Thomas R. Boag Kati Aho Janet Lundgren
September 28, 2026 Received
City Clerk, City of Sebastopol SEP 29 2026
Attn: Mary Gourley, CMC, City Clerk / City Manager City of Sebastopol 7120 Bodega Avenue
Admin Services - Finance
Sebastopol, CA 95472
Re: Appeal of Planning Commission Action of September 22, 2026 — 8100 Valentine Avenue "Valentine Avenue Homes" (File No. 2025-067)
STATEMENT OF GROUNDS FOR APPEAL
To the City Clerk and City Council:
Pursuant to Sebastopol Municipal Code Chapter 17.455, I hereby appeal the September 22, 2026, action(s) of the Planning Commission on the above-referenced project. This statement is submitted together with the City's signed Appeal Form and the applicable appeal fee, within seven calendar days of the Commission's action, as required by SMC 17.455.020(D).
1. Scope of Appeal
I appeal each of the following actions taken or relied upon by the Planning Commission on September 22, 2026, to the extent each constitutes a final Commission decision or a determination incorporated into its recommendation to the City Council:
• The determination that the project is exempt from further environmental review under CEQA Guidelines Section 15183 (Public Resources Code Section 21083.3). • Any approval of, or finding supporting, a Tree Removal Permit or tree-related determination under Sebastopol Municipal Code Chapter 8.12.
• Any Design Review approval for the project; and
• The recommendation to the City Council regarding the Vesting Tentative Map, Density Bonus concessions, and associated waivers, to the extent that recommendation incorporates or relies on the CEQA determination or the tree and design findings identified above.
This appeal is filed protectively as to all of the above because the record does not make clear which of these actions the Commission treated as final and which as recommendatory, and I want to ensure the City Council is not foreclosed from reviewing any of them.
I understand City staff have raised a question whether some or all of the Planning Commission's September 22, 2026, action is a "recommendation" to the City Council rather than a final, independently appealable "decision" under SMC Chapter 17.455, given that the Commission's resolution recommends findings and action to the City Council rather than stating that the Commission itself approves them. I do not concede that no appeal right exists. The City's own September 22, 2026, agenda for this meeting states without qualification: "Appeals may be filed of official actions upon filing of an appeal form and payment of the applicable appeal fee. Such appeals, including the appeal fee, must be filed within 7 days of the action. Appeals will be heard by the City Council." To avoid forfeiting any appeal right that does exist, I am filing this appeal within that stated seven-day period. If the City Attorney determines that no formal appeal under Chapter 17.455 is procedurally required or applicable to some or all of the items listed above, I ask that this filing instead be treated as, and given the effect of, a timely written request that the City Council independently and fully consider each of the grounds set out below as part of its own hearing on the Vesting Tentative Map and related entitlements, and that the appeal fee be refunded in full, consistent with the City's adopted Schedule of User and Regulatory Fees, which provides for a 100% refund when the Planning director determines that a fee is not required by the Municipal Code.
2. Grounds for Appeal
A. The CEQA Section 15183 exemption determination rests on an incorrect and outdated environmental record.
The City's own Arborist review (Exhibit D, dated July 21, 2026) [COPY ATTACHED 1] found that the applicant's tree inventory applied the wrong protected-tree threshold for this R-4 zoned property, and that the correct application increases the protected-tree count from 18 to 23 and the proposed removals from 7 to 11. CEQA Guidelines Section 15183(b) requires an agency relying on this exemption to examine effects that are "peculiar to the project or the parcel" or that, based on new information, "are determined to have a more severe adverse impact than discussed in the prior EIR." I am not aware that the Section 15183 checklist or supporting analysis has been revised to reflect the Arborist's corrected findings before the Commission acted.
B. The application lacks a Tree Protection Plan required for work within the dripline of protected trees, and no documented final action has been taken by the Design Review Board/Tree Board on the corrected tree removal permit.
The Design Review Board, sitting as the City's Tree Board under SMC Chapter 8.12, is a body with authority over tree matters that is legally distinct from the Planning Commission. The March 17, 2026, joint session predated the Arborist's corrected tree counts by four months, and the project did not appear on the Tree Board's regular September 22, 2026, agenda. I have found no published minutes, resolution, or vote reflecting Tree Board action on this project using the corrected data.
Separately, Sebastopol Municipal Code Section 8.12.050 requires a Tree Protection Plan (TPP), prepared by an ISA-certified arborist, as part of any application affecting protected trees where proposed work is located within the dripline of those trees. The City's own tree review (Exhibit D) confirms that this project requires a TPP under Section 8.12.050 because work is proposed within the driplines of protected trees, including significant root-zone impacts to the northeast redwood grove. The code further requires that "construction of walls, foundations, buildings, and grading shall be minimal within the dripline of affected trees, ," and that trees designated to be preserved be enclosed in approved protective fencing before any grading, equipment movement, or other construction activity begins. The site plan shows Building 25 positioned over a protected 34-inch redwood, with additional retained trees close to the footprints of Buildings 24, 27, and 28. I have found no Tree Protection Plan in the public record, and the draft Conditions of Approval defer "Tree Protection Measures" to City Arborist review before Final Map recordation rather than requiring the plan, fencing specifications, and dripline analysis as part of the application, as Section 8.12.050 requires.
