newer residential structures
Source: Transportation and Construction Vibration Guidance Manual, Caltrans, September 2013.
Existing Noise Environment
The existing Creek Road Bridge is located within a residential development with several singlefamily residences located in the vicinity of the proposed project site, as shown in. Each of these noise-sensitive land uses have the potential to be adversely affected by noise and vibration attributable to project construction activities. The main sources of noise at the project site include vehicular traffic along local roadways and the occasional planes that may fly overhead.
No airports are located in the vicinity; thus, this noise source is intermittent. Noise measurements were not taken at the project site. However, a noise contour plot in the Town’s General Plan shows that the existing noise environment in the vicinity of the project site would typically be characterized by ambient noise levels less than 60 dBA Ldn.
REGULATORY BACKGROUND
The proposed project would be subject to noise-related regulations, plans, and policies established within documents prepared by the Town of Fairfax. Applicable planning documents include the Town’s General Plan and Municipal Code.
Town of Fairfax General Plan
The Town of Fairfax’s General Plan Noise Element establishes goals, policies, and programs for noise and vibration sources. Applicable goals, policies, and implementation measures presented in the General Plan are as follows:
Goal N-3: Maintain the current quality of the acoustical environment.
Objective N-3.1: Establish a noise abatement program that preserves the existing acoustical character of the Town.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 75 • Policy N-3.1.4: Implement appropriate standard controls (e.g., some or all of Standard Controls a-h above) for all construction projects.
• Program N-3.1.4.1: Develop a guidance manual to provide information to public regarding construction noise control.
• Policy N-3.1.5: Consider CEQA review for construction projects lasting more than 18 months, and submittal of detailed construction noise management plans. • Program N-3.1.5.1: Develop a guidance manual to provide information to public regarding construction noise control.
Town of Fairfax Municipal Code
The Town’s Municipal Code provides provisions for noise control in Chapter 8.20. The portions of the Municipal Code that are relevant for this project are as follows:
Chapter 8.20.010 Policy Declaration; Nuisance Declared.
A. In order to control unnecessary, excessive and annoying noise in the town, it is declared to be the policy of the town to prohibit the noise generated from or by all sources as specified in this chapter. It is the policy of the town to maintain quiet in those areas which exhibit low noise levels and to implement programs aimed at reducing noise in those areas within the town where noise levels are above acceptable values.
B. It is determined that certain noise levels are detrimental to the public health, welfare and safety, and are contrary to public interest. Therefore, the town does ordain and declare that creating, maintaining, causing or allowing to be created, caused or maintained, any noise in a manner prohibited by or not in conformity with the provisions of this chapter, is a public nuisance. (Prior Code, § 8.16.010) (Ord. 481, passed - -1981) Chapter 8.20.030 Compliance by Town Departments.
A. All departments of the town shall carry out their activities in accordance with the provisions of this chapter.
B. Each department whose duty it is to review and approve new projects, or changes to existing projects, which result or may result in the emission of noise shall make the finding that the project complies with the provisions of this chapter prior to project approval. (Prior Code, § 8.16.030) (Ord. 481, passed - -1981) Chapter 8.20.050 Exterior Noise Limits.
A. Maximum permissible sound levels by receiving land use. 1) The noise standards for the various noise zones as presented in the following table shall, unless otherwise specifically indicated, apply to all such property within a designated zone.
2) No person shall operate or cause to be operated any source of sound at any location within the incorporated town, or allow the creation of any noise on property owned, leased, occupied or otherwise controlled by the person, which causes the noise level when measured at the complainant’s property line to Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 76 exceed the limits in the table below for more than seven and one-half minutes in a 15- minute period. Those seven and one-half minutes need not be continuous. 3) If the measured ambient level differs from that permissible, the allowable noise exposure standard shall be adjusted in five-decibel increments in each category as appropriate to encompass or reflect the ambient noise level. 4) If the measurement location is on a boundary between two different zones, the noise level limit applicable to the lower noise zone shall apply.
B. Correction for character of sound.
1) In the event the alleged offensive noise, as judged by the Chief of Police or his or her designated representative, contains a steady, audible tone such as a whine, screech or hum, or is a repetitive noise such as hammering or riveting, or contains music or speech, the standard limits set forth in Table 5 shall be reduced by five decibels.
2) These zones are illustrated on Exhibit A, “Noise Zones, Town of Fairfax,” attached to the ordinance codified in this chapter. Areas that are not covered on the map are included in Zone A. (Prior Code, § 8.16.050) (Ord. 481, passed - - 1981; Am.
Ord. 529, passed - -1984)
Table 5. Exterior Noise Limits
Chapter 8.20.060 Prohibited Acts.
C. Construction/demolition domestic power tools.
1) The operation of any tools or equipment used in construction or demolition work between weekday hours of 8:00 p.m. and 8:00 a.m. or on weekends or holidays between the hours of 8:00 p.m. and 9:00 a.m., such that the sound therefrom creates a noise disturbance across a residential or commercial real property line, is prohibited.
2) Operating or permitting the operation of any mechanically powered saw, sander, drill, grinder, lawn or garden tool or similar tool between 8:00 p.m. and 8:00 a.m. (LEVELS ARE NOT BE EXCEEDED MORE THAN 7.5 MINUTES IN ANY 15-MINUTE
PERIOD)
NOISE ZONE TIME PERIOD NOISE LEVEL
(DBA)
A (Residential) Night 10:00 p.m. - 7:00 a.m. 40
Day 7:00 a.m. - 10:00 p.m. 50
B (Multiple
Dwelling,
Residential)
Night 10:00 p.m. - 7:00 a.m. 50
Day 7:00 a.m. - 10:00 p.m. 55
C (Commercial) Night 10:00 p.m. - 7:00 a.m. 55
Day 7:00 a.m. - 10:00 p.m. 60
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 77 or on weekends or holidays between the hours of 8:00 p.m. and 9:00 a.m., so as to create a noise disturbance across a residential or commercial real property line, is prohibited.
D. Machinery. Any motor, machinery or pump, such as swimming pool equipment and the like, shall be sufficiently enclosed or muffled and maintained so as not to create a noise or disturbance.
Chapter 8.20.070 Exemptions.
D. The operation of any tools or equipment used in construction, drilling, repair, alteration or demolition work, mechanically powered saw, sander, drill, grinder, lawn or garden tool, leaf blower, or similar tool between 8:00 a.m. and 8:00 p.m. on weekdays and 9:00 a.m. and 8:00 p.m. on weekends are exempt. (Prior Code, § 8.16.070) (Ord. 481, passed - - 1981; Am. Ord. 731, passed 2-6-2008)
DISCUSSION OF IMPACTS
a) Generation of a substantial temporary or permanent increase in ambient noise levels in the vicinity of the project in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies? Less-than-Significant Impact with Mitigation Incorporated No permanent noise increase would result from the project. The bridge would be retrofit for enhanced safety and operations would continue as is, with a similar level of activity and use to the present. During construction, however, a temporary increase in ambient noise is anticipated.
Noise generated by project-related construction activities would be a function of the noise levels generated by individual pieces of construction equipment, the type and amount of equipment operating at any given time, the timing and duration of construction activities, the proximity of nearby sensitive land uses, and the presence or lack of shielding at these sensitive land uses.
Construction noise levels would vary on a day-to-day basis during each phase of construction, depending on the specific task being completed. Each construction phase would require a different combination of construction equipment necessary to complete the task and differing usage factors for such equipment. Construction noise would primarily result from the operation of heavy construction equipment and the arrival and departure of heavy-duty trucks.
The Town’s General Plan shows that the existing noise environment in the vicinity of the project site would typically be characterized by ambient noise levels less than 60 dBA Ldn. Activities associated with the earthwork and retrofit phases of the project would generate hourly average noise levels up to 85 dBA Leq at a distance of 50 feet. Maximum instantaneous noise levels would reach 85 dBA Lmax at 50 feet. This retrofit project does not include pile driving activities, which are considered generally to be one of the most excessive noise-generating construction activities. Construction-generated noise levels drop off at a rate of about 6 dBA per doubling of the distance between the source and receptor; therefore, the noise levels calculated at 50 feet would be about 6 dBA less at 100 feet and 12 dBA less at 205 feet. Shielding provided by buildings or terrain would result in even lower construction noise levels at distant receptors.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 78 Construction-related vehicles traveling to and from the project site would generate worst-hour noise levels of approximately 57 dBA Leq at a distance of 50 feet from the center of Creek Road, assuming that the peak number of trucks expected on any one day would be approximately eight one-way truck trips per hour and that up to 20 one-way vehicle trips would occur per hour for the construction crew.
Although the construction of the proposed project would elevate noise levels at nearby noisesensitive land uses by 25 dBA or more above ambient daytime conditions, Mitigation Measure NOISE-1 would require implementation of best management practices as suggested in the Town’s General Plan to reduce noise from construction activities at nearby sensitive land uses. As stated in § 8.20.079 of the Town of Fairfax Municipal Code, “the operation of any tools or equipment used in construction, drilling, repair, alteration or demolition work, mechanically powered saw, sander, drill, grinder, lawn or garden tool, leaf blower, or similar tool between 8:00 a.m. and 8:00 p.m. on weekdays and 9:00 a.m. and 8:00 p.m. on weekends are exempt (from the provisions contained in § 8.20.050).” Therefore, temporary noise generated during construction would not generate noise levels that are in excess of local standards or established in the local noise ordinance. Noise impacts would be minimized to the degree feasible with the implementation of Mitigation Measure NOISE-1, and no permanent noise impact would result from the project.
