Andrew Murray
City of Vallejo
September 24, 2025
Request for Concurrence in Writing
Caltrans is requesting City of Vallejo’s concurrence with Caltrans’ Section 4(f) de minimis determination for SME, as it pertains to land under the City’s jurisdiction. Signing this letter does not indicate agreement by the City of Vallejo for land use or limit the City’s rights under the Uniform Relocation Act that govern Right of Way activities.
This concurrence is necessary to proceed with the review and approval of the Project. If you require any additional information on this matter, please contact me directly by phone at (510) 496-9551 or via email at [email protected]. We appreciate your involvement and support on this project.
Sincerely,
Skylar Nguyen
Senior Environmental Scientist, SR 37 Corridor Projects Caltrans District 4
The signature below acknowledges that Caltrans has explained its Section 4(f) findings pertaining to the use of City of Vallejo’s land under temporary occupancy and the City’s concurrence with the de minimis determination. This signature would complete the Section 4(f) compliance process pursuant. This acknowledgement does not limit City of Vallejo’s rights during the PS&E phase concerning the right of way process for temporary construction access use at SME.
Andrew Murray
City Manager
City of Vallejo
“Improving lives and communities through transportation.”
Project Limits
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FIGURE 1
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Strip Marsh East Enhancement Project
Description
THIS VERSION CONTAINS UPDATES AND EDITS FROM THE STRIP MARSH EAST AUDUBON TEAM, 4/8/24
April 2025
Strip Marsh East Enhancement Project Description ii
Contents
Strip Marsh East Enhancement Project Description .....................................................1
1. Introduction ...........................................................................................................1
2. Location ................................................................................................................1
3. Site Background ....................................................................................................2
4. 1996 Caltrans Mitigation Project ..........................................................................3
5. Existing Conditions ...............................................................................................4
6. SME Enhancement Goals and Objectives ............................................................7
6.1. Goals .........................................................................................................8
6.2. Primary Objectives ....................................................................................8
6.3. Secondary Objectives ................................................................................8
7. Coordination .........................................................................................................8
8. SME Enhancement Activities Overview ..............................................................9
8.1. Proposed Project Elements Overview .....................................................10
8.2. Design Elements Update from April 2024 Preliminary Design Report and DSEIR ..................................................................................11
9. Design Elements .................................................................................................15
9.1. Element 1: Lower Berms Along Pond 1/1A Intake Channel ..................15
9.2. Element 2: Enlarge and Extend Intake Channel .....................................16
9.3. Element 3: Create Interior Channels and Mid-Marsh Benches ..............17
9.4. Element 4: Reverse Subsidence within the Site Interior .........................19
9.5. Element 5: Reverse Subsidence Adjacent to Intake Channel Berms ......................................................................................................21
10. Anticipated Ecological Outcomes .......................................................................21
11. Post Construction Monitoring and Adaptive Management ................................25
11.1. Monitoring to Meet Outcomes Assessment and Identify Potential Concerns .................................................................................................25
11.2. Site Adaptive Management Actions to Remedy Identified Outcomes Concerns ................................................................................27
12. SME Construction ...............................................................................................28
12.1. Construction Approach ...........................................................................28
12.2. Construction Schedule and Sequencing ..................................................31
12.3. Equipment Mobilization and Site Access ...............................................32
13. References ...........................................................................................................33
Strip Marsh East Enhancement Project Description iii
List of Figures
Figure 1. Strip Marsh East Location Map ....................................................................... 1 Figure 2. Perennial Emergent Marsh Loss at Strip Marsh East: 2001-2021 .................. 3 Figure 3. 1996 Caltrans Constructed Drainage Ditch Network ...................................... 3 Figure 4. Existing Topography – 2024 LiDAR DEM .................................................... 5 Figure 5. Bathymetry of Northern San Pablo Bay .......................................................... 5 Figure 6. Current (2023) Site Ecogeomorphic Units ...................................................... 7 Figure 7. SME Enhancement Elements Overall Layout ............................................... 13 Figure 8. West End Design Focus................................................................................. 13 Figure 9. Typical Section for Intake Channel Berms Modifications ............................ 16 Figure 10. Schematic of Central Channel Typical Cross Section ................................. 19 Figure 11. Subsidence Reversal .................................................................................... 21
List of Tables
Table 1. Design Elements Updates Rationales ............................................................. 11 Table 2. Design Elements: Quantities Summary .......................................................... 14 Table 3. Projected Probabilistic Low-End Habitat Changes with Enhancement of Strip Marsh East Interior Basin (Year 10) ............................................ 24 Table 4. Monitoring Metrics and Methods ................................................................... 26 Table 5. Proposed Monitoring Schedule ....................................................................... 27 Table 6. Potential Site Adaptive Management Actions ................................................ 27 Table 7. Preliminary Construction Equipment List ...................................................... 32
Strip Marsh East Enhancement Project Description iv
List of Abbreviated Terms
Caltrans California Department of Transportation
CDFW California Department of Fish and Wildlife
FIGR Federated Indians of Graton Rancheria
Pond 1/1A intake
channel
Leslie Salt constructed a bay water intake channel in 1953 through the marsh unit
HTL high-tide line
MHHW mean higher high water
MHW mean high water
MTC Metropolitan Transportation Commission
NAVD88 North American Vertical Datum of 1988
NMFS National Marine Fisheries Service
Refuge San Pablo Bay National Wildlife Refuge
RWQCB Regional Water Quality Control Board
SCE Sonoma Creek East unit of the Refuge
SCW Sonoma Creek West unit of the Refuge
SFEI San Francisco Estuary Institute
SME Strip Marsh East unit of the Refuge
SPMIIP Sears Point to Mare Island Improvement Project
SR State Route
U.S. EPA United States Environmental Protection Agency
USFWS U.S. Fish and Wildlife Service
Strip Marsh East Enhancement Project Description 1
Strip Marsh East Enhancement Project Description
Caltrans would enhance approximately 600 acres of degraded habitat to restore approximately 230 acres of former emergent salt marsh habitat, 50 acres of tidal channel habitat, and 320 acres of tidal flats from existing winter lagoons/summer barrens and convert about 11 acres of uplands to wetlands and waters. These enhancements would benefit protected species and resources at the Strip Marsh East (SME) unit of the U.S.
Fish and Wildlife Service (USFWS)-managed San Pablo Bay National Wildlife Refuge (Refuge). Land ownership is predominantly California State Lands Commission (long- term lease to USFWS), a small area along SR37 at the Pond 1/1A intake structure owned by the California Department of Fish and Wildlife (CDFW), and a small portion along SR 37 and Figueras Tract in the east owned by the USFWS.
1. Introduction
SME is included as a minimization measure to the overall Sears Point to Mare Island Improvement Project (SPMIIP) because it would create new habitat types critical to threatened and endangered species through actions to enhance marsh ecological conditions. Following environmental and public review, SME will be further refined with respect to design, schedule for implementation, and responsible parties. SME is not in the California Department of Transportation (Caltrans) right-of-way and will remain under the management and control of the Refuge and CDFW for the area at the Pond 1/1A intake structure. Construction of the SME enhancement may be carried out separately from construction of the highway elements to allow selection of appropriately qualified contractors for these two different efforts.
2. Location
The SME unit of the USFWS-managed Refuge is in Solano County. It lies between State Route (SR) 37 on the north, San Pablo Bay on the south, the Pond 1/1A Intake Channel and Sonoma Creek East (SCE) unit of the Refuge to the west, and Mare Island on the east. SME is about 3.5 miles east-to-west and 0.6 mile north-to-south. SME serves two major functions: habitat for a variety of marsh-dependent species and nature-based shoreline protection for SR 37. The Project’s study area includes SME and areas immediately adjacent to SME (Figure 1).
Figure 1. Strip Marsh East Location Map
Strip Marsh East Enhancement Project Description 2
3. Site Background
The Strip Marsh East tidal marsh built outwards atop bay mudflats through sedimentation during the twentieth century, with a majority of the marsh having formed since the 1940s and having reached most of its current extent by the 1980s. A series of subdued low marsh ridges, representing relict shoreline positions between flats colonized by marsh vegetation, was evident in the emerging Strip Marsh East during the mid-twentieth century. The outer bayfront marsh berm, formed by waves like a chenier ridge, naturally obstructed shore-normal (north-south) drainage of the prograded marsh. The resulting absence of internal tidal creeks, rills, and gullies, and the low-relief topographic rise of coarser mixed sediments at the shoreline, formed a large interior basin typical of chenier plain marshes worldwide. In 1953, Leslie Salt, a salt-producing company in the San Francisco Bay Area, constructed a bay water intake channel through the marsh unit (hereafter referred to as the Pond 1/1A channel). The channel was mechanically dredged, and material from the excavation was side-cast to create berms on the eastern and western sides of the channel. The resulting berms further obstructed drainage from SME to the west. Combined with drainage barriers formed by Mare Island to the east and the natural Bayshore ridge to the south, this led to seasonal flooding and water impoundment in the low-elevation internal basin.
As sea levels and climate extremes increased over the decades, the impoundment of rainwater, extreme spring tide flooding, and intermittent wave and storm overtopping of the bayfront berm increased. This increased inflow and lack of drainage increased the duration of marsh flooding through the spring and sometimes into early summer growing season. In the summer and fall after evaporation and infiltration dried the site, soils concentrated salts resulting in increased shallow soil salinity. Marsh vegetation drowning and dieback because of repeated and prolonged inundation and increasingly hypersaline soils began its severe trajectory in the 1990s, after the end of severe drought that exacerbated poor soil conditions. The loss of perennial emergent tidal marsh at over time SME and the expansion of this loss into SCE to the west is shown in Figure 2. These areas of emergent marsh loss currently alternate between winter-spring shallow lagoons, some of which support widgeon grass meadows, and summer-fall dry barrens (these areas are referred to hereout as “winter lagoons/summer barrens” and “interior basin”). The SME interior basin soils subsequently underwent erosion and oxidation down toward the Bay Mud substrates, which in turn increased the duration of submergence periods in wet years.
Strip Marsh East Enhancement Project Description 3
The bayfront marsh edge is experiencing shoreline retreat. The San Francisco Estuary Institute (SFEI) found shoreline accretion for the measured period of 1993 to 2010 switching to shoreline retreat for 2010 to 2018 (SFEI 2020).
Figure 2. Perennial Emergent Marsh Loss at Strip Marsh East: 2001-2021
4. 1996 Caltrans Mitigation Project
In 1996, as a mitigation action, Caltrans cut two small drainage ditch networks in the interior of SME in response to marsh drowning and dieback. Western and eastern ditch networks were created in the SME interior with the intent of improving drainage to the Pond 1/1A channel and San Pablo Bay. The western ditch network was constructed by expanding and extending (to approximately 10 feet wide by 5 feet deep) an existing drainage ditch that connected to the Pond 1/1A intake channel and by constructing nine lateral drainage channels (approximately 4 feet wide by 3 feet deep) extending south from this ditch into the interior basin. The eastern ditch network cut a new channel (approximately 7 feet wide by 4 feet deep) that meanders through the interior basin and connects to the bayfront mudflats at the eastern end of SME. Two small lateral ditch cuts (approximately 3 feet wide by 1.5 feet deep) were constructed off this eastern ditch.
Figure 3 shows the locations of this constructed drainage ditch network.
These ditches did improve drainage initially. However, all ditches soon filled with sediment and debris that accreted around them, restricting the lateral sheet flow from the flooded marsh. Accreted areas eventually established thick pickleweed vegetation that further restricted drainage. The interior marsh quickly returned to a cycle of prolonged flooding during the spring and, in some years, through summer growing season months.
This prolonged flooding and the resulting decrease in soil quality accelerated interior basin vegetation dieback.
Figure 3. 1996 Caltrans Constructed Drainage Ditch Network
Strip Marsh East Enhancement Project Description 4
5. Existing Conditions
Topography and Bathymetry. Site elevations vary by current conditions (Figure 4).
Remaining emergent marsh is found in the mid to upper intertidal range (5.5 to 6.5 feet NAVD88) and the winter lagoon/summer barrens are found below the emergent marsh down to the lowest site elevations of about 4.0 feet NAVD88. The perimeters of SME are above the elevation of local mean higher high water (MHHW) elevation. Along the bayfront edge, there is a high marsh berm, partially composed of dense wrack deposits and extending more than a foot above local MHHW in some locations. The berm on the eastern side of the Pond 1/1A intake channel has elevations of more than 11 feet NAVD88 at some locations. The berm on the western side of the intake channel is larger and reaches elevations of up to 14 feet NAVD88. The northern boundary of the site consists of SR 37 and the Figueras Tract levee; the eastern boundary consists of the Mare Island levee system, all of which create abrupt transitions to elevations above MHHW that are greater than 9 to 10 feet NAVD88. The only location around the site perimeter with intertidal elevations is the small gap in the Pond 1/1A intake channel east berm at the extreme northwestern corner of SME. Of the roughly 8.5‑mile SME perimeter, only about 15 feet (0.03 percent) occur below high tide.
The winter lagoon/summer flats in the marsh interior exhibit up to 1.0-1.5 feet of elevation variation. In addition, interior basin topography includes several isolated depressions that further exacerbate adverse hydrologic conditions.
The Pond 1/1A intake channel bottom depth varies from shallow subtidal to lower intertidal elevations (‑1 to +1 foot NAVD88) along its length. Generally, the channel becomes progressively deeper from the existing water control structure on the southern side of SR 37 south to where it enters the bay. A deep scour hole with elevations extending below ‑5 feet NAVD88 is present at the head of the channel, immediately below the Pond 1/1A intake structure. At the confluence with the bay, the channel forms a broad, shallow (approximately 0.5‑foot-deep) swale across the mudflat that dissipates as it crosses the mudflat. The distance that this swale persists across the mudflats is not known and may vary throughout the year based on the hydrologic management of Ponds 1/1A.
Northern San Pablo Bay is very shallow in the vicinity of the Project Area (Figure 5).
SME, like other fringing tidal marshes that occur along the northern bay shore, is bordered by broad intertidal mudflats that are up to 2,000 feet wide at SME. South of these intertidal mudflats, shallow subtidal bay bottom elevations gradually decrease toward the south to the San Pablo Bay Deepwater Shipping Channel. There are no continuous deepwater navigation channels in northern San Pablo Bay between the
Strip Marsh East Enhancement Project Description 5
Petaluma River to the west and the Napa River to the east. As a result, navigation in the vicinity of the Project Area is difficult and limited to higher tide stages that can accommodate shallow draft vessels for short high tide periods.
Figure 4. Existing Topography – 2024 LiDAR DEM
Figure 5. Bathymetry of Northern San Pablo Bay
Hydrology. There are three external drivers of the hydrologic regime at SME: tides, wind waves (both storm and summer winds), and rainfall. These drivers interact with SME topographic features though time. The interplay between these external drivers and site geomorphology dictates the inundation regime. Site inundation and desiccation cycles alongside salinity extremes are the primary controls of site ecology.
Winter rainfall and storm (wind) wave overwash are the primary water inputs to SME.
Early season rains first saturate site soils then subsequent storms generate ponding. The very poor drainage results in ponding lasting for one to three months following the end of the rainy season. How late ponding persists depends on the winter rainfall and when spring rains end.
The very small channel (a few feet wide and a few feet deep) at the northwest corner of the site at the northern end of the Pond 1/1A intake channel provides minimal tidal exchange to the site interior. Winter 2024 and early winter 2025 measurements found tidal variation within the interior of SME on the order of 0.1 feet or less. Periodic but generally not frequent wind-wave overtopping of the bayfront marsh edge during very high tides is the primary source of the limited bay waters that reach the site, with overtopping occurring mainly during winter storms that combine with extreme high tides.
Role of Offshore Bay Mudflats. The broad shallow Bay mudflats offshore of SME dampen wind waves and resuspend bay sediment which, along with floating debris, deposits along the bayfront marsh edge, incrementally raising this berm height and reducing future overtopping. Observed bay shoreline erosion in combination with projected sea level rise and higher intensity winter storms suggest this naturally formed berm may experience ongoing erosion and retreat into SME over time. Landward erosion of SME’s edge along San Pablo Bay has contributed to the gradual loss of this landscape feature. This long-term and large-scale change along the margins of San Pablo Bay may
Strip Marsh East Enhancement Project Description 6
continue to result in habitat loss, reduced topographic elevations in the marsh, reduced flood risk resiliency along SR 37, and other effects that could be further avoided or minimized by restoration of SME.
Sea-level rise is an external factor that affects the height of both high- and low-tide events, which in turn will continue to affect the frequency, depth, and duration of tidal flooding. At SME, sea-level rise will affect the cumulative time marshes are submerged at higher high tides, which can lead to gradual conversion from higher marsh to mid and lower marsh and, in decadal time scales, unvegetated mudflat. Deposition of sediments transported up the channel and over the bayfront berm can contribute to marsh accretion, though reductions in regional sediment supplies and sea level rise are expected to reduce available sediment. Thus, projecting sedimentation rates for SME has not been undertaken. These processes are outside the control of this Project and are considered in the design approach.
Habitats at Strip Marsh East. The Strip Marsh East landscape is composed of multiple, integrated “ecogeomorphic” units – conceptual divisions within the landscape where ecological and geomorphological processes interact to shape the environment (Figure 6). • Bay Edge Marsh Complex. The Bay Edge Marsh complex is composed of the landward-retreating, wave-built high salt marsh berm, bordering tidal marsh and San Pablo Bay tidal flats, separated by an active vertical wave-cut scarp (a steep bank or slope that separates two relatively flat areas with different elevations). • Outer Salt Marsh. The outer, bayward salt marsh terrace extends landward from the Bay Edge Marsh berm, ending where it intergrades with the winter lagoon/summer barrens. The outer salt marsh plain has a relatively consistent elevation and is almost entirely dominated by tall Pacific pickleweed (Salicornia pacifica). It is inundated by winter storms, winter wave overtopping, and borders interior seasonally ponded areas.
• Interior Winter Lagoon/Summer Barrens (“Interior Basin Flats”). During the winter and spring season, storm events and wave overtopping cause the interior basin flats of SME to become completely inundated with water. Meadows of widgeon grass (Ruppia maritima, a perennial, salt-tolerant aquatic herb) begin to regrow across portions of the interior basin. During summer months, the water has evaporated, leaving behind desiccated widgeon grass mats in many locations and hypersaline soils devoid of vegetation. Where widgeon grass does not establish, the interior basin flats are unvegetated substrate. The interior basin flats are barren of emergent wetland vegetation. The extent of widgeon grass across the interior basin flats varies within and between years. No data exists on its full extent and when it first appeared at SME.
Strip Marsh East Enhancement Project Description 7
The widgeon grass meadows intergrade with flooded pickleweed in a transition zone at the bayward edge of the interior basin flats (outer salt marsh). Widgeon grass meadows at SME are productive foraging habitat for dabbling and diving ducks, shorebirds, herons, and egrets. Widgeon grass is a Habitat of Concern as identified by the National Marine Fisheries (NMFS) Service under the Magnussen-Stevens Act. • Interior Salt Marsh. The only salt marsh vegetation remaining north of the interior basin is located along the highway embankment at the northwestern corner of SME, where some limited tidal connectivity to the ditch system remains. The narrow breach in the intake canal berm provides heavily muted tidal connection to a segment of a narrow (less than 3 feet of open water surface between its banks) and steep-sided ditch. Pickleweed in the vicinity of the tidally circulating ditch segment is thick and tall like the outer salt marsh. Pickleweed vigor and height diminishes rapidly with distance from the tidally circulating segment of the ditch. The lagoon is encroaching on this remnant salt marsh.
• Intake Channel and Fringing Marsh. The Pond 1/1A intake channel is approximately 15 to 20 feet wide along most of its length. Much of the original channel has infilled with parallel strips of pickleweed-dominated tidal salt marsh between the active channel and the adjacent intake channel berms. • Intake Channel Berms. These mostly upland berms support a weedy matrix of terrestrial vegetation, which includes coyote brush, upland mustards, poison hemlock, and fennel.
• Perimeter Ruderal/Uplands. Along the SME boundaries with SR 37 and the Mare Island levee system, the interior wetland and lagoon flats transition to adjacent levees and roadways. These upland areas around the perimeter are similar in vegetation composition to the intake channel berms and levee weedy flora in the vicinity.
Figure 6. Current (2023) Site Ecogeomorphic Units
6. SME Enhancement Goals and Objectives
SME enhancement goals describe the intended outcomes of proposed actions, and the objectives describe the measurable actions intended to minimize Project impacts on protected natural resources. It may not be possible to meet all the goals and objectives presented here, though the design aims to meet them all. Construction feasibility, environmental impacts, and costs are meaningful factors that may limit what can be achieved.