C. Emergency vehicle access adequacy has not been confirmed in writing by the Fire Code Official.
The City's own traffic consultant, W-Trans, found in its focused transportation study [COPY ATTACHED 21 that the proposed 12-foot secondary emergency access route "would be inadequate to accommodate passage by fire trucks," and recommended either a looped connection to Valentine Avenue or widening to at least 24 feet. The draft Conditions of Approval confirm that Fire Code Official approval of a Fire Apparatus Access Plan has not yet occurred and is deferred to a later stage. I understand staff represented at the September 22 hearing that the Fire Marshal had approved the project's access; I do not believe that representation is supported by a written determination in the record.
D. Sebastopol Municipal Code Section 16.40.040 Circulation [COPY ATTACHED 3] has not been addressed in writing.
SMC 16.40.040 requires multiple access for subdivisions with streets exceeding 500 feet. W- Trans measured the project's internal drive aisle at approximately 545 feet. I have found no written determination in the record addressing this threshold.
E. Compliance with the California Fire Code's two-access-road requirement for developments over 30 dwelling units has not been addressed in writing.
Sebastopol Municipal Code Section 15.04.120 [COPY ATTACHED 4] adopts the California Fire Code, including Appendix D (Fire Apparatus Access Roads). Appendix D Section D107.1, [COPY ATTACHED 5] as published in the adopted model code, provides that developments of one- or two-family dwellings where the number of dwelling units exceeds 30 shall be provided with two separate and approved fire apparatus access roads. This project proposes 39 total dwelling units (20 single-family lots plus 19 accessory dwelling units), which exceeds that threshold. I have found no local amendment to this dwelling-unit number and no written determination in the record addressing whether Section D107.1 applies to this project or how the project's single primary entrance and 12-foot secondary emergency route would satisfy it if it does.
3. Relief Requested
1. That the City Council review the CEQA Section 15183 determination, the Tree Removal Permit, and the Design Review approval as part of its consideration of this project, rather than treating any of them as final and unreviewable.
2. That staff be directed to confirm in writing whether the corrected tree data requires the CEQA checklist to be revised, and to place that confirmation in the record before any further action.
3. That the Design Review Board/Tree Board review and act on the tree removal permit using corrected tree counts before the City Council's final action.
4. That a Tree Protection Plan meeting the requirements of Sebastopol Municipal Code Section 8.12.050 — including protective fencing, defined tree protection zones, and a specific accounting of how each retained tree's dripline, including the 34-inch redwood associated with Building 25, will be protected from building, foundation, and grading encroachment - be prepared, reviewed by the Tree Board, and placed in the record before the City Council's final action.
5. That a written determination from the Fire Code Official confirming (or specifying what is needed to confirm) the adequacy of emergency vehicle access be placed in the record before the City Council's final action.
6. That a written finding on Sebastopol Municipal Code Section 16.40.040 be placed in the record before the City Council's final action; and
7. That a written determination be placed in the record confirming whether California Fire Code Appendix D Section D107.1 (two fire apparatus access roads for developments exceeding 30 dwelling units) applies to the project, and if so, how the project satisfies it, before the City Council's final action.
4. Reservation of Rights
This appeal is filed to preserve my right to a City Council hearing on the items above within the time allowed. I reserve the right to supplement these grounds with additional detail, documentation, and legal authority before the Council hearing on this appeal, and to raise related issues supported by the administrative record.
Please confirm receipt of this appeal and advise of the hearing date and any additional procedural requirements.
Urban Forestry Associates July 21, 2026
8100 Valentine Avenue Development Tree Review
Client: City of Sebastopol, Community Development Department Project Location: 8100 Valentine Avenue, Sebastopol, CA Inspection Date: July 21, 2026
Arborist: Ben Anderson
URBAN FORESTRY_ ASSOCIATES, INC.
Summary
The 8100 Valentine Avenue site supports a mix of native and ornamental trees in generally fair to good condition, including a stand of mature coast redwoods (Sequoia sempervirens) in the northeast corner and several protected native oaks. The materials submitted for the development function as a basic tree inventory, but they do not yet meet the tree protection plan requirements that this project triggers under the Sebastopol Municipal Code. The inventory does not include a protection plan sheet a contractor can follow, the field tagging could not be verified, at least one protected tree is misidentified, and replacement and protection measures are described only in general terms. The inventory also applies the protected-tree threshold for single-family and duplex properties, which understates the number of protected trees on this parcel and the mitigation their removal requires.