Mitigation Measure NOISE-1: Construction Noise
In order to comply with Policy N-3.1.4, the Town of Fairfax has developed a list of Standard Controls. The project shall comply with the following measures:
1. Limit construction to the hours of 8:00 a.m. to 5:00 p.m. on weekdays, and 9:00 a.m. to 5:00 p.m. on Saturdays, with no noise-generating construction on Sundays or Holidays.
2. Control Noise from construction workers’ radios to the point where they are not audible at existing residences that border the project site.
3. Equip all internal combustion engine-driven equipment with mufflers which are in good condition and appropriate for the equipment.
4. Utilize quite models of air compressors and other stationary noise sources where technology exists.
5. Locate stationary noise-generating equipment as far as possible from sensitive receptors when sensitive receptors adjoin or are near a construction project area.
6. Prohibit unnecessary idling of internal combustion engines.
7. Notify residents adjacent to the project site of the construction schedule in writing.
8. Designate a noise disturbance coordinator who would be responsible for responding to any local complaints about construction noise. The disturbance coordinator would determine the cause of the noise complaints (e.g., starting too early, bad mufflers) and institute reasonable measure warranted to correct the problem. Conspicuously post a telephone number for the disturbance coordinator at the construction site.
In addition, the project shall follow the standard construction noise requirements regulated by Caltrans Sections 7-1.01I and 14-8.02 of the Standard Specifications which states the following:
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 79 1. Do not exceed 86 dBA at 50 feet from the job site activities from 9 p.m. to 6 a.m.
2. Equip an internal combustion engine with the manufacturer-recommended muffler. Do not operate an internal combustion engine on the job site without the appropriate muffler.
b) Generation of excessive groundborne vibration or groundborne noise levels? Less-than-Significant Impact
The construction of the project may generate perceptible vibration when heavy equipment or impact tools (e.g., jackhammers, hoe rams) are used. Construction activities would include site preparation work, dewatering, excavation, retrofit reinforcement, and paving. The proposed project would not require pile driving, which can cause excessive vibration.
For structural damage, Caltrans recommends a vibration limit of 0.5 in/sec Peak Particle Velocity (PPV) for buildings structurally sound and designed to modern engineering standards, 0.3 in/sec PPV for buildings that are found to be structurally sound but where structural damage is a major concern, and a conservative limit of 0.08 in/sec PPV for ancient buildings or buildings that are documented to be structurally weakened. All buildings in the project vicinity are assumed to be structurally sound, but these buildings may or may not have been designed to modern engineering standards. No ancient buildings or buildings that are documented to be structurally weakened are known to exist in the area. Therefore, ground-borne vibration levels exceeding 0.3 in/sec PPV would have the potential to result in a significant vibration impact.
Table 6 presents typical vibration levels that could be expected from construction equipment at a distance of 25 feet. Project construction activities, such as drilling, the use of jackhammers, rock drills and other high-power or vibratory tools, and rolling stock equipment (tracked vehicles, compactors, etc.) may generate substantial vibration in the immediate vicinity. Jackhammers typically generate vibration levels of 0.035 in/sec PPV, and drilling typically generates vibration levels of 0.09 in/sec PPV at a distance of 25 feet. Vibration levels would vary depending on soil conditions, construction methods, and equipment used. The single-family residences in the immediate project vicinity range from 50 to 205 feet; at these distances, vibration levels would be expected to be 0.1 in/sec PPV or less, below the 0.3 in/sec PPV significance threshold. This would be a less-than-significant impact and would not require mitigation.
Table 6. Vibration Source Levels for Construction Equipment EQUIPMENT PPV AT 25 FT.
(IN/SEC)
APPROXIMATE LV
AT 25 FT. (VDB)
Pile Driver (Impact)
upper range 1.158 112
typical 0.644 104
Pile Driver (Sonic)
upper range 0.734 105
typical 0.170 93
Clam shovel drop 0.202 94
Hydromill (slurry wall)
in soil 0.008 66
in rock 0.017 75
Vibratory Roller 0.210 94
Hoe Ram 0.089 87
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 80 EQUIPMENT PPV AT 25 FT.
(IN/SEC)
APPROXIMATE LV
AT 25 FT. (VDB)
Large bulldozer 0.089 87
Caisson drilling 0.089 87
Loaded trucks 0.076 86
Jackhammer 0.035 79
Small bulldozer 0.003 58
Source: Transit Noise and Vibration Impact Assessment, United States Department of Transportation, Office of Planning and Environment, Federal Transit Administration, May 2006. c) For a project located within the vicinity of a private airstrip or an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the project expose people residing or working in the project area to excessive noise levels?
No Impact
The project area is not within the vicinity of a private or public airstrip or within the vicinity of an airport land use plan. Therefore, no impacts associated with excessive private airplane noise would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 81 4.2.14 Population and Housing
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Induce substantial unplanned population
growth in an area, either directly (for
example, by proposing new homes and
businesses) or indirectly (for example,
through extension of roads or other
infrastructure)?
b) Displace substantial numbers of existing
people or housing, necessitating the
construction of replacement housing
elsewhere?
ENVIRONMENTAL SETTING
The project site is located in a residential neighborhood community of the Town of Fairfax. The General Plan land use designations surrounding the project site include low density residential and medium density residential. Surrounding land uses include San Anselmo Creek and residential homes.
DISCUSSION OF IMPACTS
a) Induce substantial unplanned population growth in an area, either directly (for example, by proposing new homes and businesses) or indirectly (for example, through extension of roads or other infrastructure)?
No Impact
The proposed project would rehabilitate an existing bridge. No residential development or permanent employment opportunities would result from project implementation. No population growth is anticipated as a result of the project. No impact would occur. b) Displace substantial numbers of existing people or housing, necessitating the construction of replacement housing elsewhere?
No Impact
The proposed project would improve the existing Creek Road Bridge. No houses are planned for removal and no people would be displaced. No impact would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 82 4.2.15 Public Services
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times, or other performance objectives for any of the public services:
Fire protection?
Police protection?
Schools?
Parks?
Other public facilities?
ENVIRONMENTAL SETTING
The Ross Valley Fire Department (RVFD) currently provides fire protection and emergency response services to the communities of Ross, San Anselmo, Sleepy Hollow and Fairfax. The RVFD operates four fire stations. RVFD Station 21 provides fire protection and paramedic services to the project site. Station 21 is located at 10 Park Road. The project site is within approximately one mile of the station.
The Town of Fairfax Police Department (FPD) provides police protection services to the project site. The FPD employs 11 full-time Police Officers, 2 Reserve Police Officers, 4 full time Police Dispatchers, 1 Community Services Technician and 4 part time Police Dispatchers. The FPD station is located at 44 Bolinas Road. The project site is within approximately one mile of the station.
There is only a single school in the immediate vicinity of the project site. The Sir Francis Drake High School is approximately one mile northeast of the project site.
The recreational parks within the general vicinity of the project site are Contratti Park Baseball Field and Doc Edgar Park.
DISCUSSION OF IMPACTS
a) Result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times, or other performance objectives for any of the public services:
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 83 • Fire Protection?
• Police Protection?
• Schools?
• Parks?
• Other Public Facilities?
The project would not rely on the addition or alteration of any public services. No residential or commercial construction is proposed by the project. The project would not increase population in the Town that could result in additional demands for public services and therefore would not require the construction of new public service facilities or the expansion of existing public service facilities. As such, the project would not result in significant physical impacts associated with the provision of new or physically altered governmental facilities. i) Fire protection?
No Impact
The RVFD would continue to provide fire protection services to the project site upon development. As discussed in Impact 4.14-a, the project would not include construction of any residential structures or result in an increase in residential population. Therefore, the project would not induce population growth which would necessitate the expansion of existing or construction of new fire protection facilities.
Therefore, no impact would occur related to fire protection services. ii) Police protection?
Less-than-Significant Impact
During construction, a minor demand for additional FPD services may occur during the project’s construction phase. Such services include, but may not be limited to, consultation during plan check, routine surveillance of the construction site by regular patrol units, potential investigations of theft of or vandalism to construction equipment and materials, and enforcement of local speed limits near the construction site. These services are routine for construction projects and would not generate demand for police services which would require the need for new or expanded police facilities. The operational phase of the proposed project would not result in increased service call responses from the FPD, due to the lack of residential or commercial development. It is not anticipated that the project would necessitate the expansion of existing or construction of new police protection facilities.
Therefore, project impacts related to police protection services would be less than significant.
iii) Schools?
No Impact
As discussed in Impact 4.14 (a), the project would not include construction of any residential structures. The project would not result in an increase of population that would require additional school facilities. There would be no impact.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 84 iv) Parks?
No Impact
As discussed in Impact 4.14 (a), the project would not include construction of any residential structures. As the project would not induce population growth, the project would not create a need for additional park or recreational services. There would be no impact.
v) Other public facilities?
No Impact
As discussed in Impact 4.14 (a), the project would not include construction of any residential structures. As the project would not induce population growth, the project would not create a need for other public facilities including public libraries, public hospitals and medical centers, and community centers. There would be no impact.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 85 4.2.16 Recreation
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Increase the use of existing neighborhood and
regional parks or other recreational facilities
such that substantial physical deterioration of
the facility would occur or be accelerated?
b) Include recreational facilities or require the
construction or expansion of recreational
facilities which might have an adverse
physical effect on the environment?
ENVIRONMENTAL SETTING
The recreational parks within the general vicinity of the project site are Contratti Park Baseball Field and Doc Edgar Park. Doc Edgar Park is the closest recreational facility to the site located approximately 0.2 miles away. The park contains amenities such as benches, dog walking facilities, and a grassy field.
DISCUSSION OF IMPACTS
a) Increase the use of existing neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facility would occur or be accelerated?