Strip Marsh East Enhancement Project Description 8
6.1. Goals
1. Provide for recovery and durability of habitat, habitat access, and ecological functions of SME perennial emergent marshlands for special-status fish, wildlife, and plants with potential to occur that use channelized emergent marsh.
2. Provide for durability of SME as natural flood attenuation and shoreline erosion protection for SR 37.
3. Beneficially reuse excavated sediment on site, to the greatest extent feasible.
4. Create new wetlands and waters connected to San Francisco Bay (this goal pertains to the broader SPMIIP).
5. Meet landowner and land manager requirements.
6.2. Primary Objectives
1. Convert extensive interior seasonal lagoon flats back to relatively continuous emergent salt marsh vegetation and habitat structure suitable for salt marsh harvest mouse and other marsh-dependent special-status fish and wildlife species, to the greatest extent feasible.
2. Increase elevations in the enhanced interior marsh over time through sedimentation and biomass accumulation, allowing marsh to keep pace with sea- level rise as much as possible; and support marsh vegetation, to the extent nature can provide.
3. Create high-water refuge habitat in the marsh interior for native small mammals, to increase resilience to extreme tides and storms associated with sea-level rise, if feasible.
4. Do not increase mosquito production in SME that would substantially increase treatment requirements at the Refuge.
5. Lower elevations of existing upland areas in SME to convert them to wetlands and waters, where appropriate and achievable (this objective pertains to the broader SPMIIP).
6.3. Secondary Objectives
1. Reduce or reverse rates of marsh erosion along the bayfront edge.
2. Create additional marsh channel habitat in the marsh interior to support primary management target fish and wildlife species in the Refuge, if feasible.
7. Coordination
Caltrans, Metropolitan Transportation Commission (MTC), and its county transportation partners coordinated and collaborated with state, federal, county, local, regulatory
Strip Marsh East Enhancement Project Description 9
partners and nonprofit organizations. Coordination among the Project Team and stakeholders has included the USFWS, Regional Water Quality Control Board (RWQCB), United States Army Corps of Engineers, United States Environmental Protection Agency (U.S. EPA), National Marine Fisheries Service (NMFS), San Francisco Bay Conservation and Development Commission (BCDC), CDFW, Federated Indians of Graton Rancheria (FIGR), the Yocha Dehe Wintun Nation, SFEI, Audubon Society, Napa-Sonoma Marsh Restoration Group, Baylands Group, SME landowners/ managers (USFWS, Refuge, and CDFW).
8. SME Enhancement Activities Overview
The Project would enhance drainage, establish regular tidal exchange, reverse subsidence, and create high water refugia and sea level rise accommodation space to improve ecological functions at SME. These ecological enhancements would be achieved through earth-moving activities in the SME interior, at the Pond 1/1A intake channel and adjacent berms, and a small amount in the SCE interior. The anticipated results would convert winter lagoons/summer barrens that replaced emergent tidal marsh since the late 1990s to a mosaic of estuarine habitats, including perennial emergent brackish and salt marsh, intertidal mudflats, tidal pans, tidal channels with vegetated banks, and high water refugia. Emergent vegetation anticipated within the tidally restored areas would be predominantly annual and perennial pickleweed (Salicornia bigelovii and Salicornia pacifica), Pacific cordgrass (Spartina foliosa), and alkali bulrush (Bolboschoenus maritimus). Higher elevation tidal marsh would be found on site margins and on marsh mounds intended to provide high tide refuge habitat and would include saltgrass (Distichlis spicata), frankenia (Frankenia salina), Jaumea (Jaumea carnosa), and marsh gumplant (Grindelia spp.). Adjacent to upland edges (such as along SR37), vegetation may consist of creeping wildrye (Leymus triticoides) and coyote bush (Baccharis pilularis) interspersed with non-native vegetation. This mosaic of vegetated tidal brackish to salt marsh habitats would support greater biodiversity when compared to the existing winter lagoon/widgeon grass mats and summer barren flats that dominate SME interior.
The proposed enhancement would support the threatened and endangered species that have historically occupied SME in greater densities than currently occur, would provide subtidal and intertidal channel and vegetated channel bank habitats not previously found at SME and that would support additional special status species, and it is expected to provide habitats that are persistent and resilient through all seasons, recognizing that over multidecadal time scales sea level rise will slowly shift these habitats to low marsh and mudflats.
Strip Marsh East Enhancement Project Description 10
8.1. Proposed Project Elements Overview
To achieve this ecosystem uplift, several construction activities would be included, which are summarized below with each described in the next section.
1. Lower berms along the Pond 1/1A intake channel. The berms on both sides of the intake channel would be lowered using land-based equipment. The east berm would be retained just above tide level initially to function as the containment berm for all the interior SME work and final lowering would occur following completion of interior work. Berms at the northern end within the CDFW property would be retained as upland refuge/sea level rise accommodation, and the remainder of the berms within the Refuge would be lowered mostly to high marsh refuge, with some areas retained as upland refuge/sea level rise accommodation and some converted to marsh swales (west berm) and the central channel (east berm).
2. Enlarge and extend the Pond 1/1A intake channel. Bay and marsh soils would be excavated from offshore mudflats, the intake channel, and tidal marsh alongside the intake channel to create a wider and deeper tidal connection between San Pablo Bay and SME. Excavation would take place with a combination of a suction dredge and/or barge-mounted excavator supported by land-based equipment along the intake channel berms.
3. Create interior channels and mid-marsh benches. Channels in the SME interior would be excavated using a suction dredge for the central channel and larger (northern) lateral channels and excavators for surface clearing and constructing smaller (southern) lateral channels. Containment berms to contain dredged sediment from the channel construction would be set back a short distance from the channels to create adjacent mid-marsh benches.
4. Reverse subsidence in site interior. Material generated in-situ from intake channel dredging, berm lowering and notching, and interior channel dredging and excavations would be placed into the SME interior to raise subsided lands. In-situ material sourced with land-based equipment would be directly sidecast or transported short distances and then spread across the SME interior with land- based equipment. In-situ material sourced with dredge equipment would be pumped from the excavation area via a pipe system and placed as a slurry in the SME interior. Low berms would be constructed along the central channel and large lateral channels to contain the dredge slurry.
5. Reverse subsidence adjacent to Pond 1/1A intake channel berms. A portion of the soils excavated from berm lowering would be utilized to reverse subsidence
Strip Marsh East Enhancement Project Description 11
within about 500 feet of each berm. These soils have been exposed to the air since intake channel construction in 1953 and thus have no sulfide toxicity or soil acidity concerns, allowing reuse to elevations above MHW. Subsidence reversal will utilize these soils to construct gentle gradient marsh slopes from the lowered berm elevations of 6.5 to 7.5 feet NAVD88 out to existing interior grades. West berm soils will be dispersed in a manner to direct drainage to three constructed marsh swales that would connect to the Pond 1/1A intake channel.
The following sections describe these design elements. Figure 7 illustrates the proposed design features for the entire SME enhancement project, and Figure 8 shows details for the west end design elements (intake channel dredging and berm lowering). Table 2 provides a summary of the impact footprints/quantities for the SME design elements.
8.2. Design Elements Update from April 2024 Preliminary Design Report and DSEIR
The April 2024 Preliminary Design Report (Audubon et al. 2024a) presented three design approaches for SME: minimal-intervention “sheet flow”, moderate intervention “channel- swale”, and maximum intervention “channel network”. The December 2024 DSEIR analyzed the impacts of the maximum intervention channel network approach to provide CEQA coverage for that or lesser-intervention proposed designs.
In the interim, numerous stakeholder engagement meetings took place, considerable new field data collection and technical analyses were carried out, a technical advisory committee was convened, and the fiscal outlook for implementation funding became more challenging. Table 1 lists the types of changes made to the SME design as a result and their specific rationale.
Table 1. Design Elements Updates Rationales
Design Change Rationale
Element 1: Intake Channel Berm
Lowering
• Original: lower most from uplands to
wetland
• Revised: retain as uplands northern
CDFW-owned lands and small
portion of Refuge-managed lands
• Difference: reduce upland-wetland
conversion acreage from about 17 ac
to 11 ac
4/1/25 meeting with Refuge and CDFW
land management staff illuminated that
CDFW wants its owned segments of the
berms and the Refuge wants some
sections of its managed berms retained as
uplands:
1) CDFW wants the protection the
upland berms offer to its Pond 1/1A
intake structure
2) CDFW and Refuge are not in
support of losing elevation in the
Strip Marsh East Enhancement Project Description 12
Design Change Rationale
face of sea level rise, noting that
these berms are a rare area for SLR
adaptation locally
3) CDFW and Refuge do not see full
berm lowering as a necessity to
remedy the SME drainage
impediments
Element 2: Enlarge and extend Pond
1/1A intake channel
• Original: enlarge fairly far north up
channel, two connections into SME
• Revised: enlarge minimum distance
up channel, one connection into SME
• Difference: reduced dredging and
removal of infill tidal marsh within
channel, keeps modifications further
from Pond 1/1A intake structure
1) Minimize impacts to existing
wetlands
2) Concern from CDFW that altering
hydrology at Pond 1/1A intake
structure could alter ecological
functions of Pond 1/1A
3) Reduce construction costs
Element 3: Create interior channel and
mid-marsh benches
• Original: Channel network largest
intervention of three design
approaches, channel centered in
deepest subsided depressions,
subsidence reversal on both sides of
channel and swale
• Revised: Hybrid between channel-
swale and channel network designs,
smaller channel, channel moved to
edge of deepest depression,
subsidence reversal on north side
only, swale (bench) north side of
central channel and both sides of
lateral channels
• Difference: Excavation volume
closer to channel-swale design,
greater certainty of tidal exchange
deeper into SME, simpler
construction
1) Stakeholder input that lessening
intervention while meeting goals and
objectives preferred
2) Lessen construction impacts and
simplify construction approach
3) TAC input and technical
considerations informed comparative
outcomes and risk considerations
4) Reduce construction costs
Strip Marsh East Enhancement Project Description 13
Design Change Rationale
Element 4: Subsidence reversal interior
basin
• Original: Extent across most of site
interior
• Revised: Reduced extent to north of
central channel and far eastern basin
• Difference: maximum extent of
1,270 acres reduced to 800 acres
1) Accommodate reduced dredge
volume while maximizing and
focusing subsidence reversal
2) Lessen construction impacts and
simplify construction approach
3) Reduce construction costs
Element 5: Subsidence reversal
adjacent to intake channel berms
• Original: details not specified
beyond marsh mounds and marsh thin
lifts, limits extent to ~500-ft from
berms for construction feasibility
• Revised: details now specified,
mainly thin lifts
• Difference: N/A
1) Aligns with excavation volumes
based on CDFW and Refuge input
on berm lowering approach
2) Thin lifts provide greater sea level
rise resiliency
3) Refuge specifically interested in thin
lift placement southeast of intake
channel-central channel confluence
Figure 7. SME Enhancement Elements Overall Layout
Figure 8. West End Design Focus
Strip Marsh East Enhancement Project Description 14
Table 2. Design Elements: Quantities Summary
Design Element Area (ac) Length (ft)
Excavation
Volume
(CY)
Fill
Volume
(CY)
EXCAVATION
1. Lower artificial berms
along Pond 1/1A
intake channel1
a. Excavate west berm to
create wetlands
9.73 2,200 25,000 0
b. Excavate east berm to
create wetlands
2,100 20,000 0
c. Excavate west berm to
create swales
0.79 300 10,000 0
d. Excavate east berm to
create central channel
0.62 200 2,000 0
SUBTOTAL, BERM SOILS CUT 11.14 4,800 57,000 0
2. Enlarge Pond 1/1A
intake channel and
extend across mudflat
Enlarge/extend existing
intake channel
8 3,000 65,000 0
3. Create interior
channels and mid-
marsh benches
a. Excavate Marsh Central
Channel
35 17,000 450,000 0
b. Excavate Marsh Lateral
Channels, north
11 15,000 70,000 0
c. Excavate Marsh Lateral
Channels, south
3 5,000 25,000 0
d. Establish mid-marsh
benches
40 N/A 0 0
SUBTOTAL, MARSH SOILS CUT 97 40,000 610,000 0
SOILS REUSE FOR SUBSIDENCE REVERSAL
4. Within the site interior
using marsh soils
Create Marsh Lifts/ Mounds
– SME
8002 N/A 0 610,000
5. Adjacent to intake
channel berms using
berm soils, to create
high marsh and high
tide refuge within
~500 feet of berms
a. West side reuse 19 N/A 0 57,000
b. East side reuse south
of central channel
4.5 N/A 0
c. East side reuse north of
central channel
6.6 N/A 0
1 5.97 ac of the berms will be retained as uplands, including all of the CDFW-owned berms and four segments along the Refuge-managed berms.
2 Total area available for subsidence reversal within SME. Actual area of fill may be reduced pending final design. A vast majority of subsidence reversal will be thin marsh lifts. Marsh mounds will be created from the dragged placement containment berms by cutting numerous notches in them.
3 Total area available for subsidence reversal in SCE within 500’ of western berm. Actual area of fill may be reduced pending final design.
AC = acres
CY = cubic yards
Ft = feet
N/A = not applicable
SCE = Sonoma Creek East
SME = Strip Marsh East
Strip Marsh East Enhancement Project Description 15
9. Design Elements
9.1. Element 1: Lower Berms Along Pond 1/1A Intake Channel The SME enhancement would involve excavating material from the berms on either side of the Pond 1/1A intake channel to eliminate the artificial barrier to tidal exchange within both the SME and Sonoma Creek East units and convert artificial uplands to wetland and water habitat. These berms are approximately 3,000 feet in length, the western berm slightly longer than the eastern berm. Lowering the eastern berm improves connectivity with the interior of SME, while lowering the western berm improves connectivity within the eastern extent of Sonoma Creek East, where emergent perennial marsh vegetation loss has been expanding in recent years. The Refuge requested in a letter dated March 25, 2024, that the western berm be lowered as part of this Project to improve tidal exchange in this management unit.
The approach to berm lowering has been further refined from that presented in Audubon et al. (2024a), which was not specific as to the details of berm modifications beyond those needed for site hydrology improvements. In a meeting on April 1, 2025, CDFW and Refuge staff indicated their desire to retain a portion of the berms as upland refugia for marsh wildlife, given that such habitat is extremely limited in SME and SCE. CDFW required that the berms on their property be left at upland elevations, while the Refuge requested that a portion of the berms on their property be left at upland elevations to provide islands of upland refugia within the matrix of restored tidal marsh.
Taking Refuge and CDFW input into account, the intake channel berms would be modified into four habitat types (Figure 8):
1) Upland refuge and long-term sea level rise accommodation – elevations will range from 7.5 feet NAVD88 up to elevations roughly between 10-14 feet NAVD88. These areas will include the CDFW-owned berm sections closest to SR37 (roughly 750 feet in length), which will be minimally graded for construction access and staging, and two sections of the southern Refuge reaches of each berm.
2) High marsh refuge – elevations will range from 6.5 to 7.5 feet NAVD88 (MHHW to +1 MHHW). These areas will be on the southern Refuge reaches of each berm.
3) Mid-marsh drainage swales (west berm only) – swale invert elevations will be about 5.0 feet NAVD88 and swales will extend across the infill tidal marsh within the intake channel to allow unimpeded drainage from the SCE interior.
Strip Marsh East Enhancement Project Description 16
4) Central channel (east berm only) – channel invert elevation will match the -4 feet NAVD88 of the central channel with SME interior and the enlarged intake channel.
Excavated berm soils have been aerated since 1953 and thus are well suited to construct high marsh above MHW and marsh mounds above MHHW without concern of accumulated sulfides or soil acidity impairing vegetation establishment. Localized reuse of excavated soils for subsidence reversal is described in Element 5, below.
Figure 9. Typical Section for Intake Channel Berms Modifications
9.2. Element 2: Enlarge and Extend Intake Channel
The Pond 1/1A intake channel will be the tidal connection to the interior of SME and aid in draining the east end of SCE. San Pablo Bay waters must cross shallow intertidal mudflats to reach this channel. Since its original creation in 1953, the intake channel has largely infilled with pickleweed-dominated salt marsh over decades. Based on historic aerial photograph interpretation, the channel was approximately 120 feet wide when it was constructed in the early 1950s. Natural infill has narrowed the channel to 15 to 20 feet wide along most of its length. The current intake channel and shallow offshore mudflats are too constrained to accommodate the additional tidal prism (volume of water flowing between high and low tide) that the proposed channels and marsh plain within a reconnected SME interior would require to support enhancement goals.
The proposed SME enhancement would involve dredging the Pond 1/1A intake channel and portions of the adjacent mudflats in San Pablo Bay to the target design geometry (Figure 8). In the offshore section of this channel, it would be dredged to a bottom width of 120 feet with 1:1 side slopes. The channel will have an invert elevation of -4 ft NAVD88 extending from the mouth of the intake channel approximately 750 ft south (to the 1.5 ft NAVD88 contour line). The invert will then rise to -2 ft NAVD88 and taper over approximately 1,100 ft to daylight at the 0.5 ft NAVD88 (MLLW) contour line.
Within the Pond 1/1A intake channel, it would be dredged to a bottom width of 120 feet with 1:1 side slopes and invert elevation of -4 ft NAVD88 for 600 feet until it turns into the SME interior.
Strip Marsh East Enhancement Project Description 17
9.3. Element 3: Create Interior Channels and Mid-Marsh Benches The SME enhancement is intended to improve internal site hydrology by cutting channels into the SME interior to increase flows into and drainage from the site interior and connecting these channels to the enlarged Pond 1/1A intake channel to the open bay. To develop the interior channel design presented here, the design team first developed three preliminary design options (“sheet flow,” “channel-swale,” and “channel network”; Audubon et al. 2024a) and assessed their relative efficacy in addressing the excess inundation problem through hydrodynamic modeling (Moffatt & Nichol 2025). The design team also collected “lessons learned” data (geomorphology, hydrology, and vegetation) from the nearby Sonoma Creek West restoration project that utilized a very similar design approach, and collected new data at SME (avian use, topography and bathymetry, surface water levels and salinity, surface and subsurface geotechnical soils properties, and subsurface sediment quality). Parallel to these technical efforts, the design team worked with AECOM, MTC, and Caltrans to engage numerous entities for their input – landowners, land managers, tribes, regulatory and resource agencies, and conservation and research organizations. The design team also established a small Technical Advisory Committee (TAC) to obtain review and input and explored technical considerations raised by the TAC. Caltrans presented the three enhancement design scenarios to the USFWS Refuge managers in a preliminary design report and discussed them in a meeting on March 6, 2024. The Refuge provided comments and support for the implementation of the channel network scenario as their preference in a letter dated March 25, 2024, with requests for additional coordination and clarification on the design as it proceeds.
Figure 7 presents the proposed interior channel network design. This enhancement design reflects a hybrid approach that blends elements of the “channel-swale” and “channel network” design options in Audubon et al. (2024a). It makes six specific revisions to the original channel network concept presented in the 2024 design:
1. The channel geometries are reduced from the original 2024 design across much of the network.
2. The central channel is moved from its original location in the center of the deepest subsided areas, with subsidence reversal on both sides of the channel, to the southern side of the interior basin, with subsidence reversal on the north side of the channel only (see subsidence reversal in Section 9.4 below and Figure 10).
Strip Marsh East Enhancement Project Description 18
3. The network has one vs. two connections to the Pond 1/1A intake channel and the single connection is moved further south toward the bay.
4. A modest-width (varying 25-50 feet) mid-marsh channel bench (inset swale) is included on the north side of the central channel and on both sides of northern lateral channels.
5. The intersection of the interior channel with the Pond 1/1A intake channel is now a gradual curve rather than a perpendicular intersection.
6. The separate stand-alone channel between the far eastern depressional basin direct to the bay has been eliminated.
The proposed channel geometries are based to date on a combination of three primary factors: (1) marsh tidal prism considering subsidence reversal, (2) preliminary hydrodynamic modeling results showing high ebb velocities that may induce scour, and (3) subsurface geotechnical data supporting likelihood of natural scour to enlarge channels where necessary. For final design, the channel network will be subject to additional hydrodynamic modeling to determine whether further geometry adjustments are needed.
The channel network will consist of a large central channel running east to west, with uniform width/depth tapering down from the Pond 1/1A intake channel at the west end toward the far eastern end of the site (Figure 7). At the west end, the channel will have a bottom width of 120 ft and invert elevation of -4 ft NAVD88 and it will taper uniformly to the east end which will have a bottom width of 20 ft and invert elevation of -2’ NAVD88. Side slopes will be 1:1, the channel will cover 35 acres over its 17,000 feet of length, and approximately 450,000 cubic yards of sediment will be excavated.