Before a meaningful protection review can be completed, the applicant must correct these items and submit a tree protection plan, including a plan sheet, prepared by the project arborist. I also recommend that Tree 52 be reclassified as a removal or that the site plan be modified to give it a survivable growing space.
Assignment
John Jay, contract associate planner with the City of Sebastopol Community Development Department, asked me to review the tree-related materials submitted for the proposed residential development at 8100 Valentine Avenue and to provide comments for the City's conditions of approval. The materials I reviewed are the Tree Inventory Report prepared by John C. Meserve of Horticultural Associates dated December 5, 2025, the applicant's written project description dated December 18, 2025 and updated May 21, 2026, and the tentative map. The project is a 20-lot, 39-home residential subdivision on the former Church of Jesus Christ of Latter- day Saints parcel, Assessor's Parcel Number 008-510-054.
I inspected the site on July 21, 2026 and walked the tree locations. I did not conduct an independent tree-by- tree inventory or a formal tree risk assessment, and my comments rely on Meserve's inventory data except where my field observations differ. This review is limited to the adequacy of the submitted tree materials and to the tree protection and removal issues raised by the proposed development.
Observations
The site is the former church property. Trees are concentrated along the perimeter and in the northeast corner, and the inventory documents 46 trees. The dominant trees are the coast redwoods in the northeast corner and a group of protected native oaks, including coast live oak (Quercus agrifolia), Oregon oak (Quercus garryana), and valley oak (Quercus lobata). The remaining trees are ornamental species, including flowering pear (Pyrus calleryana), crape myrtle (Lagerstroemia indica), London plane (Platanus x acerifolia), Chinese pistache (Pistacia chinensis), European birch (Betula sp.), flowering cherry (Prunus serrulata), Pacific wax myrtle (Morella californica), and Eastern redbud (Cercis canadensis).
The Tree Inventory Report states that each tree was identified in the field with a numbered aluminum tag placed at approximately eye level. During my inspection most of the trees did not have tags. Without reliable tags, or another unambiguous way to locate each numbered tree, a contractor cannot connect the report's recommendations to the trees on the ground.
Tree 52 is identified in the inventory as a valley oak. Based on my field inspection it is an Oregon oak. Its canopy is asymmetric and weighted over the footprint of Building 22.
Urban Forestry Associates July 21, 2026
8100 Valentine Avenue Development Tree Review
The coast redwoods in the northeast corner, including Tree 32, are close to proposed grading and structures and will experience significant root zone impacts during construction.
Several additional trees grow just outside the property lines on neighboring parcels. Their trunks are off site, but their root systems, and in some cases their canopies, extend onto the project site.
Discussion
Because this is a development project with work proposed within the driplines of protected trees, a tree protection plan prepared by an International Society of Arboriculture certified arborist is required as part of the application under Sebastopol Municipal Code 8.12.050. The code lists the information a tree protection plan must contain. It calls for the size, species, health, crown diameter, and trunk location of all trees whose dripline is within the development area, whether on the subject property or an adjoining property. It also calls for the measures proposed to ensure the survival of the trees to remain, the size, species, and location of replacement trees, the maintenance and irrigation program for those trees, the existing and proposed grading and drainage characteristics as they relate to trees, and the protective fencing, tree protection zones, and contractor responsibility notes to be shown on the plan sheets.
The submitted Tree Inventory Report provides tree size, species, health, structure, and a location plan, which partly satisfies the first requirement. It does not provide the survival measures, the tree protection zones and fencing locations, the grading and drainage detail, the replacement tree specifications and maintenance program, or the plan sheet notes that the remaining subsections require. The report is a basic inventory, not the tree protection plan the code calls for.
The applicable threshold for a protected native tree depends on the property type. Sebastopol Municipal Code
8.12.040 defines a protected native tree as a listed native species with a trunk diameter of at least 10 inches on all properties other than single-family or duplex residential properties, and at least 20 inches on single- family or duplex residential properties. Sebastopol Municipal Code 8.12.060(A) makes the same distinction for when a tree removal permit is required.
The Tree Inventory Report applies the 20-inch single-family and duplex threshold and identifies 18 protected native trees on that basis. This parcel is zoned R-4, Medium Density Residential, and currently houses a church, so it is not a single-family or duplex residential property. The 10-inch threshold applies, which brings additional native trees into the protected category and increases the mitigation associated with their removal.
Sebastopol Municipal Code 8.12.060(E) provides that any tree removal permit shall include a condition requiring replacement trees, an in-lieu fee, or an approved alternative, and that the mitigation must be related to the significance, meaning the size and age, of the trees proposed for removal.
The submittal defers replacement to construction drawings and does not specify replacement species, sizes, locations, or in-lieu fees.