No Impact
The proposed project would not involve any additional housing or businesses that could increase the use of recreational facilities in the project area. The project would rehabilitate an existing bridge. Physical deterioration of the recreational facilities would not be affected by the project.
No impact would occur.
b) Include recreational facilities or require the construction or expansion of recreational facilities which might have an adverse physical effect on the environment? No Impact
The project would not require the construction or expansion of recreational facilities which might have an adverse physical effect on the environment. The purpose of the project is to rehabilitate existing bridges. No impact regarding recreational facilities would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 86 4.2.17 Transportation
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Conflict with a program, plan, ordinance or
policy addressing the circulation system,
including transit, roadway, bicycle and
pedestrian facilities?
b) Conflict or be inconsistent with CEQA
Guidelines section 15064.3, subdivision (b)?
c) Substantially increase hazards due to a
geometric design feature (e.g., sharp curves
or dangerous intersections) or incompatible
uses (e.g., farm equipment)?
d) Result in inadequate emergency access?
ENVIRONMENTAL SETTING
The proposed project includes repairs to the existing Creek Road Bridge within the Town of Fairfax. Major streets in Fairfax are classified as arterial, collector, and local. Arterials carry regional trips and traffic between areas of the Town while providing access to major traffic generators. Collector streets link neighborhoods to arterial streets and carry traffic for short segments in residential and commercial areas, while local streets provide direct access to parcels and residences. Many streets in the Town Center serve both collector and local street functions.
All two-way roadways are two-lane, though on many streets, especially on the hillsides, it is impossible to pass oncoming traffic at the narrowest points. Creek Road and Dominga Avenue are designated “Local” and Bolinas Road is designated as “Arterial” within the General Plan.
There are no “Principal Arterial” Roadways, as designated by the Congestion Management Program, in or adjacent to the project site (Transportation Authority of Marin 2021). There are no intersections on either approach to the Creek Road Bridge.
DISCUSSION OF IMPACTS
a) Conflict with a program, plan, ordinance or policy addressing the circulation system, including transit, roadway, bicycle and pedestrian facilities? Less-than-Significant Impact with Mitigation Incorporated The bridge will be closed off to motorized, pedestrian and bicycle traffic for approximately 4 months, the length of the dry season (April 15-October 15). An approximately 0.5-mile detour would be provided via Porteous Avenue and Creek Road and would result in minimal delays (approximately 1 minute by car and eleven minutes by foot). Permanent on-street parking will not be impacted. Temporary parking loss in the active work zone may occur where the construction work is active.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 87 The project would not significantly affect alternative transportation routes in the project area.
Temporary construction impacts would result in temporary limited access for motorized and nonmotorized vehicles, and pedestrians. Mitigation Measure TRANS-1 would reduce these impacts to less than significant.
Mitigation Measure TRANS–1: Traffic Control Plan
Prior to construction activities at the project site, a traffic control plan shall be prepared for implementation throughout project construction. The traffic control plan shall be subject to review and approval by the Town prior to implementation. The traffic control plan shall contain the provisions such as the following:
1. At least one week prior to the commencement of construction work, the Town shall require the contractor to provide project information signs to notify drivers of the upcoming project and potential delays.
2. Lane closure and traffic control during project construction will conform to the California Manual on Uniform Traffic Control Devices (CAMUTCD), Caltrans standard plans and specifications.
3. The contractor will install advance warning signs to alert bicyclists and motorists of the construction work zone and lane closures. Advance warning signs may be reflective signs, changeable message boards, cones, and barricades. All temporary signage related to construction work shall be removed by the construction contractor after project construction work has finished.
4. Flagging and other means of traffic control will be required to allow for the safe movement of traffic through the work zone. The contractor will provide flaggers to temporarily hold traffic for staging equipment or construction.
5. Work shall be performed in a manner that is least disruptive to the public. The contractor will consult and coordinate with the property owner if access will be affected.
6. The Town shall coordinate with local emergency services (i.e., the police and fire departments) to inform them of temporary construction work and potential road closures. Emergency access shall be maintained throughout the project duration.
With implementation of a traffic control plan and the temporary nature of construction-related traffic, impacts on traffic would be less than significant. b) Conflict or be inconsistent with CEQA Guidelines section 15064.3, subdivision (b)? Less-than-Significant Impact
According to CEQA Guidelines Section 15064.3, Subdivision (b), a project’s effects on automobile delay do not constitute significant environmental impacts. Instead, vehicle miles traveled (VMT) is the most appropriate measure of the project’s impact on transportation; and projects that would reduce VMT in their vicinity should be considered to have a less-than-significant transportation impact.
The project would lead to a temporary, minimal increase in VMT due to the transportation of construction equipment and personnel, as well as a temporary, small increase in VMT due to the road closure and detour during construction. Construction equipment would be staged near the Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 88 project site, minimizing construction VMT and making this increase less than significant. The temporary detour would impact a small number of residents and the likely detour routings to be established would not appreciably increase the total distances traveled.
In the long-term, the project would not lead to any increase in VMT. The replacement bridge would not contain a new path or additional features which might accommodate increased vehicles. As no substantial increases in VMT are anticipated to result from the project, the project would be consistent with CEQA Guidelines Section 15064.3, subdivision (b); and a less than significant impact would occur.
c) Substantially increase hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)? No Impact
The project would not involve new road construction or activities that could increase hazards due to a design feature or incompatible uses. Adequate sight distance would be available for motorists to access and depart the project Area. The proposed project would include seismic retrofit of an existing bridge and operation of the proposed project would return to existing conditions.
d) Result in inadequate emergency access?
Less-than-Significant Impact with Mitigation Incorporated The bridge will be closed off to emergency service vehicles (EMS) during the duration of construction. EMS traffic would be required to follow detours around the project site. However, as stated above, the detour route is short in duration and would cause slight to no delays. The construction contractor shall coordinate with law enforcement and emergency service providers prior to the start of construction to ensure minimal disruption to service during construction.
Implementation of Mitigation Measure TRANS-1 would reduce temporary construction related impacts to emergency access for Creek Road to less-than-significant by providing proper detour signage and warnings.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 89 4.2.18 Tribal Cultural Resources
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is:
i) Listed or eligible for listing in the California
Register of Historical Resources, or in a local
register of historical resources as defined in
Public Resources Code section 5020.1(k)?
ii) A resource determined by the lead agency, in
its discretion and supported by substantial
evidence, to be significant pursuant to criteria
set forth in subdivision (c) of Public Resources
Code section 5024.1? In applying the criteria
set forth in subdivision (c) of Public Resources
Code section 5024.1, the lead agency shall
consider the significance of the resource to a
California Native American tribe.
ENVIRONMENTAL SETTING
A description of the environmental setting related to tribal cultural resources can be found in Section 4.2.5, Cultural Resources.
REGULATORY SETTING
Tribal Cultural Resources Assembly Bill 52 (AB 52)
AB 52 (Chapter 532, Statutes 2014) required an update of the CEQA Guidelines to include questions related to impacts to tribal cultural resources. AB 52 establishes a consultation process with all California Native American Tribes on the Native American Heritage Commission List, Federal and Non-Federal Recognized Tribes. AB 52 also establishes a new class of resources:
Tribal Cultural Resources. Key components of AB 52 include consideration of Tribal Cultural Values in determination of project impacts and mitigation and required Tribal notice and meaningful consultation.
PRC Section 21080.3.2(b) states that consultation ends when either 1) parties agree to mitigation measures or avoid a significant effect on a tribal cultural resource, or 2) a party, acting in good faith and after reasonable effort concludes that mutual agreement cannot be reached.
State of California Public Resources Code
Section 21074 of the PRC defines historical resources related to tribal cultural resources. a) “Tribal cultural resources” are either of the following:
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 90 a. Sites, features, places, cultural landscapes, sacred places, and objects with cultural value to a California Native American tribe that are either of the following:
A. Included or determined to be eligible for inclusion in the California Register of Historical Resources.
B. Included in a local register of historical resources as defined in subdivision (k) of Section 5020.1.
b. A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Section 5024.1. In applying the criteria set forth in subdivision (c) of Section 5024.1 for the purposes of this paragraph, the lead agency shall consider the significance of the resource to a California Native American tribe. b) A cultural landscape that meets the criteria of subdivision (a) is a tribal cultural resource to the extent that the landscape is geographically defined in terms of the size and scope of the landscape.
c) A historical resource described in Section 21084.1, a unique archaeological resource as defined in subdivision (g) of Section 21083.2, or a “nonunique archaeological resource” as defined in subdivision (h) of Section 21083.2 may also be a tribal cultural resource if it conforms with the criteria of subdivision (a).
Section 5020.1(k) defines “Local register of historical resources” as a list of properties officially designated or recognized as historically significant by a local government pursuant to a local ordinance or resolution.
Section 5024.1 is the establishment of the California Register of Historical Resources (California Register).
Native American Consultation
Pursuant to AB 52, on January 8, 2026, the Town sent a letter to Buffy McQuillen of the Federated Indians of Graton Rancheria soliciting the Tribe’s input on the project. The Town followed up via email on February 3, 2026 to confirm receipt of the letter and solicit input on the project. No response has been received to date.
DISCUSSION OF IMPACTS
a) Cause a substantial adverse change in the significance of a tribal cultural resource, defined in Public Resources Code section 21074 as either a site, feature, place, cultural landscape that is geographically defined in terms of size and scope of the landscape, sacred place, or object with cultural value to a California Native American tribe, and that is:
i) Listed or eligible for listing in the California Register of Historical Resources, or in a local register of historical resources as defined in Public Resources Code section 5020.1(k)?
ii) A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 91 subdivision (c) of Public Resources Code section 5024.1? In applying the criteria set forth in subdivision (c) of Public Resources Code section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe.