Several secondary lateral channels radiate off the central channel. The exact number and location will be adjusted during final design, with the total length and volume remaining close to that presented in Table 2. On the north side, eight lateral channels will be excavated with bottom widths of 20 feet, invert elevations of -2 feet NAVD88, and side slopes of 1:1. On the south side, five channels will be excavated to reach depressional areas within the extant emergent marsh with 10 feet bottom width, invert elevations of -2 feet NAVD88, and side slopes of 1:1. Excavated soils will be used to create marsh mounds at elevations no higher than 1 foot above MHHW and marsh lifts up to MHHW.
The proposed interior channel network is expected to provide semidiurnal tidal hydrology (experiencing two complete tidal cycles in one day) throughout much of the site interior,
Strip Marsh East Enhancement Project Description 19
with tidal range (the difference in height between high tide and low tide), and flows (horizontal movement at flood and ebb currents) diminishing somewhat eastward, away from the tidal source. The eastern end of the Project site would experience some degree of tidal damping due to the extreme distance from the tidal source.
Figure 10. Schematic of Central Channel Typical Cross Section
9.4. Element 4: Reverse Subsidence within the Site Interior Construction of the various elements described in the preceding sections would generate approximately 670,00 cubic yards of excavated soils in total (Table 2). Of this amount, about 60,000 cubic yards comes from the two intake channel berms and will be reused adjacent to those berms (see Element 5 below). The remaining approximately 610,000 cubic yards would be used for subsidence reversal within the subsided interior basin of SME. Of this 610,000 cubic yards, most is generated via dredging the central and lateral channels and intake channel, while a smaller amount is generated from scraping surficial soils in the channel footprints with land-based equipment. The approaches for reusing these different types of soil are described below.
A key constraint to soil reuse at SME is the fact that estuarine marsh soils (particularly soils from marshes with limited tidal exchange) are high in iron sulfides and when exposed to air oxidize to sulfuric acid. Promoting vegetation colonization requires the avoidance of acid sulfate soils, sulfide soil phytotoxicity, and hypersalinity in shallow soils. Though quantitative data on soil sulfides at SME have yet to be collected, it is assumed that sulfide toxicity and soil acidification are risks that must be managed. These concerns can be minimized through avoiding long wetting and drying cycles, promoting high frequency tidal exchange, keeping reused marsh soils naturally high in sulfides sufficiently wet by placing them at or below MHW, and utilizing previously aerated marsh soils for higher marsh features. Where shallow marsh soils are placed at elevations above MHW modest amounts of oxidation and soil acidification can be mitigated by natural flushing due to winter rains and inundation during higher tides (VanZomeren et al. 2020). All of these strategies are built into the SME design. Design guidance and risk assessment on these considerations is found in VanZomeren et al. (2020), NRCS (2023), and other technical publications.
Marsh Mounds (High Marsh and High Tide Refuge) from Temporary Containment Berms. To construct containment cells for dredge placement, surficial soils within
Strip Marsh East Enhancement Project Description 20
channel footprints would be scraped with land-based equipment to form low berms about 1 foot above MHHW. Following completion of dredge placement, land-based equipment would return to these berms, cut numerous gaps in them to provide effective tidal exchange, and place the soils adjacent to the remaining berm sections. The “islands” between the gaps then become curvilinear “marsh mounds” up to 25 feet wide with lengths varying between roughly 250-1,500 feet and crest elevations up to 7.5 feet NAVD88 (after allowing for compaction and consolidation). These mounds will be distributed throughout the SME interior basin alongside all the constructed channels (see Figure 7). A total length of roughly 45,000 linear feet of containment berms will be constructed and thus a subset of this total length, after excavating numerous gaps, will become the curvilinear interior marsh mounds. As containment berms, these soils will have been exposed to air for at least one full season to oxidize soil sulfides which then are expected to be flushed out with rainfall and high tide events. Any impairments to vegetation colonization due to soil acidification are anticipated to be short in duration.
Dredge Slurry Thin Layer Placement (Thin Marsh Lifts). Slurried dredged sediments from constructing the central channel and northern laterals and enlarging/extending the Pond 1/1A intake channel would be used to create thin marsh lifts within the SME interior ranging from 0.25 to 1.5 ft in depth and not exceeding the elevation of MHW (5.8 ft NAVD88). Figure 11 shows the maximum extent and depths of thin layer placement across the site. As described above, containment berms would be constructed from locally excavated surface soils to form cells for containing the dredge slurry, which would be breached prior to opening the SME site to the tides (see Construction Methods below and conversion of these berms to marsh mounds above). Most of the placement areas will be within the winter lagoons/summer barrens (650 acres of the maximum 800 acres of reuse placement). These areas would be colonized by emergent marsh vegetation through natural colonization and spread from adjacent intact tidal marsh. Thin layer placement within existing emergent marsh would extend across approximately 140 acres with an average thicknesses of 0.3 (±0.3) feet. Existing emergent vegetation in these areas is expected to continue to grow following thin layer placement, as observed at other marsh restoration sites in the SF estuary.
All reuse is predicated on soil quality meeting screening criteria. If testing determines that the soils at SME exceed established contaminant levels for use on site, options would be considered for reuse of the soils in upland areas not associated with SME, removal of the soils to a suitable landfill, or leaving the soils on site (not excavated).
Strip Marsh East Enhancement Project Description 21
Figure 11. Subsidence Reversal
9.5. Element 5: Reverse Subsidence Adjacent to Intake Channel Berms
Soils excavated from berm lowering will be utilized to reverse subsidence within about 500 feet of each berm (Figure 8). This earthwork would be conducted with land-based equipment. These soils have been exposed to the air since intake channel construction in 1953 and thus have no sulfide toxicity or soil acidity concerns, allowing reuse at elevations above MHW. Subsidence reversal will utilize these soils to construct three distinct features:
1) Gentle-gradient marsh slopes. The elevation of these slopes would extend from the lowered berm elevations of 6.5 to 7.5 feet NAVD88 down to match interior grades. On the SME side, the lower elevation would be where it meets the thin- layer dredge placement of 5.75 feet NAVD88. On the SCE side, the lower elevation would be where the soils meet existing elevations, with unfilled areas retained to allow drainage to the three constructed marsh swales graded to drain to the Pond 1/1A intake channel.
2) Marsh mounds. Mound elevations would be 1 foot above MHHW (7.5 feet NAVD88) after settling and compaction. These mounds would be relatively small (in the range of 25’ by 100’) with roughly 5:1 side slopes. Mounds may be distributed within or adjacent to the gentle-gradient marsh slopes. 3) Thin lift placement. Berm soils would be placed on what would become the south side of the central channel just east of its confluence with the enlarged Pond 1/1A intake channel. This area encompasses approximately 4.5 acres and would have soils placed up to 6.5 feet NAVD88 (roughly MHHW). The purpose of soils placement here is to build up subsided marsh elevations interior of the bayfront marsh and berm so as to promote resiliency where the tides enter SME. This location was identified at the request of the USFWS Refuge.
10. Anticipated Ecological Outcomes
In the near-term (5 to 10 years post-construction), the project would permanently convert the winter lagoon/summer barrens area to a mosaic of perennial tidal salt and brackish emergent marsh, tidal channels, vegetated channel banks, tidal mudflats, ponds and pans, and high tide refugia. This mosaic of tidal wetland habitats would enhance and increase
Strip Marsh East Enhancement Project Description 22
(in area and diversity) habitat elements that are vital to focal threatened and endangered species in the Project area.
Following construction, three broad processes are anticipated to take place with their rates driven by natural processes: establishment of emergent marsh vegetation through natural colonization, adjustment of the channel network through scour and deposition, and marsh plain accretion through deposition of suspended sediments. These processes alone and in combination will drive the ecological progression within the interior basin at SME. In parallel, ongoing erosion of the bayfront edge and accumulation of storm debris along the bayfront berm is anticipated to continue. The anticipated developmental trajectory of the major habitat types created by the project are summarized below.
The tidal channels are designed with deep intertidal to subtidal bottom elevations and are anticipated to remain open water habitat, though the terminal ends of the channels may silt in and become colonized by vegetation. The tidal channel banks and adjacent mid- marsh benches would establish vegetation cover through natural recruitment by California cordgrass and alkali bulrush (depending on winter-spring ambient salinity conditions). They would be expected to establish continuous low cordgrass marsh emerging near the MHW elevation starting at the tidal source. The eastward extent of cordgrass marsh is uncertain; it would depend on the final design dimensions of the new channel network and the duration of marsh hypersalinity events during summer neap tides (the seasonal period of moderate tides) . Marsh mounds along the edges of the mid marsh benches (constructed from former containment berms) would be colonized by high marsh vegetation including pickleweed, saltmarsh gumplant, fleshy jaumea, frankenia and saltgrass.
The winter lagoon/summer barrens within the site interior, which would be raised mostly to MHW elevations through subsidence reversal, would evolve into a matrix of vegetated emergent marsh interspersed with unvegetated intertidal mudflats, ponds, and pans. After initial tidal reintroduction, the site will be primarily intertidal mudflat before vegetation colonization takes off. Marsh areas likely will be colonized initially by annual pickleweed which is often replaced within a few years by perennial Pacific pickleweed as the dominant vegetation. At these and slightly lower elevations, colonization by alkali bulrush and Pacific cordgrass may take place, with species dominance depending on inundation regime and salinity. The higher marsh areas within the interior would see colonization by pickleweed initially and over time by other common higher marsh species, including marsh gumplant, fleshy jaumea, frankenia, and salt grass. These patterns of colonization are likely to begin earlier in the western reaches of SME closest to the tidal source and progress east over time as sediment accretion takes place. Patterns
Strip Marsh East Enhancement Project Description 23
and specific species of colonization will depend on wet/drought conditions and associated salinity variability, erosion and accretion, and localized inundation conditions.
Where persistent adverse substrate and groundwater conditions (e.g., hypersalinity, sulfide accumulation, and acid sulfate soils) occur in areas that still experience limited tidal exchange (primarily concentrated at the far eastern end of SME), pioneer plant colonization could be inhibited after tidal restoration, and may require years of tidal flushing or sediment burial to become receptive to plant colonization (Audubon et al. 2024a). Differential salt marsh accretion rates near the head of tide may re-isolate some areas as pans and ponds —but smaller in extent than existing conditions, and subject to tidal flooding on spring tide series. New ponds would likely be always submerged and receive consistent tidal exchange twice daily; they are expected to be more ecologically productive than the existing summer-desiccated lagoon beds. The submerged tidal pans and ponds are expected to support fish and invertebrate populations that are not supported under existing conditions.
Along the lowered/regraded intake channel berms, a mosaic of high marsh, transitional, and upland habitat will develop. High marsh areas up to the HTL will be colonized by habitat similar to the marsh mounds, transitioning to upland vegetation, including creeping wildrye, coyotebrush, and common non-native upland vegetation (mustard, fennel, poison hemlock) above this elevation.
The projected area of SME habitat change by type for the proposed tidal channel network design was estimated at the initial completion of enhancement construction and at 5 and 10 years after construction, based on an analysis of habitat evolution at three nearby restoration projects: Sonoma Baylands, Sonoma Creek West, and Lower Tubbs Island (Audubon et al. 2024b). By analyzing aerial images of the three nearby restoration projects, the establishment of new emergent marsh vegetation over time was plotted to develop a probability distribution of potential low and high estimates for perennial emergent marsh restoration at SME. At all three nearby restoration sites, the marsh elevations and channels were newly constructed/established, producing a major shift in hydraulic regime and emergent marsh habitat that resulted from progressive vegetation colonization of unvegetated mudflats, ponds, or pans. This analysis indicates that within 5 years, emergent marsh vegetation may be established across 15% (low end) to 80% (high end) of the existing interior seasonal lagoon area. At the 10-year point, between 45% (low end) and 85% (high end) of the existing seasonal lagoon may be converted to emergent marsh. Table 3 summarizes the estimated lower-end restoration outcome at SME by year 10 for the proposed project design, based on the low-end projections for emergent marsh establishment. It is also important to note that the processes that will
Strip Marsh East Enhancement Project Description 24
drive future marsh change at SME may differ from those at the other sites examined to develop this estimate.
Table 3. Projected Probabilistic Low-End Habitat Changes with Enhancement of Strip Marsh East Interior Basin (Year 10) Scenario
Channels
(acres)
Interior Basin
Unvegetated Flats
(acres)
Emergent
Marsh
(acres)
Tidal Flats
(acres)
Total
(acres)
Existing Conditions 0 600 0 0 600
Year 0 50 0 0 550 600
Year 5 50 0 80 470 600
Year 10 50 0 230 320 600
The anticipated long-term trajectory after project implementation would be dependent on sea level rise changes, site response to external environmental factors, and sediment accretion. A brief professional judgement opinion on the potential long-term succession over time is presented here. Reestablishment of perennial emergent marsh (with subsidence reversal to gain immediate elevation capital) will maximize the resilience of the SME interior to drowning and mudflat conversion with sea level rise. However, the long term stability of the site in the face of predicted rates of long-term (end of century) sea level rise is uncertain. The large constructed tidal channel may erode and widen due to tidal prism increases driven by seal-level rise, and converting areas where cordgrass establishes after enhancement to open waters over time. The interior marsh accretion rates would not be likely to keep pace with sea- level rise after mid-century, especially towards the HTL at the eastern end, which will be an estuary-wide challenge. As sea levels increase as anticipated, pickleweed marsh would slowly convert to cordgrass and bulrush marsh. The outer pickleweed marsh would narrow to a barrier island marsh surrounded by open water (San Pablo Bay) on the southern side and cordgrass marsh and channel on the northern side (partially drowned SME).
The retreating bay edge consists of marsh scarps and micro-embayments cutting into the outer marsh platform. These micro-embayments can focus wind waves resulting in surge channels that preferentially cut deeper into the outer marsh. If these surge channels reach the interior unvegetated basin prior to emergent marsh re-establishing, head-cutting could accelerate, further destabilizing SME. Were these surge channels to reach the constructed central channel, two schools of thought describe possible outcomes. One school suggests these surge channels could then “jump” the central channel and proceed further north toward SR37. The other school of thought suggests wind-wave energy would be absorbed by the constructed central channel, diffusing the northward energy. Neither paths have
Strip Marsh East Enhancement Project Description 25
been explored further to date. Efforts to assess bayfront erosion in more detail and to assess the need for and range of potential interventions and respective efficacy will commence during permitting and final design, with outcomes driving possible adaptive management actions.
11. Post Construction Monitoring and Adaptive Management After completion of construction activities, Caltrans will implement a 10-year monitoring and adaptive management plan. Monitoring would assess post restoration conditions at SME and adaptive management measures would be implemented as needed to correct any adverse conditions (if any) that warrant remedy. A monitoring and adaptive management plan will be developed in coordination with USFWS Refuge managers and environmental regulatory agencies with jurisdiction during the Project’s final design and permitting stage.
11.1. Monitoring to Meet Outcomes Assessment and Identify Potential Concerns
The monitoring program will be designed to assess attainment of the SME project goals and objectives and identify potential adverse outcomes that may need to be remedied.
Table 4 provides a summary of project goals and objectives, performance metrics for assessing attainment/non-attainment, and associated monitoring approaches. Strip Marsh East has unique physical access challenges that impose limits on feasible field-based monitoring strategies. We have applied this feasibility lens in developing the proposed monitoring approaches. The monitoring program will rely heavily on remote sensing (fixed-wing airborne multi-spectral aerial photography and LiDAR) to document site- wide geomorphic and habitat (vegetation) conditions. Remote sensing would be supplemented with focused field-based surveys for ground-truthing and verification.
Other monitoring elements require focused field surveys (wildlife biology, jurisdictional habitat mapping, channel bathymetry) or deployment of instruments for continuous monitoring at specific locations (hydrology and water quality). Repeat fixed-position photography at representative locations (i.e., photo points) will document qualitative changes in physical and biological site characteristics over time, supplementing the quantitative monitoring elements. The full range of proposed monitoring elements (data collection activities), as summarized in Table 4, are listed below. The proposed schedule for these monitoring elements is provided in Table 5:
1. Repeat, fixed-position ground photography (photo points)
2. Site-wide fixed-wing airborne multi-spectral aerial photography and LiDAR, with focused vegetation and topographic surveys for ground truthing
Strip Marsh East Enhancement Project Description 26
o
3. Bathymetric channel surveys
4. Water level and water quality monitoring by continuously deployed instruments
5. Shorebird/waterbird surveys
6. Salt marsh harvest mouse surveys
7. Focused jurisdictional habitat mapping (lowered berm areas)
8. Mosquito monitoring (performed by Solano County MAD) Table 4. Monitoring Metrics and Methods
a Vegetation cover Multi-spectral aerial imagery, LiDAR b Vegetation communities Multi-spectral aerial imagery, LiDAR c Elevations LiDAR, bathymetric channel surveys
d Channel evolution Multi-spectral aerial imagery, LiDAR, bathymetric channel surveys
e Inundation regime Continuous water level monitoring
f Water quality Continuous water quality monitoring
g Shoreline change Multi-spectral aerial imagery, LiDAR h SMHM density SMHM surveys
i Avian use Shorebird/waterbird surveys
a Emergent marsh extent Multi-spectral aerial imagery, LiDAR b Elevation change over time LiDAR
c Shoreline edge retreat Multi-spectral aerial imagery, LiDAR a Volume placed Contractor volume tracking
b Placed elevation and extent Multi-spectral aeial imagery, LiDAR G-4 Convert uplands to wetlands Acres wetlands created Focused wetland delineation Multi-spectral aerial imagery
O-1 Convert interior basin to emergent
wetlands, ≥230 ac by Yr 10 Acres of new emergent marsh Same as G-1a,b,e O-2 Increase interior basin elevations over
time similar to rates of sea level rise Elevation change over time LiDAR a Target elevations and extent built LiDAR
b Vegetation communities Multi-spectral aerial imagery
O-4 Do not increase mosquito production Treatment effort applied Mosquito monitoring (Solano County MAD) a Target elevations and extent built LiDAR
b Vegetation communities Jurisdictional mapping of lowered berm, LiDAR, multi-spectral aerial imagery
O-6 Reduce or reverse bayfront edge
erosion Shoreline change Same as G-1g
a Extent of channels Same as G-1d
b Vegetation along channel banks Same as G-1a,b
Primary Objectives
G-3 Beneficially reuse site soils
# Goal/Objective Performance Metric Monitoring Methods
O-7 Create marsh channel and bank
habitats
Goals
G-1
Restore and enhance marsh habitats
for plants, fish and wildlife that are
durable to medium term sea level rise
Secondary Objectives
G-2
Preserve and enhance shoreline
erosion protection for SR37 durable to
medium term sea level rise
O-5 Lower berms to convert uplands to
wetlands
O-3 Create high-water refuge habitat
Strip Marsh East Enhancement Project Description 27
Table 5. Proposed Monitoring Schedule
11.2. Site Adaptive Management Actions to Remedy Identified Outcomes Concerns
For this project, the approach to adaptive management will involve analyzing monitoring data relative to the project performance standards that will be developed during permitting, determining which standards are in danger of not being met, identifying unintended adverse outcomes (if any), and implementing corrective actions to set the project back on course. The final adaptive management plan will include a list of potential management actions that could be implemented if an associated “trigger” (qualitative or quantitative threshold condition) related to a specific performance standard is met. A preliminary list of potential adaptive management actions and associated qualitative triggers are provided in Table 6. The decision on whether to implement adaptive management measures, and the particular details of those measures, will be made in consultation with the land managing entities (CDFW and USFWS).
Table 6. Potential Site Adaptive Management Actions
Trigger Potential Action Purpose
Isolated areas develop on the
marsh plain with restricted
drainage and persistent
inundation
Construct small lateral
channels into isolated
impoundments
Introduce tidal exchange/
drainage to isolated areas
Invasive plants of ecological
concern establish and expand in
high marsh/ transitional areas
Implement invasive plant
control measures and
additional native vegetation
planting
Minimize or eliminate
invasive plants and
promote establishment/
0 1 2 3 4 5 6 7 8 9 10
Repeat Fixed-Position Ground Photgraphy (photo
points) Summer X X X X X X X X X X X
Multi-Spectral Aerial Imagery, LiDAR Summer/Fall X X X X X X Field verification - topo surveys Summer/Fall X X X X X Field verification - vegetation surveys Summer/Fall X X X X X Bathymetric Channel Surveys Summer/Fall X X X X X X
Continuous Water Level Monitoring November - July X X X X X Continuous Water Quality Monitoring Winter, Summer X X X X X Shorebird/Waterbird Surveys August - May X X X X
Salt Marsh Harvest Mouse Surveys Timing flexible X X X X Jurisdictional Mapping of Lowered Berm Timing flexible X X1 X1 X1 Mosquito Monitoring (by Solano County MAD) Ongoing X X X X X X X X X X X 1 Only performed if the targeted acreage of wetlands did not establish by the prior monitoring event Monitoring Year
Monitoring Element Timing
Strip Marsh East Enhancement Project Description 28
Trigger Potential Action Purpose
expansion of native
plants
Vegetation is slow to develop in
areas far from tidal and
vegetative propagule sources
Implement targeted
revegetation efforts (seeding,
planting, etc.)