Oregon oak is a protected native tree under the ordinance. Oregon oak and valley oak are among the native oaks susceptible to the Mediterranean oak borer (Xyleborus monographus), an invasive ambrosia beetle that carries pathogenic fungi. The beetle is established in Sonoma, Napa, and Lake counties, where it has killed native oaks, and trees weakened by construction stress are more vulnerable to attack. Coast redwood is a large, long-lived species with shallow, wide-spreading roots that are sensitive to grade changes, soil compaction, and altered drainage, and it depends on consistent soil moisture.
ANSI A300-2023 Tree Care Standards and the ISA Best Management Practices: Managing Trees During Site Development and Construction, third edition, establish the accepted methods for tree protection zones, protective fencing, root pruning, mulching, and construction monitoring. A tree protection zone is generally set at or beyond the dripline and adjusted for species tolerance by the project arborist.
Conclusions
The submitted materials are adequate as a basic tree inventory, but they do not meet the tree protection plan
Urban Forestry Associates July 21, 2026
8100 Valentine Avenue Development Tree Review
requirements of Sebastopol Municipal Code 8.12.050. Before the City can condition this project effectively, and before I can complete a protection review, the applicant should prepare and submit a tree protection plan, including a plan sheet, prepared by the project arborist. I recommend that the City require the applicant to clarify or provide the following.
1. A tree protection plan sheet, drawn over the civil site plan, that shows in plan view each tree to be removed, each tree to be retained and protected, and the tree protection zone and fencing location for each retained tree. The plan sheet shall translate the report's numeric recommendation codes into plain protection notes a contractor can follow.
2. Field re-tagging of the inventoried trees, or another unambiguous method of identifying each numbered tree on the ground, because most tags were missing at the time of my inspection.
3. Correction of the species identification for Tree 52 from valley oak to Oregon oak, with a corresponding review of its retention, replacement, and pest-risk implications.
4. Application of the correct protected-tree threshold. The property is currently developed with a former church and is not an existing single-family or duplex residential property. Therefore, under Sebastopol Municipal Code 8.12.040, the protected-native-tree threshold is a 10-inch trunk diameter rather than 20 inches.
Applying the correct threshold adds Trees 12, 13, 14, 27, and 42 to the protected-tree count. Based on the dispositions presently shown on the tentative map, the site contains 23 protected native trees, of which 12 are proposed for retention and 11 are proposed for removal. The protected-tree schedule and required mitigation shall be recalculated accordingly.
5. Reconciliation of the tree inventory, numbering, and disposition schedules. The inventory report states that 46 trees were evaluated, but its inventory chart contains 47 entries, numbered 10 through 56. Tree 54 is identified as an off-site tree and is not included in the tentative map's on-site disposition lists. The inventory location plan also labels Tree 57, but no corresponding Tree 57 entry appears in the inventory chart. In addition, the inventory report states that there are 18 protected trees, while the tentative map identifies 19 and the written project description refers to 15 "heritage trees." The applicant shall provide one definitive schedule identifying the location, species, diameter, protection status, and proposed disposition of every numbered tree.
6. Tree protection zones and measures specified for each retained tree, including fencing distances, grading and trenching restrictions, mulch, and required arborist monitoring, consistent with ANSI A300-2023 Tree Care Standards and the ISA Best Management Practices: Managing Trees During Site Development and Construction, third edition. Protection notes shall use the words shall and must.
7. A replacement and mitigation plan under Sebastopol Municipal Code 8.12.060(E) that specifies replacement species, sizes, locations, and any in-lieu fees, rather than deferring these to construction drawings.
8. Inventory and protection of the neighboring trees whose driplines extend onto the site. Under Sebastopol Municipal Code 8.12.050, the tree protection plan must include trees on adjoining property whose dripline is within the development area, so these trees shall be added to the inventory. The plan shall require protective fencing and arborist oversight for any work within their root zones.
9. A construction-phase protection and monitoring program for the coast redwoods in the northeast corner, including Tree 32. The final landscape and irrigation plan shall maintain soil moisture within the redwood root zones and shall not introduce planting or irrigation that is incompatible with the retained trees.
For Tree 52, I recommend that it be reclassified as a removal, or that the site plan be modified to provide it a survivable growing space. The canopy is asymmetric and weighted over Building 22, and Oregon oak is susceptible to the Mediterranean oak borer, so the construction stress expected at this location makes long- term retention unlikely.
Urban Forestry Associates July 21, 2026
8100 Valentine Avenue Development Tree Review
Works Cited
Adobe Associates, Inc. 8100 Valentine Avenue Development: Vesting Tentative Map Package. July 2026.
City of Sebastopol. Sebastopol Municipal Code, Chapter 8.12, Tree Protection. Current through Ordinance No. 1164, passed March 3, 2026.
Fordyce, Lauren. "Mediterranean Oak Borer: Questions & Answers." Pests in the Urban Landscape, University of California Agriculture and Natural Resources, May 28, 2025.
Grupe Investment Company, Inc. Project Description: For-Sale Missing Middle Single-Family Home Development at Sebastopol, 8100 Valentine Avenue. December 18, 2025; updated May 21, 2026.