Less-than-Significant Impact with Mitigation Incorporated In accordance with AB 52, Graton Rancheria was notified of the project on January 8, 2026, after having been present on site for the subsurface cultural resources investigation completed in 2023 and having been consulted about the project prior to those investigations. The Town followed up on the AB 52 notice after it was sent; however, no responses were received from Graton Ranchera, therefore no further consultation was undertaken beyond that completed in past years.
No tribal cultural resources have been identified within the project site.
Although Graton Rancheria was not responsive to the project notification letter sent pursuant to AB 52, the Town is aware that the tribe previously expressed interest in tribal monitoring for the project during the National Environmental Policy Act (NEPA) review process. As such, the Mitigation Measure TCR-1 will be implemented, which requires the Town to reach out to Graton Rancheria one more time no less than 30 days prior to construction to confirm whether they would like to send a tribal monitor to observe project excavation work. Implementation of Mitigation Measure TCR-1, along with CUL-1 and CUL-2, would ensure that the project would not have a significant adverse effect on tribal cultural resources. The impact would be less than significant with mitigation incorporated.
Mitigation Measure TCR-1. Outreach to the Federated Indians Graton Rancheria The Town of Fairfax shall reach out to Graton Rancheria no less than 30 days prior to construction to confirm whether they would like to have a tribal monitor present during excavation activities. If requested by Graton Rancheria, the Town shall arrange to have a tribal monitor present during excavation work.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 92 4.2.19 Utilities and Service Systems
Would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Require or result in the relocation or
construction of new or expanded water,
wastewater treatment or storm water
drainage, electric power, natural gas, or
telecommunications facilities, the
construction or relocation of which could
cause significant environmental effects?
b) Have sufficient water supplies available to
serve the project and reasonably foreseeable
future development during normal, dry, and
multiple dry years?
c) Result in a determination by the wastewater
treatment provider which serves or may serve
the project that it has adequate capacity to
serve the project’s projected demand in
addition to the provider’s existing
commitments?
d) Generate solid waste in excess of state or
local standards, or in excess of the capacity
of local infrastructure, or otherwise impair
the attainment of solid waste reduction
goals?
e) Comply with federal, state, and local
management and reduction statutes and
regulations related to solid waste?
ENVIRONMENTAL SETTING
The project site is located within a developed residential area of the Town that provides all utilities and services (e.g., water supply and distribution, sewage distribution and treatment, storm drainage facilities, and solid waste management). Electrical and other utility lines are also located along the roads, either underground or aboveground. The proposed project includes seismic retrofit of an existing bridge. The construction phase of the project would require use of solid waste disposal. There are existing water lines and storm drainage pipes running along the bridge.
Water Service
Established in 1912, the MMWD provides drinking water to 187,500 customers in central and southern Marin County. Seventy-five percent of the water comes from more than 21,000 acres of protected watershed on Mt. Tamalpais and in the grassy hills of west Marin. Rainfall from these Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 93 watersheds flows into one of MMWD’s seven reservoirs. This reservoir water is then treated at one of the district’s potable water treatment plants before traveling to customers’ homes and businesses.
Storm Drainage
The 28-square mile Corte Madera watershed extends from Mt. Tamalpais and White’s Hill through the communities of Fairfax, Sleepy Hollow, San Anselmo, Ross, Kentfield, Greenbrae, Larkspur, and Corte Madera to San Francisco Bay. The watershed includes 44 miles of stream channels. Ross Creek drains the northern slope of Mt. Tamalpais; San Anselmo Creek and its tributaries drain the northwestern portion of the watershed. The two channels join to form Corte Madera Creek, which continues through more than a mile of concrete-lined channel past the confluences of Larkspur and Tamalpais Creeks and into the salt marsh at the mouth.
The principal natural hydrological sources for the project site are creek flows, direct precipitation and surface run-off from adjacent lands. San Anselmo Creek flows though the project site towards the north/northeast. Just north of the project site, Deer Creek joins San Anselmo Creek.
Roughly one quarter of a mile to the north, it joins Fairfax Creek and turns east, eventually flowing into Corte Madera Creek, then San Francisco Bay, and the Pacific Ocean. In wet years, the creek at this location is perennial. At the time of the fieldwork, in a drought year, the flows were low.
The storm water drainage pipes within the Town are maintained by the Town of Fairfax Department of Public Works.
Solid Waste
The Marin Sanitary Service provides waste disposal services for the site. According to the Marin Countywide Plan, there are two permitted landfills operate in the county. The Redwood Landfill would be the most likely to service the project’s solid waste disposal needs.
DISCUSSION OF IMPACTS
a) Require or result in the relocation or construction of new or expanded water, wastewater treatment or storm water drainage, electric power, natural gas, or telecommunications facilities, the construction or relocation of which could cause significant environmental effects?
Less-than-Significant Impact
An existing 6” waterline at the east abutment and possibly a 4” PVC waterline at the west abutment could interfere with the proposed waffle slabs. If this is the case, these utilities would be relocated by MMWD. Additionally, a 12”-diameter corrugated metal pipe storm drain pipe crossing Creek Road and daylighting at the south creek bank slightly downstream of the bridge interferes with the abutment’s waffle slab at the east end of the bridge and would be redirected around the slab.
This would take place by abandoning the current pipe, excavating a sloped trench in the street and the adjacent creek bank and placing a new length of 12” corrugated metal pipe below the surface to daylight at the current location. The trench would be covered back up and the street pavement restored. Where the existing pipe daylights currently, the creek bank has been eroded.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 94 A 6’ wide by approximately 20’ long by 2’ deep course of riprap would be placed flush with the surface of the creek bank just below where the flows exits the pipe in order to stop and prevent further bank erosion.
The project would improve storm water drainage in the area surrounding the project area by abandoning the current pipe and redirecting a new storm drain pipe. The addition of rip rap near the existing pipe would reduce ongoing creek bed erosion. As discussed in other sections of this report, all potentially significant impacts related to trenching and construction within the creek would be reduced to less-than-significant levels via the implementation of Mitigation Measure BIO-4, which provides measures to minimize impacts to creek habitat from use of power tools in the creek bed.
No other public utilities such as wastewater treatment, electric power, natural gas, or telecommunications facilities would need be constructed, expanded, or relocated. As impacts associated with the relocation of waterlines would be mitigated to less-than-significant levels and no other impacts to public facilities would occur, the project would not cause significant environmental effects through construction or relocation of any such facilities, and impacts would be less than significant with mitigation incorporated.
b) Have sufficient water supplies available to serve the project and reasonably foreseeable future development during normal, dry, and multiple dry years? Less-than-Significant Impact
The proposed project would rehabilitate an existing bridge. No water is anticipated to be needed during operation. Water supply for dust control during construction would be provided by existing service providers with sufficient supplies to serve the project’s small, temporary water needs. Therefore, there would be sufficient water supplies to serve the project and reasonably foreseeable future development during normal, dry, and multiple dry years; and impacts would be less than significant.
c) Result in a determination by the wastewater treatment provider which serves or may serve the project that it has adequate capacity to serve the project’s projected demand in addition to the provider’s existing commitments?
No Impact
The project would not generate wastewater and would not impact wastewater treatment or capacity. No new distribution facilities would be constructed or needed as part of the project.
Therefore, no impact to wastewater capacity would occur. d) Generate solid waste in excess of state or local standards, or in excess of the capacity of local infrastructure, or otherwise impair the attainment of solid waste reduction goals? Less-than-Significant Impact
Local waste reduction efforts are overseen by Zero Waste Marin, a joint powers authority comprised of representatives of Marin County and each of the County’s constituent cities. Zero Waste Marin works with businesses and residents to reduce solid waste and move towards Marin County’s goal of zero waste by 2025. Among these efforts, Zero Waste Marin encourages the use of certified disposal facilities during demolition and construction projects to ensure that Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 95 materials are recycled to the fullest extent feasible, in keeping with state requirements that most construction and demolition projects divert 65% of waste.
The project would generate a small quantity of solid waste during construction, but all generated waste would be properly disposed or recycled in an approved landfill or disposal facility with capacity to receive the waste. Solid waste would be disposed of at the Redwood Landfill, a certified landfill. Redwood Landfill is anticipated to have capacity through 2025; so the project’s solid waste would be insufficient to exceed remaining capacity. Further, Zero Waste Marin encourages disposal at certified facilities to ensure that materials are recycled to the greatest extent feasible. By recycling at Redwood Landfill, the project would maximize its potential for recycling, in keeping with state and local waste reduction efforts.
As the project would dispose of its solid waste at a certified facility with adequate permitted capacity, the project would not generate solid waste in excess of state or local standards or local infrastructure or otherwise impair the attainment of solid waste reduction goals. Thus, a lessthan-significant impact would occur. e) Comply with federal, state, and local management and reduction statutes and regulations related to solid waste?
Less-than-Significant Impact
Marin County has a goal of zero waste by 2025. The joint powers authority overseeing zero waste efforts, Zero Waste Marin, encourages disposal at a certified facility during construction and demolition to comply with state waste reduction requirements. The project would dispose of solid waste at Redwood Landfill, a certified landfill. The project would therefore comply with local and state requirements for solid waste reduction. No federal solid waste reduction requirements applicable to the project were identified. As the project would comply with local and state requirements and no federal requirements were identified, a less-than-significant impact would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 96 4.2.20 Wildfire
If located in or near state responsibility areas
or lands classified as very high fire hazard
severity zones, would the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Substantially impair an adopted emergency
response plan or emergency evacuation plan?
b) Due to slope, prevailing winds, and other
factors, exacerbate wildfire risks, and thereby
expose project occupants to pollutant
concentrations from a wildfire or the
uncontrolled spread of a wildfire?
c) Require the installation or maintenance of
associated infrastructure (such as roads, fuel
breaks, emergency water sources, power lines
or other utilities) that may exacerbate fire risk
or that may result in temporary or ongoing
impacts to the environment?
d) Expose people or structures to significant risks,
including downslope or downstream flooding
or landslides, as a result of runoff, post-fire
slope instability, or drainage changes?