Improve and accelerate
native vegetation
establishment
Accelerated and problematic
erosion of the bayfront edge
threatens to breach into the site
interior
Implement targeted or
comprehensive shoreline
treatments to prevent/slow
bayfront erosion and retreat
Halt or slow shoreline
erosion
12. SME Construction
The methods and equipment described herein represent what would likely be the most feasible and cost-effective approach to completing the work, however, the selected contractor may propose alternative construction approaches to accomplishing the work, based on equipment availability and preferences.
12.1. Construction Approach
Enlarge Intake Channel and Extend Across Mudflat. This design element involves widening and deepening the existing Pond 1/1A intake channel to provide the main tidal exchange point for the SME project. This element would involve construction within two different physical settings: (1) the offshore San Pablo Bay mudflats and (2) the existing intake channel and adjacent wetland/upland areas.
Dredge Channel Across the Mudflat. The Bay-side extent of the channel would likely be constructed first, as its construction would provide deep-water access for the marsh- side work. The channel would be dredged by a barge-mounted excavator/clam-shell dredge or a suction dredge working toward the site. The spoils generated from this dredging operation have one of two potential reuse approaches, depending on offshore sediment suitability for local subsidence reversal.
1. SME Subsidence Reversal (preferred approach): If a suction dredge is utilized, the materials would be pumped into the SME interior and thinly deposited for subsidence reversal. Rudimentary containment berms would be constructed to contain and evenly distribute the slurried sediment across targeted areas of the site interior (see discussion of approach below for interior channel construction). A Low Ground Pressure (LGP)/amphibious excavator would be required to move
Strip Marsh East Enhancement Project Description 29
the discharge pipe to different locations to ensure even distribution of the dredge spoils.
2. Off Site Disposal: Only if yet-to-be-conducted sediment quality testing determines these sediments are not suitable for wetland reuse, the dredge spoils could be excavated by clamshell dredge and loaded into a series of barges for transport to an in-bay disposal location. Given the shallow working conditions, small shallow-draft “hopper” barges (~200 CY capacity) would be required for transportation of dredged material. If sediment quality concerns exist, then larger project redesign may be needed.
Widen and Deepen Intake Channel. The marsh-side component of the channel construction would involve a combination of land and water-based equipment.
LGP/amphibious excavators would be used to excavate all surface wetland and upland (berm) soils to a minimum depth of ~2 ft below existing grade (BGS) to remove surface vegetation and rooted subsurface soils. This soil would be sidecast along the marsh interior side of the intake channel berms (on both the SME and SCE sides) or loaded into LGP/tracked dump trucks and relocated short distances along the berms to the reuse location where it would be spread across the marsh interior for subsidence reversal by bulldozer or amphibious excavator. Soil excavated from the intake channel tidal marsh and upland berm areas would be preferentially used to create marsh mounds, due to it having a low likelihood of acid sulfate production. The mounds or adjacent unvegetated barrens would be topped with the pickleweed material scraped from the tidal marsh areas to jump-start vegetation colonization. Reuse of this soil would be limited to areas within ~500 ft of the excavation location to minimize transport distances and disturbance to marsh habitats.
Below this surface excavation area (>2 ft BGS), the channel would be constructed in the same manner as the bay-side extent described above.
Lower Berms Along Intake Channel. Breaching and lowering the berms adjacent to the Pond 1/1A intake channel would be accomplished using excavators and bulldozers working from the berms and adjacent marsh areas. The soil removed from the berms would be spread in thin lifts extending out across the adjacent interior marsh basins and graded to drain toward the site interior. The maximum soil spreading distance from the berms would be < 500 ft though it may be possible to extend farther if upland berm soils are used to make thin lifts that can support more equipment tracking. Some of the soil may be loaded into LGP/tracked dump trucks and relocated short distances into the site interior where it would be used to create marsh mounds in specific locations.
Strip Marsh East Enhancement Project Description 30
Create Interior Channels. Increasing flows into and drainage from the interior of SME involves constructing a network of channels into the site interior. The internal channels would connect to the enlarged intake channel at the western end of the site. The breach through the eastern intake channel berm would be constructed by land-based LGP or amphibious excavators. Material excavated from the berm breaches would be sidecast and spread towards the site interior in thin lifts or used to create marsh mounds, as described above.
The channels would be constructed using a combination of land-based LGP/amphibious excavators and a water-based suction dredge (similar to the approach utilized for the intake channel dredging) or an excavator-mixed slurry and high solids pump system (excavator/pump system)1. LGP/amphibious excavators would be used to excavate all surface soils within the channel footprint to a depth of ~2 ft BGS to remove any surface vegetation and rooted subsurface soils. This surface soil would be used to construct low (~1-3 ft high) earthen containment berms on the north side of the central channel (and both sides of the norther laterals) to prevent dredge slurry from flowing back into the channel after it is discharged. Any excess surface material not used to create containment berms would be used to create marsh mounds on the south side of the central channel alignment. Below this surface excavation area (>2 ft BGS), the channels would be constructed by the suction dredge or excavator/pump system. The slurry would be pumped via a pipe or flexible discharge hose over the constructed containment berms to create thin marsh lifts across the site interior. An LGP/amphibious excavator would move the discharge hose along with the dredge to ensure even distribution of the dredge material. If necessary, lateral berms would be constructed from locally scraped surface material to segment the site into a series of containment “cells”. The small, short lateral channels to the south of the main channel alignment (into existing sparse pickleweed marsh areas) would be constructed using only the amphibious excavator, with the excavated material being sidecast to create marsh mounds along the channel alignments.
An alternative or supplemental approach to constructing lateral channels north of the central channel would be to excavate them following thin lift dredge material placement.
In this approach, placement cells would be drained to the ground surface and the excavator would then excavate channels within and below the placed sediment.
Excavated soils would be sidecast to make marsh mounds periodically along the path of constructed channels.
1 This system consists of an excavator cutting the channel and mixing the material into a slurry within the channel, which is then pumped out of the channel by a high-solids pump.
Strip Marsh East Enhancement Project Description 31
To keep the interior work area isolated from the tides during construction, a temporary earthen berm (crest elevation > +2 ft MHHW [8.5 ft NAVD88]), or temporary sheetpile cofferdam would be installed across the width of the channel where it passes through the intake channel berm at the western end of the site. The berm or cofferdam would include a flap gate or combination gate to allow tidewater into the interior channels, and contain the water as needed to provide makeup water for hydraulic dredging, while preventing the escape of high-turbidity water from the work area. This temporary barrier would be removed at the end of construction to introduce the tides to the site.
Water levels for dredging makeup water would be maintained within the interior through the inlet at the west end of the project as well as decant water flowing back into the channel from the slurry discharge areas. Since the system will be a ‘closed loop’ (isolated from San Pablo Bay), the decant water may be released back into the interior channels as makeup water without meeting turbidity thresholds, other than ensuring that the majority of the sediment has precipitated onto the thin lift area. This process may require multiple passes along the channel alignment with the dredge equipment as cells reach capacity, to allow time for decanting.
Any final distribution or shaping of the deposited thin marsh lifts would be done with LGP/amphibious equipment after decanting, when the material is decanted enough to be workable. Marsh runnels (narrow, shallow swales radiating off the main channels) would be constructed through the marsh lifts to ensure adequate drainage and exchange within the rehabilitated marsh interior. The temporary containment berms would be lowered to a mix of high marsh and marsh mounds using the same equipment.
12.2. Construction Schedule and Sequencing
Interior grading construction work would take place when SME is dry, generally June to November or December and dependent on specific climate conditions during the actual year of construction.
This timing also overlaps with appropriate dredge work windows for sensitive aquatic species that could potentially occur in the project vicinity. The schedule assumes there are no Ridgway’s or Black Rails within 750’ of the construction area. Under a situation in which interior channel construction occurs over two years, the site would be managed as a muted tidal system during the wet season between construction years by leaving the water control structure open (or partially removing the sheet pile wall).
The general sequencing of the construction activities would occur as follows. This sequencing may change based on the final project design.
Strip Marsh East Enhancement Project Description 32
1. Construct all or a portion of the interior containment berms along the proposed channel alignments (at least enough to contain intake channel dredging sediments).
2. Dredge the intake channel and offshore approach to the minimum geometry necessary to allow water access from San Pablo Bay and provide adequate channel depth for interior site water management.
3. Lower/breach the western intake channel berm and install a temporary cofferdam with a tide gate sized and at the elevation needed to ensure adequate makeup water for dredging.
4. Construct the interior channel network.
5. Concurrently, lower and breach the western intake channel berm.
6. Lower/breach temporary berms established for containment cells and perform final reworking of thin marsh lift material. This may include additional smaller lateral channel and runnel excavation.
7. Remove the temporary cofferdam to restore tides to the site interior.
8. Perform finish dredging of the intake channel and offshore approach to final design specifications.
12.3. Equipment Mobilization and Site Access
A preliminary list of the equipment required to perform the various construction activities described above is listed in Table 7.
Table 7. Preliminary Construction Equipment List
Design Element Equipment
Enlarge intake channel
and extend across
mudflat
• Barge-mounted excavator/clamshell or suction dredge
(x1)
• Barges – clamshell/excavator approach (x3)
• LGP/amphibious excavator – suction dredge approach
(x1)
• Bulldozer with swamp tracks – suction dredge
approach (x1)
Lower berms along intake
channel
• Conventional or LGP excavator (x1)
• Bulldozer (x2)
• LGP dump truck (x2)
Create interior channels • LGP/amphibious excavator (x2) • Bulldozer with swamp tracks (x2)
Strip Marsh East Enhancement Project Description 33
Design Element Equipment
• Barge-mounted suction dredge (x1) OR land-based
high-solids pump (x2)
SME is very difficult to access. Via land, there are two very small pullouts along SR 37 within the project extent, and perhaps access can be negotiated from Mare Island. For water access, the intertidal mudflats offshore greatly limit timing for access and the size of boats and barges that could access the marsh edge.
A temporary staging area will need to be constructed using the northern sections of the existing intake channel berms. Construction equipment would be delivered, offloaded, and staged at this location. Construction worker parking would be limited to this area as well, or workers would park elsewhere (e.g., Refuge Headquarters) and carpool to and from the staging area. Equipment mobilization from San Pablo Bay would have to take place during high tide due to the shallow depths along the bayfront edge and will need to dredge its own access to the site along the intake channel alignment. The very high tides during the late spring/early summer mobilization time period occur generally at night, requiring minimum lighting for safe navigation and operations during these times.
Temporary staging areas may be established within unvegetated areas of the interior basin, away from tidal channels and other areas of standing water.
Movement of land-based equipment within the interior basin and fringing tidal wetlands will require special considerations for the soft and semi-saturated soils. Low ground pressure (LGP) or amphibious equipment will be a necessity and work from construction mats may be required in some instances but should not be assumed due to the distances required to reach work areas. In addition, equipment fueling accommodations, such as fueling from barges or LGP tracked equipment will be required to reach the marine based equipment.
13. References
Audubon California, Siegel Environmental, Gillenwater Consulting, Restoration Design Group, and Peter Baye. 2024a. Preliminary Design Alternatives Memorandum.
Strip Marsh East Unit Restoration and Enhancement. Prepared for AECOM, Inc., Metropolitan Transportation Commission, and California Department of Transportation District 4. April.
_____. 2024b. Preliminary Habitat Outcomes Projections from Reference Sites, Strip Marsh East. Prepared for AECOM, Inc., Metropolitan Transportation Commission, and California Department of Transportation District 4. October.
Strip Marsh East Enhancement Project Description 34
Natural Resource Conservation Service (NRCS). 2023. Soil Survey Technical Note 430- SS-11, Acid Sulfate Soils in the Coastal and Subaqueous Environment. July.
San Francisco Estuary Institute (SFEI). 2020. New Life for Eroding Shorelines: Beach and Marsh Edge Change in the San Francisco Estuary. SFEI Publication #984.
Richmond, CA.
Toms, C., P. Baye, S. Siegel, D. Gillenwater, J. Lowe. 2022. SR 37 Strip Marsh East Near-Term Enhancement Actions Primer.
VanZomeren, C.M., J.F. Berkowitz, C.D. Piercy, and J.F.King. 2020. Acid Sulfate Soils in Coastal Environments – a Review of Basic Concepts and Implications for Restoration. U.S. Army Corps of Engineers, Engineer Research and Development Center. ERDC/ELSR-20-4.
--- Primary Ditch - 1996 Project
Lateral Ditch - 1996 Project
-- Other Ditches
Sources: Basemap (ESRI, 2023); D�ches (GillenH2O, 2023) �
Audubon cAL1FoRN1A
FIGURE 3
1996 Caltrans Constructed Drainage Ditch Network
Strip Marsh East Restoration Project
Solano Count , California
9§!!�
Gillenwater
Peter Baye, PhD GillenH20
Consulting
FIGURE 5
·;;: w
-� ic
0 8 w
�
"'
Existing Ecogeomorphic Units
- Bay Edge Marsh Complex
Intake Channel and Marsh
- Outer Salt Marsh
- Interior Salt Marsh
Interior Lagoon Flats
- Intake Channel Berms
- Perimeter Ruderal/Uplands
Reference Features
- Intake Channel Footprint
Interior SME Dtich Network
Note: Mapped distribution of marsh habitats
in site interior may not reflect current conditions
based on observed rates of marsh loss
1 :24,000 (1" = 2,000')
0 1,000 2,000
:::��;:::::::
0 300 600
Sources: Basemap (ESRI, 2024); Ecogeomorphic units (GillenH2O, 2024)' •derived from vegetation mapping data (AECOM, 2023)
� Audubon cAL1FoRN1A
FIGURE 6
Current (2023) Site Ecogeomorphic Units
Strip Marsh East Restoration Project
Solano Count California
Gillenwater
Peter Baye, PhD GillenH20
Consulting
Pon�i1/1A
Intake ,ructure
1 :24,000 (1" = 2,000')
--=:::::i ___
Primary Project Design Elements
- Retained Intake Channel Berms*
Q Graded/Lowered Intake Channel Berms*
- Enlarged/Extended Pond 1/1A Intake Channel*
Q Central Channel
- Lateral Channels (Representative)
Q Mid-Marsh Channel Bench
D Subsidence Reversal Area Boundary
0 0 1,000 2,000
--===---ft
� '------------------------------- 0=----------=3--=-c00'----------'6'-=-00=-------------------------- Sources: Basemap (ESRI, 2025); Design Elements (RDG, 2025) k ·Audubon cAL1FoRN1A
FIGURE 7
SME Enhancement Elements - Overall Layout
Strip Marsh East Restoration Project
Solano County, California
Gillenwater
GillenH20
Consulting
tJ CDFW Property Boundary
-- Bathymetry Contours (ft NAVD88)
Primary Project Design Elements
- Enlarged/Extended Intake Channel: bottom dredged to -4' NAVD88 Q Extended Intake Channel: bottom dredged from -2' to 0.5' NAVD88 Q Retained Upland Berm: Upland Refuge/SLR Accommodation Space (> 7 .5' NAVD88) Q Lowered Upland Berm: High Marsh Refuge (6.5' to 7 .5' NAVD88) - Lowered Upland Berm: Mid Marsh Drainage Swale (~5' NAVD88) Q Interior Channels w/Mid Marsh Bench
Subsidence Reversal Area Boundary
1:12,200 (1" =
0 500
--===---m
Pond 1/1A
Intake Structure
� L-------------------�0� __ 1�s�o _ __!3�00� _____ ......;:,, ____ _._;....:;.......::.�- Sources: Air Photos (ESRI, 2023);
Design elements (RDG, 2025);
Bathymetry (AECOM, 2017)
k ·:Audubon cAL1FoRN1A
FIGURE 8
West End Enhancement Design Focus
Strip Marsh East Restoration Project
Solano Count , California
Gillenwater
GillenH20
Consulting
Berm Modifications
C:=) Retained Upland Berm: Upland Refuge/SLR Accommodation Space C:=) Lowered Upland Berm: High Marsh Refuge
� Lowered Upland Berm: Mid Marsh Drainage Swale
12.0 11.0
10.0 I
9.0 8.0
7.0 z
,s 6.0
C
0 5.0
-� 4.0
3.0 2.0
1.0 0.0
8:>uth
,,.,,..._ ,,,..--.. ,> �,,---1 ��...,-.,, .. ��"'"""'"""-" / ., ,
(',.
.. ,,.,# �
__ ( __________________ High M3rsh R=fuge
''--1----------- --r---------
•J
0 12.0
11.0 10.0
I
9.0 8.0
7.0 ,s 6.0
C
0 5.0
·1 4.0
[D
3.0 2.0
1.0 0.0
500
8:>uth
0 ' ' ' -�---------------' -�----------------' '
,,_,,
500
1000
Central
Olannel
Section A:. W:!st Benn Profile
t
Md M3rsh SNale
1500 2000
Stationing (ft)
Section B: East Benn Profile
1000
Upland
Refuge
1500
Stationing (ft)
Other Design Elements
� Enlarged/Extended Intake Channel
C:=) Interior Channels w/ Mid Marsh Bench
2500
2000
North
-----· Existing Grade
-- Proposed Grade
3000
North
Minor grading for
construction acces&'stagng
(not shown)
-----· Existing Gade
-- Proposed Gade
2500 3000
::;; ...... ____________________________________________________ ...... Sources: Air Photos (ESRI, 2024); Topo (C&P, 2024); Design data (RDG/GillenH2O, 2025)
k ·:Audubon cAL1FoRN1A
FIGURE 9
Intake Channel Berm Modifications
Typical Sections
Strip Marsh East Restoration Project
Solano County, California
Gillenwater
GillenH20
Consulting
FIGURE 10
Schematic of Central Channel Typical Cross Section
Strip Marsh East Restoration Project
Solano County, California
Figure File: Fig-8_Typical XS Primary Channel Scematic_2025-0406sws 25-50’ setback
bench at EG
Bottom width varies 20-120’
Thin layer
placement
Central
channel
North South
Existing Grade
Proposed Grade Not to scale
• Placement thickness varies up to 1.5’
• Width of placement varies up to ±2,000’
Containment berms
converted to curvilinear
marsh mounds (not shown)
Depth varies to
-2’ to -4’ NAVD88
CONSENT CALENDAR 8.H.
DATE: November 4, 2025
TO: Mayor and Members of the City Council
FROM: Kristin Pollot, AICP, Planning and Development Services Director Bill Collins, Chief Building Official
SUBJECT: INTRODUCTION OF AN ORDINANCE ADOPTING BY REFERENCE, PURSUANT TO GOVERNMENT CODE SECTION 50022.2 AND CALIFORNIA CODE OF REGULATIONS TITLE 24, THE 2025 CALIFORNIA BUILDING STANDARDS CODE, PARTS 1 THROUGH 12, AND THE 2024 INTERNATIONAL PROPERTY MAINTENANCE CODE, AND
ADOPTING LOCAL AMENDMENTS THERETO IN ACCORDANCE WITH CALIFORNIA HEALTH AND SAFETY CODE SECTIONS 17922, 17958, 17958.5, 17958.7, AND 18941.5,
AND FINDING THE ADOPTION OF SUCH CODES AND AMENDMENTS EXEMPT FROM
THE CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA) PURSUANT TO CEQA GUIDELINES SECTION 15061(b)(3)
RECOMMENDATION
Introduction of an ordinance adopting by reference, pursuant to Government Code section 50022.2 and California Code of Regulations Title 24, the 2025 Building Standards Code Parts 1 through 12, and the 2024 International Property Maintenance Code, and adopting local amendments thereto in accordance with California Health and Safety Code Sections 17922, 17958, 17958.5, 17958.7, and 18941.5, and finding the adoption of such codes and amendments exempt from the California Environmental Quality Act (CEQA) pursuant to CEQA Guidelines section 15061(b)(3).
REASONS FOR RECOMMENDATION
The State Legislature requires local governments to adopt the most recent editions of the model codes related to building standards, rules and regulations, along with any local amendments as reasonably necessary in accordance with state law. On January 1, 2026, the 2025 California Building Standards Code, also known as the California Code of Regulations (CCR) Title 24, will go into effect. These regulations are applicable to all structures in all cities and counties in California. In addition, adoption of the International Property and Maintenance Code will provide useful provisions related to vacant buildings, such as board-up standards and maintenance of premises on private property.