Matheny, Nelda, E. Thomas Smiley, Ryan Gilpin, and Richard Hauer. Best Management Practices: Managing Trees During Site Development and Construction. 3rd ed., International Society of Arboriculture, 2023.
Meserve, John C. Tree Inventory Report, 8100 Valentine Avenue, Sebastopol, California. Horticultural Associates, December 5, 2025.
Oregon Department of Forestry. Mediterranean Oak Borer. May 2026.
Tree Care Industry Association. ANSI A300-2023 Tree Care Standards. 2023.
University of California Statewide Integrated Pest Management Program. "Coast Redwood." UC IPM.
University of California Statewide Integrated Pest Management Program. "Protecting Trees During Construction." UC IPM.
Scope of Work and Limitations
Urban Forestry Associates has no personal or monetary interest in the outcome of this investigation. All observations regarding trees in this report were made by UFA, independently, based on our education and experience. This review was limited to a visual site inspection and evaluation of the submitted plans and tree- related materials. I did not perform a complete independent tree inventory, subsurface root investigation, or tree risk assessment. Internal and belowground conditions were not investigated, and these conclusions may require revision if the project plans or observed site conditions change.
Benjamin Anderson, Urban Forester
ISA Board Certified Master Arborist & TRAQ
RCA #686, WE #10160B
(415) 454-4212
2 (W-Trans
August 25, 2026
Mr. John Jay
City of Sebastopol
714 Johnson Street
Sebastopol, CA 95472
Focused Transportation Impact Study for 8100 Valentine Avenue Development
Dear Mr. Jay;
As requested, W-Trans has prepared a focused transportation impact study for the proposed residential development at 8100 Valentine Avenue in the City of Sebastopol. The purpose of this letter is to address the project's potential transportation effects related to trip generation levels, traffic safety, and adequacy of emergency access and onsite circulation.
Project Description
The project as proposed includes 20 Single-Family Detached (SFD) homes with 19 detached Accessory Dwelling Units (ADU). The site is currently occupied by a vacant church building that is no longer in operation. Vehicular access to the project site would be provided through a single driveway on Valentine Avenue, at the same location as the existing driveway to the church. The project also includes a 12-foot-wide emergency vehicle access (EVA) linking the end of its internal drive aisle to Valentine Avenue.
Trip Generation
The anticipated trip generation was estimated using standard rates published by the Institute of Transportation Engineers (ITE) in Trip Generation Manual, 12*h Edition. For the 20 SFD dwelling units, trip generation rates for Single Family Detached (SFD) Housing (LU #210) were used. For the 19 detached ADUs, trip generation was estimated with rates for a specialized land use commonly referred to as "patio homes." A patio home is a detached housing unit that is located on a small lot with little (or no) front or back yard, and is typically smaller than standard single- family homes, along with having lower average household sizes. Trip rates for patio homes are provided as a special subset of the Single Family Detached Housing land use. Based on the application of these rates, the proposed project would be expected to generate an average of 284 trips per day, including 19 a.m. peak hour trips and 28 trips during the p.m. peak hour. These results are summarized in Table 1.
Table 1 - Trip Generation Summary
Land Use Units Daily AM Peak Hour PM Peak Hour
Rate Trips Rate Trips In Out Rate Trips In Out
Primary Residences 20 du 9.09 182 0.70 14 4 10 0.93 19 12 7 SFD Housing
Accessory Units 19 du 5.35 102 0.26 5 1 4 0.47 9 6 3
SED-Patio Homes'
Total Trips 284 19 5 14 28 18 10
Note: du = dwelling unit; LU = ITE Land Use; 'Specialized land use described under Single-Family Detached Housing (LU #210) in ITE Trip Generation 12' Edition
490 Mendocino Avenue, Suite 201 Santa Rosa, CA 95401 707.542.9500 w-trans.com SANTA ROSA • OAKLAND
Mr. John Jay Page 2 August 25, 2026
Sight Distance
As proposed, the project site would be served by a single full-access driveway on Valentine Avenue. Sight distance at the proposed driveway was evaluated in accordance with the intersection sight distance criteria presented in the Caltrans Highway Design Manual (HDM). The HDM recommends corner sight distance for public street intersections based on the prevailing approach speed of through traffic.
Although the posted speed limit on Valentine Avenue is 25 mph, a field speed survey conducted along the project frontage found that the average operating speed of vehicles is approximately 30 mph. At the posted speed of 25 mph, the HDM recommends minimum corner sight distances of 275 feet for left-turn departures and 240 feet for right-turn departures. Based on the observed average operating speed of 30 mph, the recommended corner sight distances increase to 330 feet for left-turn departures and 290 feet for right-turn departures.