ENVIRONMENTAL SETTING
Pursuant to Government Code Section 51175-89, the California Department of Fire and Forestry (CAL FIRE) recommends Fire Hazard Severity Zones (FHSZ) throughout the state. These are mapped taking relevant factors such as fuels, terrain, and weather into account. FHSZ are described based on their potential to cause building ignition. Areas assessed for fire hazards throughout the state are categorized as local responsibility areas and state responsibility areas depending on the entity responsible for fire protection.
The Ross Valley Fire Department (RVFD) currently provides fire protection and emergency response services to the communities of Ross, San Anselmo, Sleepy Hollow and Fairfax. The RVFD operates four fire stations. RVFD Station 21 provides fire protection and paramedic services to the project site. The project site is within approximately one mile of Station 21, located at 10 Park Road in Fairfax.
CAL FIRE classifies the site and its surroundings as being within a High FHSZ in the local responsibility area (CAL FIRE 2025). The nearest state responsibility area is approximately 0.5 miles from of the project site on the southern border of Fairfax. The nearest Very High FHSZ is in the state responsibility area located approximately 0.5 miles west of the project site.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 97 DISCUSSION OF IMPACTS
a) Substantially impair an adopted emergency response plan or emergency evacuation plan?
Less-than-Significant Impact with Mitigation Incorporated The project site is not within a state responsibility area or a very high fire hazard severity zone but is near a state responsibility area. During construction the Creek Road Bridge would be closed, and detours would be established to and away from the bridge via Creek Road and Porteous Avenue in the direction away from the bridge towards Bolinas Road. Mitigation Measure TRANS-1 would address lane closures and traffic control during construction and mitigate impacts to emergency response and evacuation to less-than-significant levels. Thus, the project would not substantially impair an adopted emergency response or evacuation plan, and impacts would be less than significant with mitigation incorporated. b) Due to slope, prevailing winds, and other factors, exacerbate wildfire risks, and thereby expose project occupants to pollutant concentrations from a wildfire or the uncontrolled spread of a wildfire?
Less-than-Significant Impact
The project could temporarily exacerbate existing wildfire risk through the presence of motorized construction equipment powered by flammable fuels. However, compliance with construction site best management practices as outlined in Mitigation Measures AIR-1 and HYDRO-1 would reduce the potential for fuel ignition. Any increased risk would be small and temporary and would not substantially increase the likelihood of exposure to pollutants from wildfire or uncontrolled spread of wildfire. In the long term, the project would not alter the operations of the existing bridge and no changes to the structure would exacerbate wildfire risk. As fire risk increase during construction would be minimal and there would be no permanent risk increase, the project would not exacerbate wildfire risk, and impacts would be less than significant. c) Require the installation or maintenance of associated infrastructure (such as roads, fuel breaks, emergency water sources, power lines or other utilities) that may exacerbate fire risk or that may result in temporary or ongoing impacts to the environment? No Impact
The project is a bridge seismic retrofit that does not require the construction of any associated infrastructure such as roads, fuel breaks, emergency water sources, power lines, or other utilities that may exacerbate fire risk or result in temporary or ongoing impacts to the environment. As such, no impact would occur.
d) Expose people or structures to significant risks, including downslope or downstream flooding or landslides, as a result of runoff, post-fire slope instability, or drainage changes?
Less-than-Significant Impact
Downstream areas roughly 0.6 miles south of the project site are considered moderately high fire hazard severity zones in the state responsibility area. These areas could be vulnerable to slope Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 98 instability following a fire. However, the project would not alter drainage patterns or result in runoff in these areas. The bridge has been designed to clear the high-water mark, even during high flow events. Although there are areas prone to wildfire downstream, as detailed above the project would not alter the chance of downstream flooding or landslides. Thus, a less than significant impact would occur.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 99 4.2.21 Mandatory Findings of Significance
Does the project:
Potentially
Significant
Impact
Less-thanSignificant
Impact with
Mitigation
Incorporated
Less-thanSignificant
Impact
No
Impact
a) Have the potential to substantially degrade
the quality of the environment, substantially
reduce the habitat of a fish or wildlife
species, cause a fish or wildlife population to
drop below self-sustaining levels, threaten to
eliminate a plant or animal community,
substantially reduce the number or restrict
the range of a rare or endangered plant or
animal or eliminate important examples of
the major periods of California history or
prehistory?
b) Have impacts that are individually limited,
but cumulatively considerable?
(“Cumulatively considerable” means that the
incremental effects of a project are
considerable when viewed in connection with
the effects of past projects, the effects of
other current projects, and the effects of
probable future projects)?
c) Have environmental effects that will cause
substantial adverse effects on human beings,
either directly or indirectly?
DISCUSSION OF IMPACTS
a) Does the project have the potential to substantially degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self-sustaining levels, threaten to eliminate a plant or animal community, substantially reduce the number or restrict the range of a rare or endangered plant or animal or eliminate important examples of the major periods of California history or prehistory?
Less-than-Significant Impact with Mitigation Incorporated The incorporation of the mitigation measures included in Section 4.2.4 Biological Resources would reduce potential impacts to fish, wildlife, plants, and habitat to a less-than-significant level. The project site does not contain any resource listed in, or determined to be eligible by, the State Historical Resource Commission and does not contain a resource included in a local register of historic resources or identified as significant in a historical survey. Additionally, the project site does not contain any object, building, structure, site, area, place, record, or manuscript that a lead agency determined to be historically significant. However, cultural resources could potentially be uncovered during construction. Mitigation measures included in Section 4.2.5, Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 100
Cultural Resources and Section 4.2.15, Tribal Cultural Resources, would reduce potential impacts to be a less-than-significant level.
b) Does the project have impacts that are individually limited, but cumulatively considerable? (“Cumulatively considerable” means that the incremental effects of a project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects)? Less-than-Significant Impact with Mitigation Incorporated Section 15130 of the CEQA Guidelines requires an evaluation of potential environmental impacts when the project’s incremental effect is cumulatively considerable. “Cumulatively considerable” means that the incremental effects of an individual project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects. These impacts can result from a combination of the proposed project together with other projects causing related impacts. The cumulative impact from several projects is the change in the environment which results from the incremental impact of the project when added to other closely related past, present, and reasonably foreseeable probable future projects.
The bridge repairs would not change the use of the roadway or the bridge. Therefore, project impacts that could contribute to a cumulative impact are predominately short-term and temporary construction related impacts focused within the project vicinity. The Town’s paving program plans repaving work on Bolinas Road during Fiscal Year 2028-2029 from Broadway to Deer Park Villa, which is in proximity to the Creek Road Bridge. Creek Road is also planned for repaving in Fiscal Year 2028-2029 from Blackberry Lane to Bolinas Road. The Town, as manager of each of these projects as well as the proposed project, would ensure that work is appropriately staggered so that cumulative construction impacts do not occur. There are no other construction projects planned within the immediate vicinity of the project site which could contribute to a cumulatively considerable impact resulting from project construction.
The project would implement mitigation measures to ensure that significant impacts related to air quality, biological resources, cultural resources, geology and soils, hazards and hazardous materials, hydrology and water quality, noise, transportation, and tribal cultural resources would not occur.
Mitigation Measure AIR-1 includes the implementation of BAAD-recommended dust control measures to ensure that the project would not generate levels of fugitive dust that would contribute to a cumulative air quality impact. The BAAD does not establish significance thresholds for fugitive dust emissions but considers projects that implement the BAADrecommended BMPs to have a less-than-significant impact related to cumulative fugitive dust emissions. The project would cause a temporary increase in emissions in the area during construction; however, operation of the project would not constitute a new source of emissions or an increase in emissions. The post-project emissions conditions would be similar to existing conditions. Therefore, the project would not result in a cumulative air quality impact.
Mitigation Measures BIO-1a, BIO-1b, and BIO-2 would ensure that the project would not result in a significant impact to special-status wildlife species during construction. Mitigation Measure BIO-1a requires measures to ensure that the project would not result in permanent impacts to Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 101
steelhead individuals or their habitat. Measures to avoid temporary impacts include preparation of an Accidental Spill Prevention and Cleanup Plan, implementation of a fish salvage plan, avoidance of in-channel work during the wet season, isolating work areas from flowing water, and others. This measure also requires that the creek banks and channel be restored to the original conditions and grade to mimic pre-project conditions. With these measures, the postproject creek conditions would be similar to existing conditions, and a cumulative or permanent impact to steelhead or steelhead habitat would not occur. Mitigation Measure BIO-1b requires that pre-construction nesting bird surveys be conducted, and appropriate no-work buffers be implemented if active nests are found. With this measure, the project would not result in a significant cumulative impact to nesting birds or their habitat. Mitigation Measure BIO-2a would ensure that temporary impacts to riparian woodland habitat during construction would not threaten the survival of riparian woodland habitat in the project site, thus resulting in a permanent impact to riparian woodland habitat. Mitigation Measure BIO-3 would include measures to avoid or minimize potential impacts to creek habitat resulting from the use of mechanical equipment in the creek bed. Consultation with appropriate regulatory agencies would occur for permanent impacts to the creek, and the project would implement all agreed upon mitigation measures. Therefore, the project would not result in a significant cumulative impact to biological or hydrological resources.