BACKGROUND AND DISCUSSION
Every three years, the State Building Codes are updated and disseminated by the State. The current code is the 2022 Code, which went into effect January 1, 2023. The 2025 California Building Standards Code (California Code of Regulations Title 24), adopted and approved by the California Building Standards Commission, includes Parts 1 through 12 as follows:
Part 1 California Administrative Code
Part 2 California Building Code (Volumes 1 and 2) Part 2.5 California Residential Building Code
Part 3 California Electrical Code
Part 4 California Mechanical Code
Part 5 California Plumbing Code
Part 6 California Energy Code
Date: November 4, 2025
Subject: INTRODUCTION OF AN ORDINANCE ADOPTING BY REFERENCE, PURSUANT TO GOVERNMENT CODE SECTION 50022.2 AND CALIFORNIA CODE OF
REGULATIONS TITLE 24, THE 2025 CALIFORNIA BUILDING STANDARDS CODE, PARTS 1 THROUGH 12, AND THE 2024 INTERNATIONAL PROPERTY
MAINTENANCE CODE, AND ADOPTING LOCAL AMENDMENTS THERETO IN
ACCORDANCE WITH CALIFORNIA HEALTH AND SAFETY CODE SECTIONS 17922, 17958, 17958.5, 17958.7, AND 18941.5, AND FINDING THE ADOPTION OF SUCH
CODES AND AMENDMENTS EXEMPT FROM THE CALIFORNIA
ENVIRONMENTAL QUALITY ACT (CEQA) PURSUANT TO CEQA GUIDELINES SECTION 15061(b)(3)
Part 7 California Wildland Urban Interface Code Part 8 California Historical Building
Part 9 California Fire Code
Part 10 California Existing Building Code
Part 11 California Green Building Code
Part 12 California Reference Standards Code
The International Property Maintenance Code was updated in 2024 and is not part of the Code unless specifically adopted. In addition, the minimal local administrative amendments to the Code must be readopted.
After introduction and first reading of the ordinance, staff will complete the public noticing requirements by publishing a Notice of Public Hearing in accordance with and return on November 18, 2025, for the public hearing and adoption. Once adopted, the 2025 California Building Standards Codes and the 2024 International Property Maintenance Code will take effect on January 1, 2026.
Public Noticing
In addition to the public noticing required by state law, City Staff has posted a 2025 California Code Changes Summary and FAQs sheet regarding the new 2025 California Building Standards Code and 2024 International Property Maintenance Code with amendments on the Building Division web page and at the building counter. Additionally, copies of the Code books are available for the public to review at the Planning and Development Services Public Counter during counter hours, 8:30 AM-4:30 PM Monday through Thursday and every other Friday (excluding holidays), or by appointment. In addition, the Vallejo Weekly Newsletter will also inform the community of the upcoming changes.
FISCAL IMPACT
The cost of implementation, education and enforcement associated with the new regulations is estimated at $25,000, and is funded through the current adopted Building Division budget. This includes staff training to implement the new code, public outreach, information handouts, the purchase of Code Books, and online code subscriptions and other costs necessitated by the adoption of new codes.
ENVIRONMENTAL REVIEW
Adoption of this Ordinance is exempt from CEQA in accordance with section 15061(b)(3) of the CEQA Guidelines because it can be seen with certainty that it will not have a significant effect on the environment.
The ordinance adopts standard codes in effect pursuant to state law and set requirements for compliance. The adoption of this ordinance does not entitle new development or any changes to the physical environment.
ATTACHMENTS
1. 2025 Building Standards Code Adoption Ordinance_CAO Stamp
2. Exhibit A to Building Standards Code Ord.
Date: November 4, 2025
Subject: INTRODUCTION OF AN ORDINANCE ADOPTING BY REFERENCE, PURSUANT TO GOVERNMENT CODE SECTION 50022.2 AND CALIFORNIA CODE OF
REGULATIONS TITLE 24, THE 2025 CALIFORNIA BUILDING STANDARDS CODE, PARTS 1 THROUGH 12, AND THE 2024 INTERNATIONAL PROPERTY
MAINTENANCE CODE, AND ADOPTING LOCAL AMENDMENTS THERETO IN
ACCORDANCE WITH CALIFORNIA HEALTH AND SAFETY CODE SECTIONS 17922, 17958, 17958.5, 17958.7, AND 18941.5, AND FINDING THE ADOPTION OF SUCH
CODES AND AMENDMENTS EXEMPT FROM THE CALIFORNIA
ENVIRONMENTAL QUALITY ACT (CEQA) PURSUANT TO CEQA GUIDELINES SECTION 15061(b)(3)
CONTACT
Kristin Pollot, Planning and Development Services Director, (707) 648-4382 [email protected]
Bill Collins, Chief Building Official, (707) 648-4387
[email protected]
1 ORDINANCE NO. _____ N.C. (2d)
AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF VALLEJO ADOPTING BY REFERENCE, PURSUANT TO GOVERNMENT CODE SECTION 50022.2 AND CALIFORNIA CODE OF REGULATIONS – TITLE 24, THE 2025 CALIFORNIA BUILDING STANDARDS CODE PARTS 1 THROUGH 12 AND THE 2024
INTERNATIONAL PROPERTY MAINTENANCE CODE, AND ADOPTING LOCAL
ADMENDMENTS THERETO IN ACCORDANCE WITH CALIFORNIA HEALTH AND SAFETY CODE SECTIONS 17922, 17958, 17958.5, 17958.7, AND 18941.5, AND
FINDING THE ADOPTION OF SUCH CODES AND AMENDMENTS EXEMPT FROM
THE CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA) PURSUANT TO CEQA GUIDELINES SECTION 15061(b)(3)
THE COUNCIL OF THE CITY OF VALLEJO DOES ORDAIN AS FOLLOWS:
SECTION 1. Recitals.
A. California Health and Safety Code Sections 17922, 17958, 17958.5, 17958.7, and 18941.5 authorize local jurisdictions to adopt the California Building Standards Codes with amendments reasonably necessary because of local climatic, geological, or topographical conditions; and
B. The City Council of the City of Vallejo finds that local amendments to the 2025 California Building Standards Codes are reasonably necessary to protect the health and welfare of the citizens of Vallejo because of climatic, geological, or topographical conditions and factual findings set forth in Exhibit “A,” attached hereto and incorporated herein by reference.
SECTION 2. Vallejo Municipal Code Chapter 12.04 (Building Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.04
BUILDING CODE ADOPTED
12.04.010 California Building Code Adopted.
Subject to the particular additions, deletions and amendments hereinafter set forth in this chapter, the rules, regulations, provisions, and conditions set forth in that certain code entitled California
2 Building Code, 2025 Edition, Volumes 1 and 2, including appendices F, G, H, I, J, N, O, and P, as amended and appearing in the 2025 California Building Standards Code, California Code of Regulations Title 24, Part 2, based on the 2024 International Building Code, is hereby adopted.
One full copy of which is on file with the building official in book form and which, as so filed, is referred to, adopted and made a part hereof as fully and for all intents and purposes as though set forth herein at length, shall be and the same is established and adopted as the rules, regulations, provisions, and conditions to be observed and followed to govern the construction and maintenance of buildings and premises; to safeguard life, health, property and public welfare, providing for issuance of permits and collection of fees therefore; and providing penalties for violation of such code; and subject to said additions, deletions and amendments hereinafter set forth, shall be designated, known and referred to as the Building Code of and for the City. All conflicting ordinances are hereby repealed.
12.04.020 California Building Code Administrative Provisions Adopted.
A. The Administrative Provisions of the 2025 California Building Code contained in Division II of Chapter 1 of Part 2 of Title 24 California Code of Regulations are hereby adopted by reference pursuant to Government Code sections 50022.2 through 50022.10.
B. All of the regulations, provisions, conditions, and terms of said division, together with the appendices specifically referenced in Section 12.04.010 above, one copy of which will be on file with the building official, for use and examination by the public, are hereby referred to, adopted, and made part of this chapter as if fully set forth in this chapter.
12.04.030 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 3. Chapter 12.08 (Property Maintenance Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.08
PROPERTY MAINTENANCE CODE ADOPTED
12.08.010 – International Property Maintenance Code Adoption.
The International Property Maintenance Code, 2024 Edition, as published by the International Code Council, is hereby adopted and incorporated herein by reference, save and except such portions as are deleted, modified, or amended as set forth in the table below, “IPMC Adoption Amendments,” as the city property maintenance code. One copy of said code and amendments is on file in the office of the building official of the city of Vallejo, California, for use and examination by the public.
3 IPMC Adoption Amendments
Delete the following references: Insert the following code references:
International Building Code Current California Building Code International Existing Building Code Current California Existing Building Code International Energy Conservation Code Current California Energy Code and current California Green Building Code
International Fire Code Current California Fire Code
International Fuel Gas Code Current California Plumbing Code International Mechanical Code Current California Mechanical Code International Residential Code Current California Residential Code International Plumbing Code Current California Plumbing Code International Zoning Code Zoning Ordinance of the City of Vallejo NFPA 70 Current California Electric Code
Section 101.1 [Name of Jurisdiction] City of Vallejo
Section 103.1 [Name of Department] Building Division; Planning and Development Services Department
Section 302.4 [Height in Inches] 12 Inches
Section 304.14 [Date] to [Date] January 1, 2026 to December 31, 2028 Section 602.3 [Date] to [Date] January 1, 2026 to December 31, 2028 Section 602.4 [Date] to [Date] January 1, 2026 to December 31, 2028 Code Official or Health Official Code Enforcement Manager or designee
12.08.020 – Board of Appeals.
The Board of Appeals shall be the Code Enforcement Appeals Board as established in Chapter
2.49, superseding Section 106.1 of the International Property Maintenance Code, 2024 Edition.
SECTION 4. Chapter 12.12 (Electrical Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
4 Chapter 12.12
ELECTRICAL CODE ADOPTED
12.12.010 – Electrical Code Adoption.
The California Electrical Code, 2025 Edition, including all annex chapters except for sections
80.15 and 80.27 of annex H, as amended and appearing in the 2025 California Building Standards Code, California Code of Regulations Title 24, Part 3, based on the 2023 National Electrical Code, is hereby adopted, and incorporated herein by reference, save and except such potions as are deleted, modified, or amended; as the city electrical code. One copy of said code and amendments is on file in the office of the building official of the city of Vallejo, California, for use and examination by the public.
12.12.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 5. Chapter 12.16 (Plumbing Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.16
PLUMBING CODE ADOPTED
12.16.010 – Plumbing Code Adoption.
The California Plumbing Code, 2025 Edition, including appendices A, B, D, G, L, R, and S, as amended and appearing in the 2025 California Building Standards Code, California Code of Regulations Title 24, Part 5, based on the 2024 International Plumbing Code, is hereby adopted and incorporated herein by reference, save and except such portions as are deleted, modified, or amended; as the city plumbing code. One copy of said code and amendments is on file in the office of the building official of the city of Vallejo, California, for use and examination by the public.
12.16.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 6. Chapter 12.20 (Mechanical Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.20
MECHANICAL CODE ADOPTED
5 12.20.010 – Mechanical Code Adoption.
The California Mechanical Code, 2025 Edition, and all its appendices, as amended and appearing in the 2025 California Building Standards Code, California Code of Regulations Title 24, Part 4, based on the 2024 International Mechanical Code, is hereby adopted and incorporated herein by reference, save and except such portions as are deleted, modified, or amended; as the city mechanical code. One copy of said code and amendments is on file in the office of the building official of the city of Vallejo, California, for use and examination by the public.
12.20.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 7. Part 1 of Chapter 12.28 (Fire Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.28
I. FIRE CODE ADOPTED
12.28.010 – Fire Code Adoption.
The California Fire Code, 2025 Edition, including Chapter 1, Division 2 and sections 305, 307, 308, and all Appendices of the 2024 International Fire Code and the whole thereof as adopted by the State Fire Marshal, is adopted, referred to, and incorporated in full, as hereby amended. A copy of the California Fire Code, 2025 Edition, and the 2024 International Fire Code are on file and open to public inspection in the office of the City Clerk. This Chapter shall be known and referred to as the “Vallejo Fire Code” for the City.
12.28.020 – Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
12.28.030 – Penalties.
Persons who shall violate a provision of this code or shall fail to comply with any of the requirements thereof or who shall erect, install, alter, repair or do work in violation of the approved construction documents or directive of the fire code official, or of a permit or certificate used under provisions of this code, shall be guilty of a misdemeanor, punishable by a fine of not more than one thousand dollars or by imprisonment not exceeding six months, or by both such fine and imprisonment. Each day that a violation continues after due notice has been served shall be deemed a separate offense. The remedies set forth in this section are not exclusive, and the provisions of this chapter may be enforced pursuant to any other applicable enforcement mechanism including, but not limited to, Title 1 of this code or any other applicable remedy at law or in equity.
6 SECTION 8. Chapter 12.30 (Residential Building Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.30
RESIDENTIAL BUILDING CODE ADOPTED
12.30.010 – Residential Building Code Adoption.
The California Residential Building Code, 2025 Edition, including Appendices BB, BF, BH, BM, BO, CI, and CJ as amended and appearing in the 2025 California Building Standards Code, California Code of Regulations, Title 24, Part 2.5, based on the 2024 International Residential Code, is hereby adopted, and incorporated herein by reference, save and except such portions as are deleted, modified, or amended; as the city residential building code. One copy of said code and amendments is on file in the office of the building official of the city of Vallejo, California, for use and examination by the public.
12.30.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 9. Chapter 12.32 (Energy Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.32
ENERGY CODE ADOPTED
12.32.010 – Energy Code Adoption.
The California Energy Code, 2025 Edition, and all its appendices, as amended and appearing in the 2025 California Building Standards Code, California Code of Regulations Title 24, Part 6, is hereby adopted and incorporated herein by reference, save and except such portions as are deleted, modified, or amended as the city energy code. One copy of said code and amendments is on file in the office of the building official of the city of Vallejo, California, for use and examination by the public.
12.32.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 10. Chapter 12.44 (Historical Building Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.44
HISTORICAL BUILDING CODE ADOPTED
7 12.44.010 – Historical Building Code Adoption.
The California Historical Building Code, 2025 Edition, as amended and appearing in the 2025 California Building Standards Code, California Code of Regulations Title 24, Part 8, is hereby adopted and incorporated herein by reference, save and except such portions as are deleted, modified, or amended as the city historical building code. One copy of said code and amendments is on file in the office of the building official of the city of Vallejo, California, for use and examination by the public.
12.44.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 11. Chapter 12.48 (Existing Building Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.48
EXISTING BUILDING CODE ADOPTED
12.48.010 – Existing Building Code Adoption.
The California Existing Building Code, 2025 Edition, and all its appendices, as amended and appearing in the 2025 California Building Standards Code, California Code of Regulations Title 24, Part 10, based on the 2024 International Existing Building Code, is hereby adopted and incorporated herein by reference, save and except such portions as are deleted, modified, or amended; as the city existing building code. One copy of said code and amendments is on file in the office of the building official of the city of Vallejo, California, for use and examination by the public.
12.48.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 12. Chapter 12.50 (Green Building Code Adopted) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.50
GREEN BUILDING CODE ADOPTED
12.50.010 – Green Building Code Adoption.
The California Green Building Code, 2025 Edition, and all its appendices, as amended and appearing in the 2025 California Building Standards Code, California Code of Regulations Title 24, Part 11, is hereby adopted and incorporated herein by reference, save and except such
8 portions as are deleted, modified, or amended as the city green building code. One copy of said code and amendments is on file in the office of the building official of the city of Vallejo, California, for use and examination by the public.
12.50.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 13. Chapter 12.51 (Reference Standards Code) of Title 12 (Buildings and Construction) is hereby repealed and replaced in its entirety to read as follows:
Chapter 12.51
REFERENCE STANDARDS CODE ADOPTED
12.51.010 – Reference Standards Code Adoption.
The California Reference Standards Code, 2025 Edition, appearing in the 2025 California Buildings Standards Code, California Code of Regulations Title 24, Part 12, is hereby adopted and incorporated herein by reference as the city reference standards code. One copy of said code is on file in the office of the building official of the City of Vallejo, California, for use and examination by the public.
12.51.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 14. Chapter 12.52 (Administrative Code) of Title 12 (Buildings and Construction) is hereby added in its entirety to read as follows:
Chapter 12.52
ADMINISTRATIVE CODE ADOPTED
12.52.010 – Administrative Code Adoption.
The California Administrative Code, 2025 Edition, appearing in the 2025 California Buildings Standards Code, California Code of Regulations Title 24, Part 1, is hereby adopted and incorporated herein by reference as the city administrative code. One copy of said code is on file in the office of the building official of the City of Vallejo, California, for use and examination by the public.
12.52.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
9 SECTION 15. Chapter 12.53 (Wildland Urban Interface Code) of Title 12 (Buildings and Construction) is hereby added in its entirety to read as follows:
Chapter 12.53
WILDLAND URBAN INTERFACE CODE ADOPTED
12.53.010 – Wildland Urban Interface Code Adoption.
The California Wildland Urban Interface Code, 2025 Edition, and all appendices, appearing in the 2025 California Buildings Standards Code, California Code of Regulations Title 24, Part 7, is hereby adopted and incorporated herein by reference as the city wildland urban interface code.
One copy of said code is on file in the office of the building official of the City of Vallejo, California, for use and examination by the public.
12.53.020 Board of Appeals.
The Board of Appeals shall be the Building Standards Code Appeals Board.
SECTION 16. Environmental Review.
The City Council finds that the adoption of this ordinance is exempt from the California Environmental Quality Act (“CEQA”) pursuant to Title 14, Chapter 3 California Code of Regulations, Section 15061(b) (3) in that it can be seen with certainty that there is no possibility that the adoption of this ordinance will have a significant effect on the environment. The ordinance adopts standard codes in effect pursuant to state law and sets requirements for compliance. The adoption of this ordinance does not entitle new development or any changes to the physical environment.
SECTION 17. References in Documents and Continuing Legal Effect.
References to prior versions of any portion of the Building Standards Code or of the Vallejo Municipal Code that are amended or renumbered by this ordinance that are cited in notices issued by the City or in other documents of ongoing or continuing legal effect, including resolutions adopting or imposing fees or charges, until converted, are deemed to be references to the new counterpart portions of the Building Standards Code or amended Municipal Code sections for the purposes of notices and enforcement. The provisions adopted hereby shall not in any manner affect deposits, established fees, or other matters of record which refer to or are otherwise connected with ordinances which are specifically designated by number, code section, or otherwise, but such references shall be deemed to apply to the corresponding provisions set forth in the code sections adopted or amended hereby.
10 SECTION 18. No Effect on Enforceability.
The repeal of any sections of the Municipal Code shall not affect or impair any act done, or right vested or approved, or any proceedings, suit or prosecution had or commenced in any cause before such repeal shall take effect; but every such act, vested right, proceeding, suit, or prosecution shall remain in full force and effect for all purposes as if the applicable provisions of the Municipal Code, or part thereof, had remained in force and effect. No offense committed and no liability, penalty, or forfeiture, either civil or criminal, incurred prior to the repeal or alteration of any applicable provision of the 2022 Code, as amended, shall be discharged or affected by such repeal or alteration but prosecutions and suits for such offenses, liabilities, penalties or forfeitures shall be instituted and proceed in all respects as if the applicable provision of the 2022 Code, as amended, had not been repealed or altered.
SECTION 19. Severability.
If any section, subsection, sentence, clause, phrase, or word of this Ordinance is for any reason held to be invalid by a court of competent jurisdiction, such decision shall not affect the validity of the remaining portions of this Ordinance. The City Council hereby declares that it would have passed and adopted this Ordinance, and each and all provisions hereof, irrespective of the fact one or more provisions may be declared invalid.
SECTION 20. Effective Date.
This Ordinance shall take effect and be in full force and effect from and after thirty (30) days after its final passage.
1 EXHIBIT A
FACTUAL FINDINGS ESTABLISHING THE REASONABLE NEED FOR LOCAL AMENDMENTS TO THE 2025 BUILDING STANDARDS CODES BASED UPON
CLIMATIC, GEOLOGICAL, TOPOGRAPHICAL, AND ADMINISTRATIVE
CONDITIONS
Whereas, California Health and Safety Code sections 17922, 17958, 17958.5, and 17958.7 authorize the City to amend the 2025 California Building Standards Code as reasonably necessary because of local climatic, geological, and topographical conditions.