Valentine Avenue is generally level in the vicinity of the project site. To the east, the horizontal alignment of the roadway is straight with no obstruction to the line of sight. The intersection of Valentine Avenue and Pleasant Hill Avenue, located approximately 400 feet east of the proposed driveway, is clearly visible from the driveway departure point. To the west, a horizontal curve begins approximately 240 feet from the driveway. Because the curve deflects away from the driver's line of sight, visibility extends beyond the curve, providing approximately 500 feet of available sight distance.
Finding - Available sight distance from the proposed driveway measures approximately 400 feet to the east and 500 feet to the west. These distances exceed the minimum corner sight distance criteria for both left- and right- turn departures based on the observed average operating speed of 30 mph. Therefore, the proposed driveway provides adequate sight distance for ingress and egress.
Collisions
Collision records obtained from the California Highway Patrol's Statewide Integrated Traffic Records System (SWITRS) were reviewed to identify any collision patterns or trends that may indicate safety concerns associated with roadway geometry or traffic control along Valentine Avenue in the vicinity of the project site. The most recent SWITRS data available covers the five-year period from 2020 through 2024.
During the five-year study period (2020-2024), two reported collisions occurred on Valentine Avenue, with no collisions recorded at or in the immediate vicinity of the proposed project driveway. The collision nearest the project site occurred approximately 800 feet east of the site and involved a driver who unlawfully crossed into the opposing lane and struck a parked vehicle. The second collision occurred at the Valentine Avenue/Zimpher Drive intersection and involved an impaired driver colliding with a roadside fixed object.
Based on the reviewed collision records, both reported collisions were attributable to driver error rather than deficiencies in roadway geometry or traffic control. Accordingly, no identifiable traffic safety issues were found in the vicinity of the project site that would warrant roadway or traffic control improvements.
Warrants Evaluation
Left-Turn Lane Warrants
The need for a left-turn lane on Valentine Avenue for vehicles returning to the project site was evaluated based on criteria contained in the Intersection Channelization Design Guide, National Cooperative Highway Research Program (NCHRP) Report No. 279, Transportation Research Board, 1985, as well as an update of the methodology developed by the Washington State Department of Transportation and published in the Method for Prioritizing Intersection Improvements, January 1997. The NCHRP report references a methodology developed by M. D.
Mr. John Jay Page 3 August 25, 2026
Harmelink that includes equations that can be applied to expected or actual traffic volumes to determine the need for a left-turn pocket based on safety issues.
The p.m. peak hour was selected for the left-turn lane warrant analysis because the project trip generation estimates (Table 1) indicate that the project would generate more inbound vehicle trips during the p.m. peak hour than during the a.m. peak hour. The directional distribution of project inbound trips was based on the 2023 Sonoma County Travel Demand Model (SCTM), which indicates that westbound traffic on Valentine Avenue is approximately three times greater than eastbound traffic during the p.m. peak hour. Accordingly, it was assumed that 75 percent of project inbound trips would approach from the east and turn right into the project driveway, while the remaining 25 percent would approach from the west and turn left. Of the projected 18 inbound trips during the p.m. peak hour, approximately five eastbound vehicles on Valentine Avenue are expected to turn left into the project driveway, while the remaining 13 vehicles would turn right from westbound Valentine Avenue.
Using these assumptions, the left-turn lane warrant analysis indicates that a left-turn lane would be warranted only if opposing westbound through traffic on Valentine Avenue reached approximately 1,390 vehicles per hour and concurrent eastbound through traffic reached approximately 464 vehicles per hour. These volumes are equivalent to average traffic flow rates exceeding 20 westbound vehicles per minute and 8 eastbound vehicles per minute throughout the p.m. peak hour.
Traffic count data are not currently available for Valentine Avenue. However, field observations conducted during the speed survey recorded traffic flow rates of approximately three to four westbound vehicles per minute and one to two eastbound vehicles per minute during the p.m. peak hour, corresponding to approximately 210 westbound and 90 eastbound vehicles per hour. These observations are consistent with forecasts from the 2023 SCTM, which estimates 203 westbound vehicles and 72 eastbound vehicles on Valentine Avenue during the p.m. peak hour.
Both the field observations and the SCTM forecasts indicate that existing traffic volumes on Valentine Avenue are substantially below the volumes required to satisfy the left-turn lane warrant criteria. Therefore, the conditions necessary to warrant a left-turn lane at the proposed project driveway are not expected to occur.
Finding: A left-turn lane is not warranted on eastbound Valentine Avenue at the proposed project driveway.
Emergency Access
The proposed project includes a single, approximately 545-foot-long drive aisle that would serve all parking areas and day-to-day traffic generated at the site. The drive aisle would be 26 feet wide. The project also proposes an approximately 200-foot long, 12-foot-wide drivable landscaped surface that is intended to be available as a secondary emergency route connecting the terminus of the internal drive aisle to Valentine Avenue. The project description states that the homeowner's association will ensure that this route is maintained and remains clear of obstructions.