There are no known archaeological or paleontological resources within the project site, and the project would implement Mitigation Measures CUL-1, CUL-2, and GEO-1 to ensure that the project would not have a significant impact on unknown archaeological resources, paleontological resources, or human remains. Potential impacts to cultural resources and paleontological resources are site-specific and would not contribute to a cumulatively considerable impact.
The project has the potential to result in soil erosion which could result in loss of topsoil or siltation of nearby waterways. Mitigation Measures BIO-3 and HYDRO-1 would be implemented to reduce potentially significant impacts to a less-than-significant level. These measures include BMPs such as silt fencing, jute mesh, straw wattles, compliance with the RWQCB’s Erosion and Sediment Control Field Manual, and post construction erosion monitoring. All disturbed areas would be restored to their original grade and revegetated, which would prevent excessive erosion post-construction. Because measures would be implemented to ensure that erosion does not occur from post-project conditions, the project would not contribute to a cumulatively considerable erosion impact.
During construction, the project would require temporary closures of Creek Road. Mitigation Measure TRANS-1 which requires controls for traffic delays that may occur throughout construction. This measure would also ensure that adequate emergency access is provided throughout the project area during construction. The Town’s paving program plans repaving work on Bolinas Road during Fiscal Year 2028-2029 from Broadway to Deer Park Villa, which is in proximity to the Creek Road Bridge. Creek Road is also planned for repaving in Fiscal Year 2028- 2029 from Blackberry Lane to Bolinas Road. The Town, as manager of each of these projects as well as the proposed project, would ensure that work is appropriately staggered so that access is maintained for residents throughout the periods when these projects are active. There are no other projects planned within the immediate vicinity of the project site which would contribute to a cumulatively considerable transportation impact due to project construction. Once construction work on-site is finished, the transportation conditions would remain the same as existing Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 102
conditions. Therefore, the project would not contribute to a cumulatively considerable impact related to transportation or emergency access.
Construction work would generate noise during working hours, which is a temporary impact. The project would implement Mitigation Measure NOISE-1 to minimize noise from the project site to the maximum extent possible. Once construction is complete, noise conditions around the project site would be the same as existing conditions. Therefore, the project would not contribute to a cumulatively considerable noise impact.
Given that the project does not result in any significant impacts that cannot be mitigated to less-than-significant levels, the temporary nature of construction related impacts, and compliance with all regulations adopted to protect the environment, the proposed project would not result in impacts that are cumulatively considerable. c) Does the project have environmental effects that will cause substantial adverse effects on human beings, either directly or indirectly?
Less-than-Significant Impact with Mitigation Incorporated The project, particularly during the construction phase, could result in a variety of temporary impacts to human beings. The project’s construction phase would result in potentially significant impacts related to air quality, biological resources, cultural resources, geology and soils, hazardous materials, hydrology and water quality, noise, traffic, and tribal cultural resources; however, all impacts can be mitigated to less-than-significant levels via the mitigation measures included in this Initial Study/Proposed Mitigated Negative Declaration.
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 103
5.0 RESPONSE TO COMMENTS
The Draft IS/MND for the proposed Creek Road Rehabilitation Project (State Clearinghouse No. 2026050223) was circulated for a 30-day public review period from May 7, 2026, to June 8, 2026, pursuant to Section 15105 of the CEQA Guidelines.
The Draft IS/MND and the response to comments on the Draft IS/MND are informational documents prepared by the Lead Agency that must be considered by decisionmakers before approving the proposed project and that must reflect the Lead Agency’s independent judgment and analysis (CEQA Guidelines, Section 15090). This section usually responds to the comments and questions on the Draft IS/MND circulated by the Town to public agencies and the public as required by CEQA. However, no comments were submitted on the Draft IS/MND; therefore, this Final IS/MND does not include responses to comments submitted by public agencies or the public. This Final IS/MND does not describe the Project having any new or substantially more severe impacts than those identified and analyzed in the Draft IS/MND. Therefore, in accordance with CEQA Guidelines Section 15073.5, recirculation of the Draft IS/MND is not required.
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6.0 MITIGATION MONITORING AND REPORTING PROGRAM
CEQA Guidelines (California Code of Regulations, Title 14), Section 15097, requires public agencies to adopt reporting or monitoring programs when they approve projects to an Environmental Impact Report or negative declaration that includes mitigation measures to avoid significant environmental effects. The reporting or monitoring program shall be designed to ensure compliance with conditions of project approval during project implementation in order to avoid significant adverse environmental effects.
This Mitigation Monitoring and Reporting Program (MMRP) has been prepared pursuant to CEQA Guidelines Section 16097, which states the following:
In order to ensure that the mitigation measures and project revisions identified in the EIR or negative declaration are implemented, the public agency shall adopt a program for monitoring or reporting on the revisions which it has required in the project and the measures it has imposed to mitigate or avoid significant environmental effects. A public agency may delegate reporting or monitoring responsibilities to another public agency or to a private entity which accepts the delegation; however, until mitigation measures have been completed the lead agency remains responsible for ensuring that implementation of the mitigation measures occurs in accordance with the program.
The public agency may choose whether its program will monitor mitigation, report on mitigation, or both. “Reporting” generally consists of a written compliance review that is presented to the decision-making body or authorized staff person. A report may be required at various stages during project implementation or upon completion of the mitigation measure. "Monitoring" is generally an ongoing or periodic process of project oversight. There is often no clear distinction between monitoring and reporting and the program best suited to ensuring compliance in any given instance will usually involve elements of both.
The basis for this MMRP are the mitigation measures included in the Final IS/MND (SCH 2026050223) prepared for the Creek Road Bridge Rehabilitation Project. These mitigation measures are designed to eliminate or reduce significant adverse environmental effects of the project to less-than-significant levels. The Town of Fairfax has agreed to implement the mitigation measures as required, before and during implementation of the proposed project.
Table 7 below presents the potentially significant impacts and proposed mitigation measures identified in the Final IS/MND, the timing of implementation of the mitigation measures (i.e., when the measure will be implemented), the Town staff or individual responsible for ensuring implementation of each mitigation measure, and the Town staff member or individual responsible for monitoring the mitigation measures.
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Table 7. Mitigation Monitoring and Reporting Program
MITIGATION MEASURES
IMPLEMENTATION
RESPONSIBILITY
IMPLEMENTATION
TIMING
COMPLIANCE RECORD
AIR QUALITY
Mitigation Measure AIR-1. Fugitive Dust Control Measures The Bay Area Air District (BAAD) recommends basic construction measures to ensure minimal impacts on regional air quality. The contractor shall be responsible for implementing the following basic measures:
• All exposed surfaces (e.g., parking areas, staging areas, soil piles, graded areas) shall be watered two times per day, as appropriate; pave, apply water three times
daily, or apply (non-toxic) soil stabilizers on all
unpaved access roads, parking area and staging areas.
• All paved access roads, parking areas and staging
areas at the construction site shall be swept daily with water sweepers. All visible mud or dirt track-out onto
adjacent public roads shall be removed using wet
power vacuum street sweepers at least once per day.
The use of dry power sweeping is prohibited.
• Idling times shall be minimized either by shutting
equipment off when not in use or reducing the
maximum idling time to 5 minutes (as required by the
California airborne toxics control measure Title 13,
Section 2485 of California Code of Regulations). Clear
signage shall be provided for construction workers at
all access points.
• All construction equipment shall be maintained and
properly tuned in accordance with manufacturer‘s
specifications, and all equipment shall be checked by a certified visible emissions evaluator.
• A publicly visible sign with the telephone number and person to contact at the lead agency regarding dust
complaints shall be posted in or near the project area.
The contact person shall respond to complaints and
take corrective action within 48 hours. The BAAD’s
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
For duration of
construction
Initials ____________
Date ______________
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phone number shall also be visible to ensure
compliance with applicable regulations.
BIOLOGICAL RESOURCES
Mitigation Measure BIO-1a. Steelhead and Essential Fish Habitat (EFH)
Habitat within the project site is critical habitat for both Coho salmon and steelhead. As mentioned above, while Coho salmon are considered extirpated, steelhead are considered present. In addition to the measures identified for the Perennial Stream Biological Community; the following measures shall be implemented to avoid and minimize potential project impacts to steelhead, critical habitat for steelhead, and EFH.
• Consultation with National Marine Fisheries Service
(NMFS) shall be conducted to ensure project design
would not result in a permanent adverse effect to
steelhead or critical habitat.
• Work within the channel shall be conducted during the dry season (June 1 through October 31) to avoid
disrupting the adult migration cycle. Work outside of
this period shall require consultation with NMFS.
• Work should be conducted in isolation from flowing
water. Prior to the start of construction activities, the work area should be isolated, and flowing water should
be diverted around the isolated area.
• A fish salvage plan shall be developed prior to the
onset of any in-water work. The plan shall be
implemented by a qualified biologist during dewatering
activities in San Anselmo Creek. The fish salvage plan
shall include an overview of the proposed methods for
dewatering, expected location and duration of
dewatering activities, and methods for conducting fish
salvage during dewatering activities.
• Prior to construction, the contractor shall be required to prepare an Accidental Spill Prevention and Cleanup
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
During project design,
prior to, for duration of,
and following
completion of
construction
Initials ____________
Date ______________
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Plan. This plan shall include required spill control
absorption material, for use beneath stationary
equipment, to be present on-site and available at all
times.
• Silt fencing or other approved sediment trapping shall be installed down gradient of the work site to minimize off-site transport of sediments.
• All stockpiling of construction materials, equipment, and supplies, including storage of chemicals, refueling and maintenance, shall occur outside the creek channel.