Section 1 of this Exhibit sets forth various findings that apply to Vallejo, explaining the factual bases and local conditions that necessitate the amendments to the various provisions of the California Building Standards Code.
Section 2 of this Exhibit explains which findings apply to which amendments.
Section 1. General Findings.
The following conditions are found within the City of Vallejo and explain why the changes to the California Building Standards Code are reasonably necessary.
A. Climatic, Geological, and Topographical Conditions
1) The City of Vallejo has 18.9 miles of marine shoreline. At any given time, there are an estimated 500 vessels moored within 10-200 feet of the Vallejo shoreline.
Portions of the shoreline, especially near vessel mooring sites, are occupied by buildings, particularly those with wood-framed structures or sidings, as well as piers and pilings that are combustible. Highly combustible dry grass, weeds and brush are common in the areas adjacent to built-up locations at or near the shoreline six to eight months of each year. The arrangement and location of natural and human-made surface features, including hills, slopes, housing developments, commercial developments, fire stations, streets, and roads, combine to limit feasible response routes for fire resources. Fires moving through steep terrain double for every 20 percent of slope increase. Erratic terrain and erratic winds can cause fires to grow in an unpredictable manner.
Precipitation ranges from 15 to 24 inches per year with an average of 20.39 inches per year. Ninety percent falls during the months of October through March and 10 percent from April through September. Typically, 0.8 percent of rainfall occurs during the fire season. This is a dry period of at least six months. Additionally, the area is subject to recurrent drought. The climatic region is prone to additional local droughts in the future.
2 Temperatures have been recorded as high as 111 degrees Fahrenheit. Average summer highs are in the 90-degree range. Prevailing winds in the area are from the south or southwest in the mornings and from the north or northwest in the afternoons.
However, winds are experienced from virtually every direction at one time or another.
Velocities are generally in the 14 miles per hour (MPH) to 23 MPH range, gusting from 25 to 35 MPH. Forty MPH winds are experienced occasionally and winds up to 55 MPH have been registered locally. During the winter half of the year, strong, dry, gusty winds from the north move through the area for several days, creating extremely dry, hazardous fire conditions.
2) Earthquakes are one of the most potentially destructive threats to life and property in the city. A moderate to severe seismic incident on any of the several fault zones located in or near the city is expected to cause extensive property damage, disruptions to communications systems, and damage to public utility systems.
3) Local climatic, geologic, and topographic conditions impact emergency response efforts, and the frequency, spread, acceleration, intensity, and size of fires which involve buildings in this community. Therefore, it is found to be reasonably necessary that the 2025 California Building Standards Code, California Code of Regulations Title 24, parts 1 through 12 and the 2024 International Property Maintenance Code be modified to mitigate the effects of the risks associated with the above conditions.
B. Administrative Regulations.
Local regulations necessary to carry out the application of the California Building Standards Code that do not establish standards may be enacted without meeting the requirements of sections 18941.5, 17958, 17958.5 and 17958.7 of the Health and Safety Code. The changes made include provisions making the Code compatible with other ordinances enforced by the City.
3 Section 2. Which Findings Apply to Which Amendments.
Amendments to the 2025 Edition of the California Building Standards Code are found reasonably necessary based on the condition cited within this Ordinance and Section 1 above as follows.
Municipal Code Section –
California Building Standard Code Provision Applicable Finding
12.04.010
Building Code Adopted, including Appendices F, G,
H, I, J, N, O, and P.
A1, A2, A3
12.04.020
Administrative Provisions Adopted B
12.04.030 (CBC 1.8.8.1; 113)
Designation of Appeals Board B
12.08.010
Property Maintenance Code Adopted, including
Amendments
A1, A2, A3
12.08.020 (IPMC 108)
Designation of Appeals Board B
12.12.010
Electrical Code Adopted, including All Annex
Chapters Except For Sections 80.15 And 80.27 Of
Annex H
A1, A2, A3
12.12.020 (CEC 89.108.8)
Designation of Appeals Board B
12.16.010
Plumbing Code Adopted, including appendices A, B,
D, G, L, R, and S.
A1, A2, A3
12.16.020 (CPC 1.8.8.1; 107.0)
Designation of Appeals Board B
12.20.010
Mechanical Code Adopted, including All Appendices. A1, A2, A3
12.20.020 (CMC 1.8.8.1; 107.0)
Designation of Appeals Board B
12.28.010
Fire Code Adopted, Including Amendments. A1, A2, A3
12.28.020 (CFC Section 111)
Designation of Appeals Board B
4 12.28.030 (CFC 112.4)
Penalties A1, A2, A3, B
12.30.010
Residential Building Code Adopted, including
Appendices BB, BF, BH, BM, BO, CI, and CJ
A1, A2, A3
12.30.020 (CRC 1.8.8.1; 112.1)
Designation of Appeals Board B
12.32.010
Energy Code Adopted, including All Appendices. A1, A2, A3
12.44.010
Historical Building Code Adopted A1, A2, A3, B
12.44.020 (CHBC 112)
Designation of Appeals Board B
12.48.010
Existing Building Code Adopted, including All
Appendices.
A1, A2, A3
12.48.020 (CEBC 112)
Designation of Appeals Board B
12.50.010
Green Building Code Adopted, including All
Appendices.
A1, A2, A3
12.51.010
Reference Standards Code Adopted A1, A2, A3, B
12.52.010
Administrative Code Adopted. A1, A2, A3, B
12.53.010
Wildland Urban Interface Code Adopted, including
All Appendices.
A1, A2, A3
CONSENT CALENDAR 8.I.
DATE: November 4, 2025
TO: Mayor and Members of the City Council
FROM: Erik Rzomp, Executive Assistant to Mayor Sorce
SUBJECT: AUTHORIZE THE COUNCIL BY MOTION TO APPROVE A PROCLAMATION HONORING C.C. SABATHIA.
RECOMMENDATION
Vallejo City Council to approve a proclamation by motion to honor Vallejo Major League Baseball Star, philanthropist and author Charles Carsten “CC” Sabathia.
REASONS FOR RECOMMENDATION
Vallejo native C.C. Sabathia has outstanding lifetime achievements in Major League Baseball, Philanthropy, and Arts & Culture and is well known locally and nationally. He and his foundation have made significant contributions to the youth of Vallejo.
BACKGROUND AND DISCUSSION
On August 5, 2025, at the Vallejo City Council meeting, the Vallejo City Council granted a Key to the City and an honorary street sign designation to honor the accomplishments of Charles Carsten “CC” Sabathia according to City Council Policy Honorary Street Sign Designation, Key to the City and Ceremonial Documents. The granting of a proclamation is an additional honor to recognize the world class athletic accomplishments of Mr. Sabathia as well as his philanthropic activities in the City of Vallejo.
CC Sabathia has outstanding achievements in sports. CC was a three-sport athlete at Vallejo High School, where he excelled in football, basketball and baseball. He received scholarship offers to play college football and baseball. He debuted in major league baseball at 20-years-old and quickly evolved into an All-Star and Cy Young Award winner before becoming the ace of a World Series winner. He was one of the most durable and effective left-handed starting pitchers in MLB. He played for three major league teams: Milwaukee, Cleveland, and New York. Sabathia’s 3,093 strikeouts ranked 16th on the all-time list at the time of his retirement, and he was just the third left-hander to join the 3,000-strikeout club. He retired as one of only five pitchers with at least 250 wins, 3,000 strikeouts and a .600 winning percentage. In 26 postseason games, Sabathia was 10-7 with 121 strikeouts in 130 innings He was elected to the National Baseball Hall of Fame as a part of the Class of 2025. He was elected on the first ballot receiving 86.8% of the vote.
CC has never forgotten his hometown of Vallejo. Throughout his very successful professional baseball career, CC and his family have looked for opportunities to give back and to support the youth and families of Vallejo.
CC, Amber, his wife and Margie, his mother established the PitCCh-In Foundation. The foundation’s focus is meeting the needs of children and families in the inner cities of New York City and Vallejo through philanthropic means along with contributions of time and presence.
The Foundation sponsors free baseball camps in Vallejo with each camper receiving balls, bats, hats, shoes along with instruction. The Vallejo High School baseball team and other professional and college athletes assist CC himself in teaching baseball skills and rules.
Date: November 4, 2025
Subject: AUTHORIZE THE COUNCIL BY MOTION TO APPROVE A PROCLAMATION HONORING C.C. SABATHIA.
The PitCCh-In Foundation sponsors many other activities which benefit the families and youth of Vallejo. The Foundation:
• Is the largest annual donor to the Vallejo Teacher Store where ALL teachers in the Vallejo City Unified School District can come and shop for FREE for school supplies. • Is an annual donor of FREE new backpacks with new school supplies inside of each new backpack. • Donated thousands of dollars in scholarships to deserving high school students throughout the Vallejo community.
• Donated new cheer and athletic uniforms and equipment to Vallejo High School and North Vallejo Little League.
• Donated COVID supplies for the schools including masks, hand sanitizers, and boxes of Kleenex and gloves to the Teacher Store.
• Donated Free Thanksgiving Turkeys through the Contra Costa – Solano County Food Bank. This event has been held in North Vallejo and is open to the entire Vallejo Community. • Donated labor and funds to update Vallejo High School Baseball Field, turned the field around, and installed a new surface sprinkler system, new fencing, seating and a scoreboard. Similar updates were also made at North Vallejo Little League which serves the youth of the Country Club Crest neighborhood.
CC Sabathia is an author and wrote his nationally bestselling memoir, “Till the End.” The book is an inspiration as CC shares his story of success and overcoming addiction.
Given CC Sabathia’s lifetime accomplishments in Major League Baseball, Philanthropy in the Vallejo Community and his contribution to Arts and Culture, he has earned the recognition from the City of Vallejo.
The proclamation will be presented to Mr. Sabathia at an event on Sunday November 16, 2025.
FISCAL IMPACT
None.
ENVIRONMENTAL REVIEW
This action is exempt from the California Environmental Quality Act (CEQA) because it is not a project which has a potential for resulting in either a direct physical change in the environment, or a reasonably foreseeable indirect physical change in the environment, pursuant to CEQA Guideline section 15378.
ATTACHMENTS
1. 11042025 Proclamation- Honoring Vallejo's Hometown Hero CC Sabathia signed and sealed
CONTACT
Erik Rzomp, Executive Assistant to Mayor Sorce (707) 648-4377 [email protected]
PROCLAMATION
HONORING CHARLES CARSTEN “CC” SABATHIA, VALLEJO’S HOMETOWN HERO WHEREAS, Carsten Charles “CC” Sabathia, a proud Vallejo native and Vallejo High School alumnus, in his first year of eligibility was inducted into the National Baseball Hall of Fame on Sunday, July 27, 2025, in Cooperstown, New York, in recognition of his remarkable achievements in Major League Baseball; and WHEREAS, CC Sabathia’s historic career includes pitching for three major league teams: the Cleveland Indians (now Guardians), Milwaukee Brewers, and New York Yankees. He recorded over 3,000 strikeouts, 251 wins, and was named the 2007 American League Cy Young Award winner and the 2009 American League Championship series MVP cementing his legacy as one of baseball’s all-time greats; and WHEREAS, despite his national acclaim, CC Sabathia has never forgotten his Vallejo roots. He has continuously demonstrated unwavering dedication to our youth and families through personal works and through his philanthropic PitCCh-In Foundation. The Foundation, co-founded with Amber, his wife, supports free annual youth baseball camps, backpack giveaways, donations to the Vallejo Teacher Store, scholarships and various other community enhancement efforts; and
WHEREAS, in recognition of his impact on and off the field, Vallejo High School in 2012 named its baseball field “CC Sabathia Field”, serving as a lasting acknowledgement to his contributions to youth, education, and sports; and WHEREAS, the City of Vallejo recognizes the extraordinary service, leadership, and pride CC Sabathia brings to our community through public service and advocacy.
NOW, THEREFORE, BE IT PROCLAIMED, that I, Andrea Sorce, Mayor of the City of Vallejo and the Vallejo City Council, do hereby proclaim S unday, November 16, 2025, as CC and Amber Sabathia Day in the City of Vallejo to honor the accomplishments, philanthropy and Vallejo pride of both Charles Carsten “CC” and Amber Sabathia. Let it be known that CC and Amber embody the spirit of Vallejo: resilient, generous, and committed to excellence.
Dated: November 16, 2025
__________________________________
ANDREA SORCE, MAYOR
Vice Mayor Peter Bregenzer, District 5
Council Member Helen-Marie Gordon, District 6
Council Member Tonia Lediju, District 3
Council Member Alexander Matias, District 1
Council Member Diosdado ‘JR’ Matulac, District 2
Council Member Charles Palmares, District 4
ACTION ITEM 9.A.
DATE: November 4, 2025
TO: Mayor and Members of the City Council
FROM: Alicia M. Jones, Housing Director
SUBJECT: ADOPT A RESOLUTION APPROVING THE ISSUANCE OF THE CALIFORNIA MUNICIPAL FINANCE AUTHORITY QUALIFIED 501(C)(3) BONDS IN AN AGGREGATE PRINCIPAL AMOUNT NOT TO EXCEED $80,000,000 FOR THE PURPOSE OF
FINANCING OR REFINANCING THE ACQUISITION, REHABILITATION, IMPROVEMENT
AND EQUIPPING OF BAY VILLAGE APARTMENTS AND CERTAIN OTHER MATTERS
RELATING THERETO
RECOMMENDATION
Adopt the resolution approving the issuance of the Bonds by the California Municipal Finance Authority (CMFA) for the benefit of Step Up Housing, a California nonprofit public benefit corporation through a special purpose entity (together, the “Borrower”), to provide for the financing of the Bay Village Apartments. Such adoption is solely for the purposes of satisfying the requirements of the federal Tax Equity and Fiscal Responsibility Act (TEFRA), the Code and the California Government Code Section 6500 (and following).
REASONS FOR RECOMMENDATION
Approval by the City Council is required in order for the CMFA to issue revenue bonds for the benefit of the borrower to finance or refinance the acquisition, rehabilitation, improvement and equipping of a multifamily rental housing project located at 1107 Porter Street, Vallejo, California, known as Bay Village Apartments. The City would have no financial liability for the bonds or the project, as described below.
BACKGROUND AND DISCUSSION
The Borrower has requested that the California Municipal Finance Authority (CMFA) issue one or more series of qualified 501(c)(3) bonds in an aggregate principal amount not to exceed $80,000,000, including, but not limited to revenue bonds issued as part of a plan to finance or refinance the acquisition, rehabilitation, improvement and equipping of a multifamily rental housing project located at 1107 Porter Street, Vallejo, California known as Bay Village Apartments. CMFA is a California Joint Powers Authority whose members are cities and other public agencies in California. CMFA is a governmental agency with the authority to issue bonds on behalf of 501(c)(3) non-profits in California. The non-profit in this case is Step Up Housing which is also the ultimate borrower of the bonds.
In order for all or a portion of the Bonds to qualify as tax-exempt bonds, the City of Vallejo must conduct a public hearing (the “TEFRA Hearing”) providing for the members of the community an opportunity to speak in favor of or against the use of tax-exempt bonds for the financing of the Project. Prior to such TEFRA Hearing, reasonable notice must be provided to the members of the community. Following the close of the TEFRA Hearing, an “applicable elected representative” of the governmental unit hosting the Project must provide its approval of the issuance of the Bonds for the financing of the Project. The TEFRA hearing was opened on October 28, 2025. A TEFRA hearing is required by Internal Revenue Code section 147(f).
TEFRA hearings are required by both the issuer of the bonds, which in this case is CMFA, as well as by the host jurisdiction of the project, which in this case is the City. The City is not approving the issuance of any bonds by the City. It is approving its support of the issuance by CMFA. The TEFRA hearing for the host
Date: November 4, 2025
Subject: ADOPT A RESOLUTION APPROVING THE ISSUANCE OF THE CALIFORNIA MUNICIPAL FINANCE AUTHORITY QUALIFIED 501(C)(3) BONDS IN AN AGGREGATE PRINCIPAL AMOUNT NOT TO EXCEED $80,000,000 FOR THE
PURPOSE OF FINANCING OR REFINANCING THE ACQUISITION,
REHABILITATION, IMPROVEMENT AND EQUIPPING OF BAY VILLAGE
APARTMENTS AND CERTAIN OTHER MATTERS RELATING THERETO
agency (the City in this case) is designed to provide the public and the City Council an opportunity to comment on the project and the issuance of the bonds by CMFA for Step Up Housing.
Approving tonight's resolution does not approve the issuance of any bonds by the City. It does approve the issuance of the bonds for the project by CMFA and Step Up Housing. The City will have no responsibility whatsoever for the bonds. There is no exposure to the City for any kind of financial damage and, as a member of the CMFA the City will receive approximately 25% of the bond fees paid to CMFA by the borrower.
This process is called fee sharing.
Step Up Housing
Step Up Housing is a California nonprofit public benefit corporation formed to (i) acquire and provide housing for low- and moderate-income persons and households and (ii) serve as general partner in limited partnerships or managing members of other entities which develop, own, and/or operate housing for the benefit of low- and moderate-income persons in need of affordable housing and related services.
The Bay Village Apartments is an existing 260-unit apartment complex located at 1107 Porter St., Vallejo, CA.
The Project is currently operating as a market-rate multifamily project. Consistent with Step Up Housing’s mission of creating and preserving safe and affordable housing for low-income households, Step Up plans to acquire the Project and convert 75% of the units to affordable housing. Step Up will maintain 25% of the units as market-rate units.
At closing, CMFA and Step Up Housing will enter into a regulatory agreement with an affordability period of 40 years. Income restriction levels will be 20% of the units at the Project (52 units) to very low-income households earning at the 50% AMI level or below and 55% of the units at the Project (143 units) to households earning 80% AMI or below, with corresponding rent restrictions. The income qualifications and rent determinations are set by the U.S. Department of Housing and Urban Development.
While the facility is in relatively good condition, the borrower plans to make a number of capital repairs and improvements to the project. The foregoing includes repairs to wooden walkways, stairs and railings, retaining wall repairs, roof repairs and replacements, landscaping improvements, window replacements, painting, and various plumbing and electrical repairs. In addition, the borrower will refurbish unit interiors as necessary as units turn over. The Borrower has reserved $5.8 million for immediate and future repairs and improvements to the Project.
The Borrower also intends to offer tenant services to the residents depending on what is most impactful or needed. Services will be decided after surveying the tenants. The Borrower’s purchase of the property and sale of the bonds is expressly conditioned upon the transaction closing in mid-November.
California Municipal Finance Authority
The CMFA was created on January 1, 2004, pursuant to a joint exercise of powers agreement to promote economic, cultural and community development, through the financing of economic development and charitable activities throughout California. To date, over 350 municipalities, including the City of Vallejo, have become members of CMFA.
The CMFA was formed to assist local governments, non-profit organizations and businesses with the issuance
Date: November 4, 2025
Subject: ADOPT A RESOLUTION APPROVING THE ISSUANCE OF THE CALIFORNIA MUNICIPAL FINANCE AUTHORITY QUALIFIED 501(C)(3) BONDS IN AN AGGREGATE PRINCIPAL AMOUNT NOT TO EXCEED $80,000,000 FOR THE
PURPOSE OF FINANCING OR REFINANCING THE ACQUISITION,
REHABILITATION, IMPROVEMENT AND EQUIPPING OF BAY VILLAGE
APARTMENTS AND CERTAIN OTHER MATTERS RELATING THERETO
of taxable and tax-exempt bonds aimed at improving the standard of living in California. The CMFA’s representatives and its Board of Directors have considerable experience in bond financing.
Previous TEFRA hearings
The City has conducted and approved TEFRA hearings in previous years to support the issuance of Bonds in the City of Vallejo through CMFA.
The most recent TEFRA hearing was held on April 23, 2024, for Klein Financial Corporation, the developer of Harbor Park Apartments Phase 2, located at 969 Porter Street, Vallejo, California. The purpose of the TEFRA hearing was to issue revenue bonds as part of a plan to finance or refinance the acquisition, construction, improvement and equipping of the multifamily rental housing project. The City has no liability for the bonds issued.
FISCAL IMPACT
The Bonds to be issued by the CMFA for the Project will be the sole responsibility of the Borrower, and the City will have no financial, legal, moral obligation, liability or responsibility for the Project or the repayment of the Bonds for the financing of the Project. All financing documents with respect to the issuance of the Bonds will contain clear disclaimers that the Bonds are not obligations of the City or the State of California but are to be paid for solely from funds provided by the Borrower.