The 26-foot drive aisle width would accommodate emergency ingress and egress, with fire equipment able to navigate the drive aisle bend based on review of the fire truck maneuverability exhibit in the project's tentative map. Consistent with preliminary feedback provided by Gold Ridge Fire officials during their review of the site plan, curbs on both sides of the drive aisle and turnaround should be painted red in areas without designated parking.
The proposed drive aisle would be a dead-end roadway. While a secondary emergency access is proposed from the end of the drive aisle to Valentine Avenue, its 12-foot width would be inadequate to accommodate passage by fire trucks. Consistent with preliminary feedback provided by Gold Ridge Fire representatives, modification of the site plan to either extend the drive aisle back to Valentine Avenue as a loop or widen the emergency access to Mr. John Jay Page 4 August 25, 2026
at least 24 feet would be preferable to the current design. Any modifications would need to be confirmed as adequate and consistent with applicable fire codes by the Gold Ridge Fire Chief.
If creating a loop drive aisle or widening the emergency access are deemed infeasible, emergency responders will need to rely on the hammerhead type turnaround at the end of the internal driveway. Provision of a hammerhead is generally consistent with State Minimum Fire Safe Regulations (California Code of Regulations Title 14, Section §1273.05), though it is unclear whether the hammerhead design as proposed would be sufficiently sized for fire trucks to effectively turn around. During detailed reviews of the project, it is recommended that Gold Ridge Fire representatives confirm that the proposed hammerhead configuration would adequately accommodate turnaround maneuverability for the fire department's equipment.
While the proposed 12-foot-wide emergency road may accommodate passenger vehicle-sized emergency response vehicles, it would be inadequate for passage by fire trucks. Gold Ridge Fire officials should review the proposed configuration and provide more specific feedback on modifications that would be needed to commodate the department's emergency response vehicles and comply with applicable fire codes. If fir officials find a revised emergency access road configuration to be acceptable, it is recommended that removabl bollards or barriers be installed at each end of the emergency access to prevent non-emergency use of the road.
While the project description indicates that the roadway would be kept clear of all obstructions, it is also recommended that this requirement be reinforced through a condition of approval.
Importantly, fire officials retain ultimate authority regarding the adequacy of emergency access and compliance with all applicable local and State fire codes.
Finding - Modification of the site plan to either extend the drive aisle back to Valentine Avenue as a loop or widen the emergency access to at least 24 feet would be preferable to the current design.
Recommendation - Curbs on both sides of the drive aisle and turnaround in areas without designated parking should be painted red to ensure clear emergency access.
Recommendation - Gold Ridge Fire representatives should confirm that the proposed hammerhead configuration would adequately accommodate maneuverability for the fire department's equipment.
Recommendation - Removable bollards or barriers should be installed at each end of the emergency access, if allowed, to prevent non-emergency use of the road.
Recommendation - The City should consider adding a condition of approval requiring the emergency access road to remain clear of obstructions at all times.
Conclusions and Recommendations
• The project would be expected to generate an average of 284 trips per day, including 19 a.m. peak hour trips and 28 trips during the p.m. peak hour.
• Sight distances available at the proposed driveway departure point meet the recommendations for left- and right-turn maneuvers from the driveway.
• Based on collision records for the last five years, no identifiable traffic safety issues were found in the vicinity of the project site that would warrant roadway or traffic control improvements. • A left-turn lane is not warranted on Valentine Avenue into the project driveway.
Mr. John Jay Page 5 August 25, 2026
• Modification of the site plan to either éxtend the drive aisle back to Valentine Avenue as a loop or widen the emergency access to at least 24 feet would be preferable to the current design. • Curbs on both sides of the drive aisle and turnaround in areas without designated parking should be painted red to ensure clear emergency access.
• Gold Ridge Fire representatives should confirm that the proposed hammerhead configuration would adequately accommodate maneuverability for the fire department's equipment. • Removable bollards or barriers should be installed at each end of the emergency access, if allowed, to prevent non-emergency use of the road.
• The City should consider adding a condition of approval requiring the emergency access road to remain clear of obstructions at all times.
Thank you for giving W-Trans the opportunity to provide these services. Please call if you have any questions.
Sincerely,
Gaiiay Matter
Zachary Matley, AICP
Principal
ML/jzm/SEB920-6.L1
3 Ch. 16.40 Design and Improvement Standards | Sebastopol Municipal Code Page 1 of 4
16.40.040 Circulation.
A. The subdivision shall be consistent in concept, alignment and level of improvement with the Circulation Element of the General Plan, and any applicable specific plan, as well as any street connection policy. Where necessary to ensure traffic safety and ease of circulation, off- and on-site traffic control devices and improvements, such as signing, striping, signalization, traffic islands, channelization, access limits and provisions, turn lanes, etc., shall be required. On-site parking shall be required to meet zoning regulations.