No equipment would be washed where runoff could
enter the creek.
• No motorized equipment shall be left within the channel (top of bank to top of bank) overnight unless a
container or similar method is securely placed beneath
the equipment to catch any fluid leakage. All contained fluids shall be disposed of in a permitted manner.
• The contractor shall be required to use a drilling mud and slurry seal that is nontoxic to aquatic life if there are drilling activities related to construction of the
proposed project. All drilling muds and fluid shall be
contained on-site in tanks and disposed of in a
permitted manner. Fluids from saw cutting and other
activities shall be collected and not allowed to flow
into the creek.
• The creek banks shall be restored to pre-project
conditions following the completion of work.
The creek channel shall be restored to the original grade using native cobble, gravel, and soils in appropriate ratios to mimic preproject conditions.
Mitigation Measure BIO-1b. Nesting Birds and Avian Species Although potential nesting habitat for breeding birds would not be lost as a result of the project, construction could disturb active nests. The following measures shall be implemented to avoid and Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
Prior to and for duration
of construction
Initials ____________
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minimize potential impacts to special-status, and non-specialstatus nesting bird species:
• If project activities begin between February 15 and
August 31, pre-construction surveys shall be conducted
by a qualified biologist prior to ground disturbance to determine whether active nests containing eggs, chicks, or young are present beneath the bridge and in the
surrounding riparian area. Pre-construction surveys for active nests shall be conducted no more than 14 days
prior to ground disturbing activities.
• If active nests containing eggs, chicks, or young are not observed during pre-construction surveys, construction
can proceed.
• If active nests containing eggs, chicks, or young are observed, a qualified biologist shall establish an
exclusion zone of 25-100 feet for passerine birds and
200-500 feet for raptors, depending on the species.
Appropriate exclusion distances shall be determined by
a qualified biologist based on the species present and
location of the nest relative to construction activities (e.g., the nest is sufficiently shielded from construction to avoid disturbance). The exclusion zone shall be
marked with high visibility fencing and monitored
weekly to ensure no encroachment. Ground-disturbing
activities within these zones shall be prohibited until the qualified biologist confirms that the nests are no
longer active. If an active nest is found after the
completion of the pre-construction surveys or after
construction begins, all construction activities shall stop until a qualified biologist has evaluated the nest and
determined an appropriate buffer to be placed around
the nest. If avoidance of a buffer zone is not feasible, California Department of Fish and Wildlife (CDFW) shall be contacted to coordinate an appropriate course of
action.
Date ______________
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Mitigation Measure BIO-2a. Riparian Woodland
The following avoidance and minimization measures shall be employed to avoid or minimize impacts to riparian woodland:
• Temporarily impacted areas in this habitat shall be
revegetated with native, non-invasive plants suitable
for the soil and site conditions.
• Silt fencing or other approved sediment trapping shall be installed down gradient of the work site to minimize off-site transport of sediments.
• Exclusion fencing shall be installed along the limits of clearing and grubbing to prevent encroachment into
undisturbed habitats.
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
Prior to and for duration
of construction
Initials ____________
Date ______________
Mitigation Measure BIO-3. Perennial Stream and Wetlands: Creek Habitats
The following measures are included to avoid and/or minimize and restore potential impacts to creek habitat resulting from the use of mechanical equipment in the creek bed.
• The construction contractor shall ensure all in-stream construction work is completed during the dry season,
between April 15 and October 15. Work outside of this
period shall require written approval from the California Department of Fish and Wildlife (CDFW) and Regional
Water Quality Control Board (RWQCB), and any
additional mitigation measures prescribed shall be
implemented.
• Final grading in the creek bed shall conform to the
existing creek channel both downstream and upstream,
and existing bed materials shall be replaced with
similar sized materials.
• Regulatory approval shall be obtained for all work
within potentially jurisdictional areas, including
approval from the United States Army Corps of
Engineers (Corps), RWQCB, CDFW, and NMFS. All work
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
Prior to, for duration of,
and following
completion of
construction
Initials ____________
Date ______________
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within these areas shall conform to any conditions
imposed by the regulating agencies.
• Prior to any clearing, grubbing, pruning, or
groundbreaking activity, the limits of construction shall be fenced with temporary high-visibility construction
fencing to protect environmentally sensitive areas,
including all riparian or wetland vegetation and prevent any equipment from unnecessarily extending the work
area or entering the wetted channel. In addition, silt
fencing shall be installed at the base of the
construction fencing to prevent debris from entering the creek. All fencing shall be removed upon project
completion.
• Prior to construction, the contractor shall be required to prepare an Accidental Spill Prevention and Cleanup
Plan. This plan shall include required spill control
absorbent material, for use beneath stationary
equipment, to be present on-site and available at all
times.
• To minimize fluid leaks during operation, refueling, and maintenance of stationary equipment spill control
absorbent material shall be in place underneath this
equipment at all times to capture potential leaks. All
refueling and maintenance of equipment, other than
stationary equipment, shall occur outside the creek’s
top-of-bank. Any hazardous chemical spills shall be
cleaned immediately.
• All stockpiling of construction materials, equipment, and supplies, including storage of chemicals, refueling and maintenance, shall occur outside the creek channel.
No equipment shall be washed where runoff could enter
the creek.
• No motorized equipment is to be left within the channel (top of bank to top of bank) overnight unless a
container or similar method is securely placed beneath
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the equipment to catch any fluid leakage. All contained fluids shall be disposed of in a permitted manner.
• The contractor shall be required to use a drilling mud and slurry seal that is nontoxic to aquatic life if there are drilling activities related to construction of project.
All drilling muds and fluid shall be contained on-site in tanks and disposed of in a permitted manner. Fluids
from saw cutting and other activities shall be collected and not allowed to flow into the creek.
• No equipment, including concrete trucks, shall be
washed within the channel of the creek, or where wash
water could flow into the channel. Prior to project
construction, the contractor shall establish a concrete washout area for concrete trucks in a location where
wash water shall not enter the creek or adjacent areas.
The washout area shall follow the practices outlined in the San Francisco Bay Regional Water Quality Control
Board Erosion and Sediment Control Field Manual
(page 107-108, July 1999) or equivalent guidelines.
Substitution of the designated concrete washout area
or methods shall require prior approval of the Town of
Fairfax.
• All water that comes in contact with wet concrete must be pumped directly into tanks and disposed of at a
permitted location.
• If work is to occur on the roadway and bridge
approaches during the period October 15 to June 15, all drainage inlets within the project site shall be protected from receiving polluted storm water through the use of
filters such as fabrics, gravel bags, straw wattles, or other appropriate BMPs.
• Water encountered during construction of the bridge
foundations shall be managed in accordance with an
approved dewatering plan.
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• All workers shall ensure that food scraps, paper
wrappers, food containers, cans, bottles, and other
trash from the project site are deposited in covered or closed trash containers. The trash containers shall not be left open and unattended overnight.
• The Town of Fairfax shall require that all disturbed
areas around the bridge bents and abutments be regraded to match the surrounding topography by October 15. Seed and certified weed-free straw shall be placed on disturbed areas in the project site (with the exception of the lower creek banks, creek bed, and
areas below the ordinary high water mark [OHWM]). A
jute mesh type or equivalent matting shall be placed
over the straw, installed per the manufacturer’s
instructions. This matting shall have no plastic
incorporated into it. Substitution of materials or erosion control methods shall require prior approval of the
Town of Fairfax.
• After construction, the project site shall be inspected following the first heavy rain, during the middle of the rainy season and at the end of the rainy season. During each visit areas of significant erosion or erosion control device failure shall be noted and appropriate remedial
actions taken.
CULTURAL RESOURCES
Mitigation Measure CUL-1. Unknown Archaeological Resources If any archaeological deposits are encountered, the construction contractor shall immediately halt all soil-disturbing work within 25 feet of the discovery. A qualified archaeologist shall assess the significance of the find(s) and prepare a recommendation for further action. If the archaeological materials are determined to be significant, a qualified cultural resources professional shall develop an appropriate treatment plan in consultation with the Town. The plan could include avoidance and preservation measures to Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
For duration of
construction
Initials ____________
Date ______________
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preserve the materials in place; scientific collection and analysis; preparation of a professional report in accordance with current professional standards; and professional museum curation of collected cultural materials and resource documentation. Soildisturbing work within the area of the find shall not resume until a treatment plan has been approved by the Town of Fairfax.
Mitigation Measure CUL-2. Human Remains
In the event of post-review discoveries of human remains, the project shall implement the following procedures:
• The treatment of human remains and of associated or
unassociated funerary objects discovered during any
soil-disturbing activity within the project shall comply with applicable State laws. Pursuant to Section 7050.5
of the Health and Safety Code, and PRC Section
5097.94, in the event of the discovery of human
remains during construction, there shall be no further
excavation or disturbance of the site or any nearby
area reasonably suspected to overlie adjacent remains.
The Marin County Coroner shall be immediately notified
and shall make a determination as to whether the
remains are Native American.
• In the event of the coroner's determination that the
human remains are Native American, notification of the
Native American Heritage Commission (NAHC), is
required who shall appoint a Most Likely Descendant
(MLD) (PRC Section 5097.98). The archaeological
consultant, project sponsor, and MLD shall make all
reasonable efforts to develop an agreement for the
treatment, with appropriate dignity, of human remains
and associated or unassociated funerary objects (CEQA
Guidelines Section 15064.5(d)). The agreement should
take into consideration the appropriate excavation,
removal, recordation, analysis, custodianship, curation, and final disposition of the human remains and
associated or unassociated funerary objects. California Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
For duration of
construction
Initials ____________
Date ______________
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Public Resources Code allows 48 hours to reach
agreement on these matters. If the MLD and the other
parties do not agree on the reburial method, the project shall follow PRC Section 5097.98(b) which states that
"the landowner or his or her authorized representative
shall reinter the human remains and items associated
with Native American burials with appropriate dignity
on the property in a location not subject to further
subsurface disturbance."