The Board of Directors of the California Foundation for Stronger Communities, a California non-profit public benefit corporation (the “Foundation”), acts as the Board of Directors for the CMFA. Through its conduit issuance activities, the CMFA shares a portion of the issuance fees it receives with its member communities and donates a portion of these issuance fees to the Foundation for the support of local charities. With respect to the City of Vallejo, it is expected that approximately 25 percent of the bond issuance fees attributable to the City will be granted by the CMFA (bond issuer) to the general fund of the City. Such grant may be used for any lawful purpose of the City.
ENVIRONMENTAL REVIEW
This action is exempt from the California Environmental Quality Act (CEQA) because it is not a project which has a potential for resulting in either a direct physical change in the environment, or a reasonably foreseeable indirect physical change in the environment, pursuant to CEQA Guideline section 15378.
ATTACHMENTS
1. TEFRA Resolution - Bay Village Apts CAO Stamp- CC
2. TEFRA Proof of Publication - Bay Village 4144-4929-5201 1
CONTACT
Alicia M. Jones, Housing Director (707) 648-4408
[email protected]
Approved as to form:
By: for
Veronica Nebb, City Attorney
RESOLUTION NO._______________
RESOLUTION OF THE CITY COUNCIL OF THE CITY OF VALLEJO APPROVING
THE ISSUANCE OF THE CALIFORNIA MUNICIPAL FINANCE AUTHORITY QUALIFIED 501(C)(3) BONDS IN AN AGGREGATE PRINCIPAL AMOUNT NOT TO EXCEED $80,000,000 FOR THE PURPOSE OF FINANCING OR REFINANCING THE
ACQUISITION, REHABILITATION, IMPROVEMENT AND EQUIPPING OF BAY
VILLAGE APARTMENTS AND CERTAIN OTHER MATTERS RELATING THERETO WHEREAS, Step Up Housing, a California nonprofit public benefit corporation through a special purpose entity (together, the “Borrower”) has requested that the California Municipal Finance Authority (the “Authority”) adopt a plan of financing providing for the issuance of qualified 501(c)(3) bonds as defined in Section 145 of the Internal Revenue Code of 1986 (the “Code”) in one or more series issued from time to time, including bonds issued to refund such qualified 501(c)(3) bonds in one or more series from time to time, and at no time to exceed $80,000,000 in aggregate principal amount (the “Bonds”), to finance or refinance the acquisition, rehabilitation, improvement and equipping of a multifamily rental housing project located at 1107 Porter Street, Vallejo, California (the “Project”); and WHEREAS, pursuant to Section 147(f) of the Code, the issuance of the Bonds by the Authority must be approved by the City of Vallejo (the “City”) because the Project is located within the territorial limits of the City; and
WHEREAS, the City Council of the City (the “City Council”) is the elected legislative body of the City and is one of the “applicable elected representatives” required to approve the issuance of the Bonds under Section 147(f) of the Code; and WHEREAS, the Authority has requested that the City Council approve the issuance of the Bonds by the Authority in order to satisfy the public approval requirement of Section 147(f) of the Code and the requirements of Section 4 of the Joint Exercise of Powers Agreement Relating to the California Municipal Finance Authority, dated as of January 1, 2004 (the “Agreement”), among certain local agencies, including the City; and
WHEREAS, pursuant to Section 147(f) of the Code, the City Council has, following notice duly given, held a public hearing regarding the issuance of the Bonds, and now desires to approve the issuance of the Bonds by the Authority; and
WHEREAS, the public hearing was held on October 28, 2025, and an opportunity was provided for interested persons to express their views on the issuance of the Bonds and on the nature and location of the Project;
NOW, THEREFORE, BE IT RESOLVED, by the City Council of the City of Vallejo as follows:
Section 1. The foregoing recitals are true and correct.
Section 2. The City Council hereby approves the issuance of the Bonds by the Authority.
It is the purpose and intent of the City Council that this resolution constitute approval of the issuance of the Bonds by the Authority, for the purposes of (a) Section 147(f) of the Code by the applicable elected representative of the governmental unit having jurisdiction over the area in which the Project is located, in accordance with said Section 147(f) and (b) Section 4 of the Agreement.
Section 3. The issuance of the Bonds shall be subject to the approval of the Authority of all financing documents relating thereto to which the Authority is a party. The City shall have no responsibility or liability whatsoever with respect to the Bonds and is not a party to the Bond transaction other than approving this resolution.
Section 4. The adoption of this Resolution shall not obligate the City or any department thereof to (i) provide any financing to acquire or construct the Project or any refinancing of the Project; (ii) approve any application or request for or take any other action in connection with any planning approval, permit or other action necessary for the acquisition, construction, rehabilitation, installation or operation of the Project; (iii) make any contribution or advance any funds whatsoever to the Authority; or (iv) take any further action with respect to the Authority or its membership therein.
Section 5. The officers of the City are hereby authorized and directed, jointly and severally, to do any and all things and to execute and deliver any and all documents which they deem necessary or advisable in order to carry out, give effect to and comply with the terms and intent of this resolution and the financing transaction approved hereby.
Section 6. This resolution shall take effect immediately upon its adoption.
PASSED AND ADOPTED by the City Council of the City of Vallejo this October 28, 2025.
AYES:
NOES:
ABSTAIN:
ABSENT:
Attest:
By:__________________________
City Clerk
ACTION ITEM 9.B.
DATE: November 4, 2025
TO: Mayor and Members of the City Council
FROM: Jason Ta, Chief of Police
SUBJECT: CONSIDER AND MAKE A FINDING TO CONTINUE THE STATE OF LOCAL
EMERGENCY RELATING TO PUBLIC SAFETY STAFFING
RECOMMENDATION
Consider making a finding reaffirming that the conditions exist to continue the proclamation of a local emergency.
REASONS FOR RECOMMENDATION
State law requires that the Proclamation of Local Emergency be reaffirmed every 60 days. The 60th day since the last confirmation of the proclamation is November 8, 2025. City Council must reaffirm the proclamation for it to continue.
BACKGROUND AND DISCUSSION
On July 25, 2023, the City Council unanimously voted to approve a Proclamation of Local Emergency due to the critically low staffing levels at the City of Vallejo Police Department. Below is information on the current situation with Police Department staffing and whether the conditions that gave rise to the Proclamation of Local Emergency continue to exist.
When the City of Vallejo adopted a Proclamation of Local Emergency in July 2023, the Police Department staffing continued to decline. As of Aug 2023, the department had 76 sworn staff positions filled, with nine officers on disability, four officers out on injury, and one officer on FMLA, totaling 62 full-duty sworn officers. 32 full-duty officers and 5 full-duty sergeants were working patrol. This staffing level was determined to constitute a state of emergency. At that time, the Police Department collapsed some divisions, including the Traffic Division and the Detective Division, to assign more staff to patrol.
Current Staffing Levels
Total Sworn Staffing: 81
Total Disability/Injured: 2
Full-Duty Sworn Officer: 79
Number of Officers Working Patrol: 42
Field Training Program: 2
Strategies Underway to Increase Staffing
In addition to its regular attraction and retention efforts, the Police Department is working to implement new strategies to further attract and retain officers. The Police Department has entered an agreement with Allstar recruiting to increase the department's visibility towards applicants. The Police Department has also proposed a recruitment, retention, and referral program, which the City Council approved Step 2 of 2 on July 22nd.
Steps Taken to Supplement Staffing
Date: November 4, 2025
Subject: CONSIDER AND MAKE A FINDING TO CONTINUE THE STATE OF LOCAL
EMERGENCY RELATING TO PUBLIC SAFETY STAFFING
In January of 2024, the Vallejo Police Department began coordinated discussions with the Solano County Sheriff’s Office relating to several different staffing models under a contract service agreement. At that time SB1379 was being introduced by State Senator Dodd’s office to create an exemption for the retired annuitant program to assist the COV with its public safety crisis. In Sept of 2024, SB 1379 was approved by Governor Newsom. In December of 2024, the Sheriff provided the COV with a staffing projection proposal for contract services. Since then, the city council and the county board of supervisors had provided direction for the city and the county to further negotiations for contract services. All labor unions affected have been contacted to commence meet and confer obligations which have now been completed. The decision to move forward with this agreement was made by the County Board of Supervisors on September 23rd with a reduced service model than originally requested. The City of Vallejo and Solano County are now working together to put this contracted service into operation scheduled to begin January 1, 2026.
Since, July 2024, CHP has been providing additional traffic enforcement when their traffic officers have free patrol time. CHP officers have been conducting this additional presence and enforcement on Vallejo city roadways. Starting in February, the Governor authorized CHP to provide the department with additional assistance to conduct traffic enforcement campaigns addressing sideshow activity and reckless driving. These added campaigns continue to deter and disrupt reckless driving and hold the offenders accountable.
The City Manager has concluded a Request for Proposal (RFP) for uniformed unarmed security guards.
The city’s existing security company (AX9) was selected. The City Manager's office, the City Attorney's office, Public Works, and the Police Department have since finalized the security guard deployment strategies. The AX9 contract was approved by City Council at the October 14th meeting. The pilot security guards patrol routes program is slated to begin soon, with a request from City Council to explore options of increasing the number of hours/guards dedicated to this effort as soon as possible.
The Police Department is also in the process of revitalizing its community volunteer program. The department's volunteer program will be revitalized to increase community engagement, expand department capacity for non-enforcement duties, and strengthen trust between law enforcement and residents. This program is a cost-effective alternative to additional staffing, with estimated annual savings of hundreds of paid personnel hours. By reallocating non-enforcement tasks to qualified volunteers, the Police Department will preserve sworn officer time for priority calls, reduce administrative strain, and extend its public presence at community events. A phased launch to this program could begin in January 2026 and will ensure quality training, proper oversight, and sustainable growth.
The Police Department is also in the final stages of bringing forward a sex trafficking reduction proposal to City Council. The draft proposal is being worked on within the Public Safety Subcommittee to make recommendations to City Council on the implementation of this program.
The Police Department is also working to operationalize a Gun Violence Restraining Order (GVRO) program. This program is being created to supplement the department's current policy and will address how and when GVRO's will be utilized.
Emergency Conditions Remain
As stated above, on July 23, 2023, the City Council adopted a proclamation declaring a state of local emergency pursuant to Government Code Section 8550 et. seq. Pursuant to California Government Code Section 8630(c) the City Council is required to review the need for continuing the local emergency at least
Date: November 4, 2025
Subject: CONSIDER AND MAKE A FINDING TO CONTINUE THE STATE OF LOCAL
EMERGENCY RELATING TO PUBLIC SAFETY STAFFING
once every 60 days until the City Council terminates the local emergency. Council last reaffirmed the emergency at its September 9, 2025, meeting.
City staff believe that Police Department staffing remains in an emergency staffing condition as of November 2025. As such, staff believe that a state of emergency still exists and recommends that the City Council vote to reaffirm the existence of the state of local emergency.
FISCAL IMPACT
There is no immediate financial impact associated with this item. Any potential impact will be brought back to City Council with related costs.
ENVIRONMENTAL REVIEW
This action is exempt from the California Environmental Quality Act (CEQA) because it is not a project which has a potential for resulting in either a direct physical change in the environment, or a reasonably foreseeable indirect physical change in the environment, pursuant to CEQA Guideline section 15378.
ATTACHMENTS
None
CONTACT
Jason Ta, Chief of Police
(707) 648-4540
[email protected]
INFORMATIONAL ITEM 10.A.
DATE: November 4, 2025
TO: Mayor and Members of the City Council
FROM: Ivette Iraheta, Economic Development Program Manager SUBJECT: RECEIVE PRESENTATION ON THE MARE ISLAND INFRASTRUCTURE ASSESSMENT (MIIA) DRAFT REPORT AND PROVIDE INPUT FOR COMPLETION
RECOMMENDATION
The City of Vallejo (City) and Vallejo Flood and Wastewater District (VFWD) received a grant from the U.S.
Economic Development Administration (EDA) in 2021 to perform a comprehensive infrastructure assessment on Mare Island. The consultant procured for this work, West Yost & Associates, Inc. (West Yost) has produced a draft report of their findings to present to the City Council to gain feedback prior to finalizing the report. Staff recommends that City Council receive the presentation and provide feedback prior to finalizing the report.
REASONS FOR RECOMMENDATION
Staff recommends that City Council receive a presentation on the Mare Island Infrastructure Assessment (MIIA) draft report and provide feedback prior to finalizing the report.
BACKGROUND AND DISCUSSION
The City submitted a grant application in the amount of $960,000 to the U.S. Economic Development Administration (EDA) in December 2020 under the Economic Adjustment Assistance Grant Program (Program) proposing to undertake a significant and comprehensive infrastructure analysis on Mare Island for its Mare Island Infrastructure Assessment (MIIA) project. The goals of the City of Vallejo (City)/Vallejo Flood Water District aligned very well with the EDA’s grant objectives, which is to support strategic investments for economic development, foster job creation, and attract private investment in economically distressed areas of the United Sates. The City received notification from the EDA on September 7, 2021, that it had been awarded the grant in the amount of $960,000 for the project, with a requirement of a local contribution towards project cost. Mare Island Co. agreed to take part in the coordination of the MIIA project and to contribute $300,000 as a local match. City/VFWD agreed to commit $240,000 through in-kind staff time for administrative work for project implementation. This brought the initial project budget to $1.5M.
The City issued a request for qualifications (RFP) on June 17, 2022, inviting qualified firms to carry out the MIIA project scope. Three (3) RFPs were received, and the selected consultant was West Yost & Associates, Inc. (Davis, CA). The evaluation team considered West Yost to be the most qualified firm based on the following key advantages of the firm:
1. Experience conducting similar infrastructure assessment, including delivering water and sewer master plan updates for other local agencies.
2. The firm’s detailed understanding of the scope of work and flexibility
3. Resources, including staffing to complete the MIIA and deliver the technical report to City within the specified timeline
City Council approved the contract for West Yost on November 15, 2022 in the amount of $1,260,000. The
Date: November 4, 2025
Subject: RECEIVE PRESENTATION ON THE MARE ISLAND INFRASTRUCTURE ASSESSMENT (MIIA) DRAFT REPORT AND PROVIDE INPUT FOR COMPLETION
work was initiated in January 2023 with work conducted in coordination with City department staff, VFWD, and The Mare Island Co. through all phases.
This primary goal of the MIIA is to provide the City of Vallejo and Vallejo Flood and Wastewater District with a comprehensive understanding of the infrastructure improvements required to support the successful redevelopment and long-term growth of Mare Island. Reliable water, sanitary sewer, storm drainage and flood control, roads, and dry utility systems are essential for enabling new development, protecting public health and safety, and maintaining operational resilience. The MIIA identifies current system limitations, evaluates future service needs, and develops planning-level recommendations to ensure that infrastructure is not a constraint to achieving the Mare Island’s full development potential.
The assessment provides a comprehensive evaluation of the existing condition and capacity of Mare Island’s core infrastructure systems including water, sanitary sewer, storm drainage and flood control, roads, dry utilities, and geotechnical conditions and identifies the improvements needed to support both near-term and long-term development of the island.
City staff have been in communication with the EDA through the entire grant implementation period, updating the agency on the MIIA project’s progress and specifically additional funding needs. Staff and the project partners informed the EDA of additional scope of work that was essential to complete the project but was not funded with the original grant award and the local match dollars provided by Mare Island Co. Therefore, staff made a request to EDA for additional funds for the optional tasks identified by the Project team, including West Yost, the VFWD and City staff. Those additional tasks included a complete dry utility systems evaluation and coordination with the utility companies, development of a hydraulic model, flow monitoring, geotechnical evaluation and other tasks critical to fully understanding the infrastructural needs on the island.
On December 15, 2022, City staff transmitted a letter to EDA requesting the additional funds identified to complete the entire MIIA. On June 5, 2023, the City received notification from the EDA informing the City that the additional funding request had been conditionally approved. On August 28, 2023, the EDA provided official notice of the Financial Assistance Award Amendment, increasing the original grant by the full requested amount of $555,927. On September 26, 2023 City Council approved acceptance of the increase in grant award, and an amendment to the West Yost professional services contract to increase to $1,815,927, to accept and fund the additional scope of work. The West Yost consultant contract was extended by a year to implement the base contract and additional tasks.
During the approximately two years, West Yost has been conducting extensive studies and collecting data on the various infrastructure categories.
General assessment activities that have been performed are:
Land Use Planning
• Developed Near-term and Build-out land use projections and maps which were used to develop future water demands and sewer flows for capacity analyses.
Potable Water System
• Updated hydraulic model and completed model calibration using actual water meter data. • Developed existing, near-term, and build-out scenarios in hydraulic model and performed capacity and performance analysis for normal operation and fire flow scenarios. • Completed pipeline electromagnetic crown testing and ultrasonic thickness testing at 8 locations.
Date: November 4, 2025
Subject: RECEIVE PRESENTATION ON THE MARE ISLAND INFRASTRUCTURE ASSESSMENT (MIIA) DRAFT REPORT AND PROVIDE INPUT FOR COMPLETION
• Prepared pipeline testing analysis report.
• Developed infrastructure improvement recommendations to accommodate near-term and future (build- out) conditions.
• Held water system workshop to review preliminary results (November 2, 2023). • Prepared 2nd Draft Water System Chapter (submitted March 22, 2024).
Sanitary Sewer System
• Performed flow monitoring of sanitary sewer system at three locations. • Developed sanitary sewer flow estimates for use in hydraulic model based on sewer flow monitoring data.
• Developed existing, near-term, and build-out scenarios in hydraulic model and performed capacity and performance analysis for dry and wet weather conditions. • Calibrated hydraulic model.
• Completed CCTV of approximately 7,700 feet of sewer pipeline. • Performed analysis of CCTV inspections to prioritize next phase of CCTV work. • Performed field inspection and condition assessment of approximately 100 manholes and nine lift stations.
• Developed infrastructure improvement recommendations to accommodate near-term and future (build- out) conditions.
• Prepared Draft Sewer System Chapter (submitted October 11, 2024).
Storm Drain and Flood Control Systems
• Performed field inspection and condition assessment of 23 storm drain manholes and one lift station. • Developed sea level rise protections.
• Developed hydraulic and hydrodynamic model to simulate future storm and sea level rise scenarios. • Developed infrastructure improvement recommendations to accommodate future conditions. . • Held storm drain and flood control workshop to review preliminary results (January 25, 2024). • Prepared Draft Storm Drain Chapter (submitted June 13, 2024).
Geotechnical
• Reviewed background information – previous studies and publicly available information. • Held geotechnical workshop to review preliminary results (January 25, 2024). • Prepared Draft Geotechnical System Chapter (submitted March 13, 2024). • Performed reconnaissance-level inspection of Mare Island Sea Wall.
Roads
• Performed inspection and testing of all Mare Island roadways. • Developed rehabilitation plans for roadways in poor condition. • Held roads workshop to review preliminary results (February 13, 2024). • Prepared Draft Roads System Chapter (submitted January 29, 2024).
Date: November 4, 2025
Subject: RECEIVE PRESENTATION ON THE MARE ISLAND INFRASTRUCTURE ASSESSMENT (MIIA) DRAFT REPORT AND PROVIDE INPUT FOR COMPLETION
Dry Utilities
• Received records, information, and mapping from all utility companies. • Discussed with utility company considerations for expansion of dry utility systems. • Prepared Draft Dry Utility Systems Chapter (submitted December 14, 2023).
The preliminary data gathered by early 2024 identified the following:
1. Water system fire flow evaluations have identified existing and future deficiencies which will require improvement projects.
2. Water pipeline testing has identified that corrosion of pipelines is not severe, but that these pipelines should not be expected to serve the island reliably for the long-term.
3. Investigations into sewer flow monitoring data will help to identify high infiltration and inflow locations, which can be addressed through improvement projects.
4. Sea level rise protection solutions provide an option for protecting existing and future business and residents of Mare Island from flooding and allowing the businesses to continue operations in the future.
5. Several options to rehabilitate the existing sea wall have been developed including recommendations on future assessments/studies to confirm the viability of utilizing the existing sea wall.
6. Dry utility company expansion plans and existing mapping will provide a basis for understanding the dry utility needs of future development.
7. Road rehabilitation plans provide improvement projects and timing to bring roads to an acceptable condition for existing and future development.
8. Geotechnical information for all of Mare Island is now consolidated in one report for future reference.
A public information meeting was conducted on September 4, 2024 inviting residents, Mare Island commercial tenants, and other stakeholders to receive a presentation from West Yost on the preliminary findings. About 40 residents attended the presentation and listened to West Yost provide background on the methodology used to conduct the assessment and information about the findings on the various infrastructure.
Since evaluating the preliminary findings, obtaining input from City and VFWD staff, the Mare Island Co. and from the stakeholder presentation, West Yost updated each of the chapters and provided a comprehensive draft report in July 2025.