B. Circulation design shall promote a grid street system, and curvilinear and cul-de-sac streets shall be generally discouraged.
Satisfactory access to the subdivision and to each lot shall be provided by public streets meeting all applicable standard specifications. Subdivisions with streets longer than 500 feet may be required to provide multiple access.
Access shall be deemed satisfactory only if it will allow reasonable ingress and egress for emergency vehicles.
Private streets shall not normally be permitted. However, in the event a public street is not necessary for future street connections, a private street may be permitted upon a finding by the City Council that a private street is justified because of the topography or other natural features of the land or because of limitations imposed by adjacent developed property. In such case the subdivider shall be required to provide a feasible method for maintenance of, and parking enforcement on, such private streets), which shall be subject to the approval of the City Engineer and City Attorney.
D. Street design shall take into consideration the use of provisions which discourage fast, through traffic on neighborhood connector and local streets; however, traffic measures which restrict traffic at the expense of the overall interconnectedness and coherence of the City should be avoided. Measures which should be considered include, but are not limited to, the following: appropriate street width; use of median islands; use of traffic circles, bulbouts and textured crosswalks at intersections; alleys.
E. All streets shall be designed and constructed to ensure the public health, safety and welfare, and to meet the relevant standards set forth in the City of Sebastopol Standard Details and Standard Specifications and Fire Department specifications. In addition:
1. Where a subdivision abuts upon an arterial or congestion management plan segment as identified in the transportation chapter of the General Plan, the City Engineer may require parallel service roads and may limit the right of access to the street or highways.
2. The frontage of each lot shall be improved to its ultimate geometric section to the centerline of the street, including street structure section, curbs, sidewalks, driveway approaches and transitions. Where necessary to provide adequate circulation and safety, two-way traffic flow shall be provided by sufficient pavement construction beyond the centerline of the street.
3. All streets shall, as far as practicable, be in alignment with existing and adjacent streets by continuation of centerlines, or by adjustment by curves, and shall be in general conformity with the plans made for the most advantageous development of the area in which the subdivision lies. Streets shall be required to The Sebastopol Municipal Code is current through Ordinance 1168, passed August 4, 2026. 4 Ch. 15.04 International Building Code | Sebastopol Municipal Code Page 1 of 16
15.04.120 California Fire Code.
Adoption of California Code of Regulations Title 24, Part 9: 2025 California Fire Code as published by the International Code Council, including Appendix Chapters 4, B, BB, C, CC, D, E, F, G, H, and O, with the following amendments:
Chapter 1, Administration.
California Fire Code Section 101.1 is amended to read as follows:
Section 101.1 Title Shall be revised to read: These regulations shall be known as the Fire Code of the City of Sebastopol, hereinafter referred to as "this code" California Fire Code Section 104.2.1 is amended to read as follows:
Section 104.2.1 Application for Permit Fees: All applications for a permit required by this Code shall be made to the Bureau of Fire Prevention in such form and detail, as it shall prescribe. Applications for permits shall be accompanied such plans as are required by the Bureau. The City Council may establish fees by resolution for permit applications.
California Fire Code Section 105.6 is amended to read as follows:
105.6 Required Operational permits. The fire code official is authorized to issue operational permits for operations set forth in Sections 105.6.1 through 105.6.50.
California Fire Code, Section 105.6.50 is added to read as follows:
105.6.50 Local permits. In addition to the permits required by section 105.6, the following permits shall be obtained from the Bureau of Fire Prevention prior to engaging in the following activities, operations, practices or functions:
1. Apartment, hotel, or motel. An operational permit is required to operate an apartment house, hotel or motel.
2. Care Facilities. An operational permit are required to operate a care facility as listed:
3. Day care with an occupant load greater than eight (8) persons.
The Sebastopol Municipal Code is current through Ordinance 1168, passed August 4, 2026. des / California / 2025 California Fire Code, Title 24, Part 9 with January 2026 Errata v ›PENDIX D FIRE APPARATUS ACCESS ROADS 5
A
SECTION D107-ONE- OR TWO-FAMILY RESIDENTIAL DEVELOPMENTS D107.1 One- or two-family dwelling residential developments.
Developments of one-or two-family dwellings where the number of dwelling units exceeds 30 shall be provided with two separate and approved fire apparatus access roads.
Exceptions:
1. Where there are more than 30 dwelling units accessed from a single public or private fire apparatus access road and all dwelling units are equipped throughout with an approved automatic sprinkler system in accordance with Section 903.3.1.1, 903.3.1.2 or 903.3.1.3, access from two directions shall not be required.
2. The number of dwelling units accessed from a single fire apparatus access road shall not be increased unless fire apparatus access roads will connect with future development, as determined by the fire code official.
D107.2 Remoteness.
Where two fire apparatus access roads are required, they shall be placed a distance apart equal to not less than one-half of the length of the maximum overall diagonal dimension of the property or area to be served, measured in a straight line between accesses.