GEOLOGY AND SOILS
Mitigation Measure GEO-1. Paleontological Resources
In the event of post-review discoveries of paleontological resources the following recommendations apply:
• If any paleontological deposits or unique geological
resources are encountered, all soil-disturbing work shall be halted at the location of any discovery until a
qualified paleontologist or geologist evaluates the
significance of the find(s) and prepares a
recommendation for further action. If the materials are determined to be significant, a qualified professional
shall develop an appropriate treatment plan in
consultation with the Town and the Environmental
Protection Agency (EPA) to mitigate the discovery. The
plan could include avoidance and preservation
measures to preserve the materials in place; scientific collection and analysis; preparation of a professional
report in accordance with current professional
standards; and, professional museum curation of
collected materials and resource documentation.
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
For duration of
construction
Initials ____________
Date ______________
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HYDROLOGY AND WATER QUALITY
Mitigation Measure HYDRO-1. NPDES Permit
The contractor shall prepare a Stormwater Pollution Prevention Plan (SWPPP) in accordance with the National Pollutant Discharge Elimination System(NPDES) General Construction Permit, pursuant to the Clean Water Act (CWA). Best Management Practices shall be identified in the SWPPP to reduce or eliminate pollutants from the construction site entering storm water discharges. Implementation of BMPs shall control erosion and to ensure that dirt, construction materials, pollutants, or other human-associated materials are not discharged from the project area into surface waters or into areas that would eventually drain to storm drain systems. BMPs required by the SWPPP may include but are not limited to silt fencing, erosion control blankets, and street sweeping.
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
Prior to and for duration
of construction
Initials ____________
Date ______________
Mitigation Measure HYDRO-2. Water Quality Standards
The Town of Fairfax shall require the construction contractor to submit an equipment staging plan and proposed staging locations no later than 30 days prior to the start of construction. The specifications shall include at minimum, the following requirements:
• The staging area shall be located on an existing
asphalt or concrete surface area. No staging shall be
permitted on undeveloped lots. The Contractor shall
notify the Town whether or not a suitable area is
available.
• The staging area shall be included in the Contractor’s Water Quality Protection Plan.
• The staging area shall not be located in an
environmentally or culturally sensitive area and /or
impact water resources (rivers, streams, bays, inlet,
lakes, drainage sloughs).
• The staging area shall not be located in a regulatory floodway within the base floodplain (100-year).
• The staging area shall be inspected weekly by the
project environmental monitor to ensure compliance
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
Prior to and for duration
of construction
Initials ____________
Date ______________
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with the Water Quality Protection Plan, and any
violations will result in immediate suspension of the
work until rectified.
NOISE
Mitigation Measure NOI-1. Construction Noise
In order to comply with Policy N-3.1.4, the Town of Fairfax has developed a list of Standard Controls. The project shall comply with the following measures:
1. Limit construction to the hours of 8:00 a.m. to 5:00 p.m. on weekdays, and 9:00 a.m. to 5:00 p.m. on Saturdays, with no noise-generating construction on Sundays or Holidays.
2. Control Noise from construction workers’ radios to the point where they are not audible at existing residences that
border the project site.
3. Equip all internal combustion engine-driven equipment with mufflers which are in good condition and appropriate for the equipment.
4. Utilize quite models of air compressors and other stationary noise sources where technology exists.
5. Locate stationary noise-generating equipment as far as possible from sensitive receptors when sensitive receptors adjoin or are near a construction project area.
6. Prohibit unnecessary idling of internal combustion engines.
7. Notify residents adjacent to the project site of the construction schedule in writing.
8. Designate a noise disturbance coordinator who would be responsible for responding to any local complaints about construction noise. The disturbance coordinator would
determine the cause of the noise complaints (e.g., starting too early, bad mufflers) and institute reasonable measure warranted to correct the problem. Conspicuously post a
telephone number for the disturbance coordinator at the construction site.
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
Prior to and for duration
of construction
Initials ____________
Date ______________
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In addition, the project shall follow the standard construction noise requirements regulated by Caltrans Sections 7-1.01I and 14-8.02 of the Standard Specifications which states the following:
1. Do not exceed 86 dBA at 50 feet from the job site activities from 9 p.m. to 6 a.m.
2. Equip an internal combustion engine with the
manufacturer-recommended muffler. Do not operate an
internal combustion engine on the job site without the
appropriate muffler.
TRANSPORTATION
Mitigation Measure TRANS-1. Traffic Control Plan
Prior to construction activities at the project site, a traffic control plan shall be prepared for implementation throughout project construction. The traffic control plan shall be subject to review and approval by the Town prior to implementation. The traffic control plan shall contain the provisions such as the following:
1. At least one week prior to the commencement of
construction work, the Town shall require the
contractor to provide project information signs to
notify drivers of the upcoming project and potential
delays.
2. Lane closure and traffic control during project
construction will conform to the California Manual
on Uniform Traffic Control Devices (CAMUTCD),
Caltrans standard plans and specifications.
3. The contractor will install advance warning signs to alert bicyclists and motorists of the construction
work zone and lane closures. Advance warning
signs may be reflective signs, changeable message
boards, cones, and barricades. All temporary
signage related to construction work shall be
removed by the construction contractor after
project construction work has finished.
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
Prior to construction
Initials ____________
Date ______________
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4. Flagging and other means of traffic control will be
required to allow for the safe movement of traffic
through the work zone. The contractor will provide
flaggers to temporarily hold traffic for staging
equipment or construction.
5. Work shall be performed in a manner that is least
disruptive to the public. The contractor will consult
and coordinate with the property owner if access
will be affected.
6. The Town shall coordinate with local emergency
services (i.e., the police and fire departments) to
inform them of temporary construction work and
potential road closures. Emergency access shall be
maintained throughout the project duration.
With implementation of a traffic control plan and the temporary nature of construction-related traffic, impacts on traffic would be less than significant.
TRIBAL CULTURAL RESOURCES
Mitigation Measure TCR-1. Outreach to the Federated Indians Graton Rancheria
The Town of Fairfax shall reach out to Graton Rancheria no less than 30 days prior to construction to confirm whether they would like to have a tribal monitor present during excavation activities. If requested by Graton Rancheria, the Town shall arrange to have a tribal monitor present during excavation work.
Implementation
Responsibility: Town of
Fairfax
Implementation Timing:
Prior to construction
Initials ____________
Date ______________
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7.0 REFERENCES
Altman, B., and R. Sallabanks. 2000. Olive-sided Flycatcher (Contopus cooperi). In The Birds of North America, No. 502 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
Association of Bay Area Governments (ABAG) 2020. MTC/ABAG Hazard Viewer Map. https://mtc.maps.arcgis.com/apps/webappviewer/index.html?id=4a6f3f1259df42eab29b35dfcd08 6fc8. Accessed October 2025.
Bay Area Air District (BAAD). 2017. Spare the Air, Cool the Climate. Final 2017 Clean Air Plan. https://www.baaqmd.gov/~/media/files/planning-and-research/plans/2017-clean-airplan/attachment-a_-proposed-final-cap-vol-1-pdf.pdf. Accessed October 2025.
Bay Area Air District (BAAD). 2022. 2022 CEQA Guidelines. https://www.baaqmd.gov/plans-andclimate/california-environmental-quality-act-ceqa/updated-ceqa-guidelines. Accessed October 2025.
California Department of Conservation (CDOC). 2016. Mines Online. https://maps.conservation.ca.gov/mol/index.html. Accessed October 2025.
California Department of Conservation (CDOC). 2022a. California Important Farmland Finder. https://maps.conservation.ca.gov/DLRP/CIFF/. Accessed October 2025.
California Department of Conservation (CDOC). 2022b. Williamson Act Enrollment Finder. https://maps.conservation.ca.gov/dlrp/WilliamsonAct/. Accessed October 2025.
California Department of Fish and Game (CDFG). 1994. A Field Guide to Lake and Streambed Alteration Agreements, Sections 1600-1607. Environmental Services Division, California Department of Fish and Wildlife, Sacramento, California.
California Department of Fish and Wildlife. 2026.
California Department of Forestry and Fire Protection (CAL FIRE). 2025. Fire Hazard Severity Zone Viewer for Real Estate Inspections.
https://experience.arcgis.com/experience/03beab8511814e79a0e4eabf0d3e7247/. Accessed October 2025.
California Department of Transportation (Caltrans). 2013a. Technical Noise Supplement (TeNS) to the Traffic Nosie Analysis Protocol. https://dot.ca.gov/-/media/dotmedia/programs/environmental-analysis/documents/env/tens-sep2013-a11y.pdf. Accessed October 2025.
California Department of Transportation (Caltrans). 2013b. Transportation and Construction Vibration Guidance Manual. https://www.placer.ca.gov/DocumentCenter/View/8273/Caltrans2013-Transportation-and-Construction-Vibration-Guidance-Manual-Archive-PDF?bidId=.
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Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 Appendix A
APPENDIX A. NATURAL ENVIRONMENT STUDY
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 Appendix B
APPENDIX B. BIOLOGICAL ASSESSMENT
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 Appendix C
APPENDIX C. NOISE STUDY
Creek Road Bridge Rehabilitation Project · Town of Fairfax Final Initial Study/Mitigated Negative Declaration | June 2026 Appendix D
APPENDIX D. CULTURAL RESOURCES REPORTS
Under separate cover and available for review at the Town of Fairfax.