The draft report includes a dedicated chapter for each discipline, with an introduction and recommendations chapters, as follows:
Chapter 1 - Introduction
Chapter 2 – Land Use
Chapter 3 – Water System
Chapter 4 – Storm Drainage and Flood Control System
Chapter 5 – Sanitary Sewer System
Chapter 6 – Geotechnical Evaluation (including sea wall) Chapter 7 – Roads System
Chapter 8 – Dry Utility Systems
Chapter 9 – Integrated Recommendations
Date: November 4, 2025
Subject: RECEIVE PRESENTATION ON THE MARE ISLAND INFRASTRUCTURE ASSESSMENT (MIIA) DRAFT REPORT AND PROVIDE INPUT FOR COMPLETION
The MIIA builds upon prior studies completed since the adoption of the Mare Island Reuse Plan in 1994. At project outset, the team compiled and reviewed available data including prior infrastructure reports, geotechnical studies, as-built drawings, and GIS mapping to inform current analyses and avoid duplication of efforts. The MIIA evaluates infrastructure systems under two planning scenarios:
• Existing/Near-Term Scenario (through 2027) – Represents known development and infrastructure needs based on current land use and projects in progress. • Build-Out Scenario (through 2063) – Represents full redevelopment of the island based on long-range planning assumptions and growth forecasts.
Each infrastructure system was evaluated using a consistent methodology; where applicable, field investigations, condition assessments, flow monitoring, and modeling were conducted to support analyses.
Recommendations were developed for each system and land use scenario, with a focus on coordination between systems to reduce rework, minimize disruptions, and support resilient, phased implementation.
Summary of Key findings and recommendations include:
Water System:
• Over 60% of Mare Island's water pipelines are more than 100 years old, and many are in unknown or poor condition.
• Fire flow and pressure deficiencies are present in multiple areas, especially near the water tank and in the island’s southern section.
• Near-term recommendations include replacing 20,800 feet of pipeline, improving fire hydrant spacing, and repairing the water tank and associated fittings.
• Build-out recommendations include replacing 127,000 feet of pipeline and continuing regular condition assessments of the tank every 10 years.
Storm Drainage and Flood Control System:
● Most storm drainpipes do not meet current engineering standards and were not designed for future sea level rise conditions.
• Sea level rise is projected to increase by 3.5-feet by 2070 and 7-feet by 2100, necessitating long-term planning and shoreline protection measures.
• The existing Lift Station 15 is in poor condition and no longer serves Mare Island; coordination with Caltrans is recommended for its replacement.
• Storm drainage improvements are recommended for infrastructure areas below 10 feet elevation in the near term, with full island-wide upgrades planned through build-out.
Sanitary Sewer System:
• Smoke testing and CCTV inspections revealed significant inflow and infiltration (I&I), along with severe defects in both pipelines and manholes.
• DOM4 lift station capacity is limited to 3.9 mgd due to treatment plant constraints, making I&I reduction the most viable near-term strategy.
• Near-term recommendations include eliminating 14 severe defects, replacing over 1,400 feet of failed pipe segments, and upgrading Priority 1 lift stations.
Date: November 4, 2025
Subject: RECEIVE PRESENTATION ON THE MARE ISLAND INFRASTRUCTURE ASSESSMENT (MIIA) DRAFT REPORT AND PROVIDE INPUT FOR COMPLETION
• Build-out recommendations include expanded preventive maintenance, full lift station replacement as needed, and reevaluation of system capacity after rehabilitation.
Geotechnical and Sea Wall:
• Areas north of G Street and along San Pablo Bay are subject to long-term settlement due to thick Young Bay Mud deposits.
• Liquefaction risk is generally low in planned development zones, but lateral spreading remains a hazard.
• The existing sea wall, first built in the 1920s, is in varying condition, with ratings from “Poor” to “Satisfactory” and several observed structural defects. • Two sinkholes were documented near Dry Dock 2. Further investigation, structural retrofits, and sea level rise adaptation strategies are recommended.
Roads System:
• Pavement condition index (PCI) varies widely: newer roads score 76, while older roads in the south average 49. The citywide average is 48.
• Engineering evaluations identified appropriate treatments ranging from slurry seals to full-depth reconstruction.
• Near-term goals include completing surface seal treatments within 2–3 years and heavier rehabilitation projects within 3–5 years.
• Coordination of road repairs with other utility upgrades is recommended to avoid rework and minimize disruption.
Dry Utility Systems:
• Dry utility systems south of G Street are generally functional and expandable, while systems north of G Street are limited or non-existent.
• Utility infrastructure installed after the Navy’s departure is newer, though future systems must consider sea level rise impacts.
A recommendations (Chapter 9) provides a cross-system infrastructure strategy that brings together recommendations from all utility systems. The goal is to guide phased, coordinated, infrastructure improvements that support Mare Island’s long-term redevelopment under both near-term (through 2027) and build-out (through 2063) scenarios. An interactive WebMap tool (https://arcg.is/0jyaei3) was developed to allow users to explore recommended improvements across Mare Island in a geospatial context.
The final MIIA technical report will incorporate feedback received from City Council and VFWD Board. Once final report is produced and is accepted by City/VFWD staff as complete, it will be shared with other internal departments, and made available to the public[AG1] , including current and prospective developers on Mare Island.
Next steps:
• Use MIIA findings to support regulatory processes, including CEQA/NEPA environmental review and Mare Island Specific Plan (MISP) implementation.
Date: November 4, 2025
Subject: RECEIVE PRESENTATION ON THE MARE ISLAND INFRASTRUCTURE ASSESSMENT (MIIA) DRAFT REPORT AND PROVIDE INPUT FOR COMPLETION
• Prioritize and initiate near-term infrastructure improvements needed to enable upcoming development projects.
• Align capital projects with development phasing, ensuring utility and roadway improvements are completed ahead of site construction.
• Pursue additional grant funding for high-priority needs such as sea wall rehabilitation, sanitary sewer inspection and upgrades, and stormwater improvements.
• Use the MIIA WebMap tool to coordinate infrastructure investments across systems, track project timing by area, and support interagency collaboration.
To read the entire MIIA draft report go to: https://vallejo.hosted-by-files.com/Large- Files/MIIA%20Report%20%7C%20City%20of%20Vallejo/
FISCAL IMPACT
This is an informational item with no cost impact to the general fund or grant fund budgets.
ENVIRONMENTAL REVIEW
This action is exempt from the California Environmental Quality Act (CEQA) because it is not a project which has a potential for resulting in either a direct physical change in the environment, or a reasonably foreseeable indirect physical change in the environment, pursuant to CEQA Guideline section 15378.
ATTACHMENTS
1. MIIA Report Executive Summary_Final
CONTACT
Gillian Haen, Assistant City Manager/Interim Economic Development Director [email protected]
PREPARED BY
Mare Island Infrastructure Assessment
PREPARED FOR
City of Vallejo
and
Vallejo Flood & Wastewater District
FINAL REPORT | OCTOB
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July 2025 Draft
Executive Summary
MARE ISLAND INFRASTRUCTURE ASSESSMENT REPORT
The
Mare Island
Infrastructure Assessment (MIIA)
was
completed
for the
City of Vallejo
(City)
and the
Vallejo Flood and Wastewater District (District)
to support infrastructure planning and coordinated
re
development across Mare Island
(Island)
. The assessment provides a comprehensive evaluation of the existing condition and capacity of Mare Island’s core infrastructure systems
including water, sanitary
sewer, storm drainage and flood control, roads, dry utilities, and geotechnical conditions
and identifies
the improvements needed to support both near
-
term and long
-
term
development of the island.
The project was initiated in
January 2023
and completed in
November
2025
, with work conducted in close
coordination with the City, District, and
Mare Island Company.
INTRODUCTION (CHAPTER 1)
Mare Island has evolved from a historic U.S. naval shipyard into a growing residential, commercial,
institutional, and industrial community within the City . Following the Navy’s decommissioning of the
shipyard in 1996, the City and District assumed responsibility
over time
for the
I
sland’s water, sanitary
sewer, storm drainage, flood control, and road systems. In 2004, Mare Island was opened for
public
access
and
a decades
-
long process of redevelopment
was ini
tiated
. Today, the City partners with
Mare Island
Company to guide the
I
sland’s
redevelopment
.
The MIIA builds upon prior studies completed since the adoption of the Mare Island Reuse Plan
in 1994.
At project outset, the team compiled and reviewed available data including prior infrastructure reports, geotechnical studies, as
-
built drawings, and GIS mapping to inform current analyses and avoid duplication of efforts.
The MIIA evaluates infrastructure
systems
under two planning scenarios:
Existing/Near
-
Term Scenario
(through 2027)
–
Represents known
development and
infrastructure needs based on current land use and projects in progress.
Build
-
Out Scenario
(through 2063)
–
Represents full redevelopment of the island based on
long
-
range planning assumptions and growth forecasts.
Each infrastructure system was evaluated using a consistent methodolog y
; w
here applicable, field
investigations
, condition assessments,
flow monitoring, and modeling were conducted to support analyses.
R
ecommendations were developed for each system and
land use
scenario, with a focus on
coordination between systems to reduce rework, minimize disruptions, and support resilient, phased
implementation.
The MIIA findings are presented
in
nine
chapters
, as listed below:
Chapter 1
–
Introduction
Chapter 2
–
Land Use
Chapter 3
–
Water System
Chapter 4
–
Storm Drainage and Flood Control System
Chapter 5
–
Sanitary Sewer System
Chapter 6
–
Geotechnical Evaluation
(including the Sea
w
all)
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Chapter 7
–
Roads System
Chapter 8
–
Dry Utility Systems
Chapter 9
–
Integrated
Recommendations
For each land use scenario (existing/near
-
term and build
-
out), the MIIA identifies current system
limitations, evaluates future service needs, and provides planning -
level recommendations to ensure that
infrastructure is not a constraint to achieving the
I
sland’s full development potential.
T
he report enables
the City, District, and their partners to plan proactively, align capital investments, and support phased, coordinated redevelopment.
The remai
ning sections of this
Executive Summary
summarize the
key tasks, findings, and
recommendations presented in each chapter
of the
report
.
LAND USE (CHAPTER 2)
Future growth for Mare Island was established in the context of two land use scenarios: a n
existing/near
-
term scenario
,
which represents development on the island through 2027 , and a build
-
out
scenario, which represent
s expected
development on the island through 2063.
Land use projections were
developed in coordination with the City
, District,
and Mare Island Company, with input from key
stakeholders and large utility users including
Touro University
,
Mare Island Dry Docks
, and
Lind Marine
.
In the
existing/near
-
term scenario
, major development includes the
Connolly Street Corridor project
,
activation of
Dry Dock 1
at Mare Island Dry Docks, and a
15 -
percent
operational expansion at Lind Marine
.
The
build
-
out scenario
was based on a
preliminary draft plan of the Mare Island build
-
out land use (Mare
Island Company, February 2023), a
60 -
percent
increase in enrollment at Touro University
,
and an
additional
15 -
percent
growth at Mare Island Dry Docks
beyond near
-
term levels.
This land use framework was used to estimate utility demands, evaluate infrastructure capacity, and size recommended improvements across the water, sewer,
and
storm
drainage
systems.
WATER SYSTEM
(CHAPTER 3)
The existing
Mare Island
water system consists of 35.4 miles of transmission and distribution pipelines (ranging from 2
-
inch to 24
-
inch) and one water tank. Water service is provided to the island th r
ough three
transmission pipelines crossing Mare Island Strait
–
two in the north and one in the south.
The water system evaluation included: collecting and reviewing existing documents and mapping; identifying proposed design criteria and preferences to be used in development of infrastructure improvements; developing a hydraulic model to evaluate the system capacity, performance, and proposed
infrastructure improvements; performing condition assessment of select water system pipelines; performing a seismic and condition assessment of the water tank; and developing an integrated set of
recommendations for the existing/near
-
term and build
-
out scenarios.
Based on available age information, approximately
73 percent of the pipelines are more than 75 years
old,
and 60 percent of the pipelines are more than 100 years old. Condition information for the pipelines is largely unavailable, so age and industry standard useful life values were used to estimate pipeline condition. Physical condition
testing
to estimate wall thickness loss was performed in the field for eight metallic pipelines.
Three of the
eight
sites had calculated thickness loss that is considered negligible
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(within manufacturing tolerance)
.
The remaining
five sites
exhibited moderate to significant wall loss
(ranging
from 13 to
26 percent
)
.
Due to the lack of record information (resulting in unknown pipe age and material)
,
in addition to varying soil and groundwater conditions, it is likely that the conditions of pipe will differ in other locations of the system.
Thus, the age
-
based condition assessment results were not
modified based on field testing results.
The water tank condition assessment included visual inspection of the tank exterior and diving of the tank interior. A desktop seismic assessment was performed. Based on the assessments, the tank is in overall good condition, with the isolated areas of mod
erate surface damage (spalling and staining) on tank walls, and minor to moderate corrosion on interior pipe fittings. The seismic assessment concluded that the maximum allowable water level in the tank should be limited to 7 feet below the roof soffit to maintain
structural integrity during and after a seismic event.
Due to current operating conditions, the tank water
level already remains more than 7 feet below the roof soffit.
The
hydraulic capacity and performance evaluation
included development of water demands for the
existing, near
-
term, and build
-
out land use scenarios and evaluation of pressure and fire flow availability for each of those scenarios. The City’s existing performance and operational criteria were used to ide ntify
deficiencies and recommended improvements.
The existing condition and near
-
term scenarios showed pressures below City criteria around the Mare Island tank. These pressure issues are known to the City .
The near
-
term scenario identified fire flow deficiencies and associated pipeline improvements around the Connolly Street Corridor development.
The build
-
out scenario identified pressures below City criteria around the Mare Island tank and along the south end of the island near Ribeiro Road. The build -
out scenario identified
fire flow deficiencies across the island
and
was used to develop
associated
pipeline
improvements.
A hydraulic evaluation was performed on the three Mare Island Strait crossing pipelines
for the near
-
term
scenario. Assuming the two old crossings are not in service, operation with only one crossing does not affect the system ability to meet demands under normal operating conditions. Under fire flow conditions, available fire flow is reduce
d and some hydrants fall below minimum requirements. Replacement of the south crossing would provide a long term, reliable, redundant water connection for Mare Island.
Water System
Recommendations
Based on the assessments and evaluations performed on the water system, an integrated set of recommendations
for each land use scenario
was developed
.
All new infrastructure should meet City of
Vallejo design standards.
Existing/Near
-
term (by 2027)
recommendations include:
Replace 20,826 feet of pipeline, including the south transmission pipeline crossing to address capacity and condition deficiencies. Replace associated valves and hydrants as pipelines are replaced.
Review existing hydrant spacing and locations to meet Fire Marshal specifications.
Review existing valve spacing to provide operational flexibility.
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For the tank, repair delamination and corrosion of exterior, replace inlet pipe flap valve flange and overflow pipe flange, replace all interior piping fittings with stainless steel fittings and recoat/re
-
touch up interior piping coating.
Build
-
Out (by 2063)
recommendations include:
Install or replace 126,936 feet of pipeline
to address capacity and condition deficiencies.
Replacements should be prioritized based on leak/break history, and pipelines critical to the system (transmission mains and pipelines providing looping and redundancy).
For the tank, perform a condition assessment every 10 years and implement recommended
improvements.
STORM DRAINAGE AND FLOOD CONTROL SYSTEM
(CHAPTER 4)
Mare Island’s s
torm drainage and flood protection
is
provided through a network of
34.6 miles of
gravity
pipelines and one lift station (Lift Station 15) which convey storm water generally from the west/central part of the
I
sland
(interior)
to the east, discharging via storm drain outlets to the Mare Island Strait. A sea
wall exists on
much
of the eastern edge of the
i
sland bordering Mare Island Strait. The purpose of the
sea
wall is to separate land and
water areas, limiting damage due to wave action and
storm surge, while
also providing locations for ships to berth.
The
storm drainage and flood protection
system evaluation included: c
ollecting and reviewing existing
documents and mappin
g; identifying
proposed design criteria and preferences to be used in development of infrastructure
improvements
; d
eveloping a hydraulic
and
hydrodynamic model to evaluate the capacity
needs of the proposed
infrastructure improvements
; p
erforming condition assessment of Lift
Station 15
and select
structures (maintenance holes and inlets); and d
eveloping an integrated set of
recommendatio
ns for the existing/near
-
term and build
-
out
scenarios.
The
majority of existing
storm drainage
pipe
lines
do not meet current
District
engineering standards for
pipe coverage,
slope, or minimum pipe size.
Previous studies performed by the District
concluded that
existing infrastructure mostly lacked adequate capacity and recommended
nearly full replacement
;
additionally, the previous stud
ies
did not address sea level
rise, which further necessitates upgrades to
the storm drain and flood control infrastructure. For these
reasons, detailed condition assessment
(ag
e
-
based or other methods)
of the existing storm drain and flood control
system was not performed
as
part of this project
.
Existing District planning and design documents, along with local, state, and national best -
available
guidance documents on sea level rise were reviewed to determine future sea level rise (SLR) projections for Mare Island. Three industry standard projectio
ns for SLR were established:
Current:
S
ea level at 10 feet (based on
current FEMA Flood Insurance Rate Maps
, and
considering the 100
-
year
tide, storm surge, and riverine flow
)
Year 2070:
S
ea
level
at
13.5 feet (3.5 feet of increase
)
Year 2100:
S
ea level at
17.0 feet (7.0 feet of increase)
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Some areas of Mare Island (mostly undeveloped areas in the north and west) are currently below 10 feet elevation. The infrastructure needed for SLR does not need to be constructed immediately, but current and future infrastructure planning and designs do n
eed to address and accommodate the required future
SLR infrastructure.
The hydraulic capacity evaluation included development of a hydrauli
c and
hydrodynamic
model to
simulate storm and drainage conditions and
develop recommended infrastructure to serve the
I
sland for
future stormwater and sea level rise conditions (to Year 2100, or 17.0 feet sea level elevation). The I
sland
was divided into 12 Improvement Areas (IA
s
) based on similar features and infrastructure needs. For each area,
i
nfrastructure
improvements
were developed which included a combination of
new storm drains,
lift stations,
soil
fill, detention storage, and sea
walls
.
C
ursory c
ondition assessment included inspection of 23 storm drain maintenance holes and drain inlets, which indicated that 16
out of 24 would require replacement to meet current standards. Visual assessment of Lift Station 15 indicates the facility is in moderate to severely compromised condition and is not reliable.
LS
-
15 currently provides drainage and flood protection to the Highway 37 interchange ,
the
surrounding undeveloped, low
-
lying areas of North Mare Island
, and portions of the Alco and EPS
properties
. All
other
buildings and structures in areas of North Mare Island previously serviced by LS -
15 have been demolished or decommissioned.
Storm Drainage and Flood Control System Recommendations
Based on the assessments and evaluations performed on the storm drainage and flood control system, an
integrated set of recommendations was developed
for each land use scenario
and sea level rise
projections. All new infrastructure should meet District design standards.
Existing/Near
-
term (by 2027)
recommendations include
:
T
he primary
use of
LS
-
15 is to serve the Highway 37 interchange. LS
-
15 will
not
be
required
to serve Mare Island in the future.
Therefore,
it is recommended that coordination with
Caltrans should be implemented to advise them that (1) LS -
15 is
moderately to severely
compromised
and
not reliable, (2)
The primary purpose of LS
-
15 to serve the Highway 37
interchange
and
LS
-
15 will
not
be
required to serve Mare Island in the future
, and (3)
Caltrans should design and construct their own
lift
station in their right
-
of
-
way.
Evaluate the sea
wall and develop a strategy to provide
protection for the 2100 water level
of 17.0 feet.
Perform visual inspections of all
maintenance holes and inlets. Replace
those
constructed of
non
-
standard materials
(e.g., brick, corrugated metal)
in system areas not scheduled for
demolition or rerouting
.
P
erform visual inspection
(via maintenance holes
or CCTV
) to identify
corrugated metal
pipelines.
Prioritize replacement of corrugated
metal pipelines.
Implement infrastructure improvements to developed areas below an elevation of 10 feet in Infrastructure Areas 3, 4, 5, 7, 8, 9, 10,
and
11.
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Build
-
Out (by 2063)
recommendations include
:
Implement infrastructure improvements in all Infrastructure Areas as development occurs (if currently
undeveloped
) and to meet 2100 sea levels (17.0 feet).
It should be noted that th
e design criteria used to develop the infrastructure
improvements
for both
scenarios
are based
on guidelines that are regularly changing (e.g., the State of California Sea Level Rise Guidance document
and
District Engineering Standards including rainfall design storm data) . As the
scientific understanding of the impacts of climate change are further refined in the future,
it is expected
that international, federal, State, and local agencies will continue to provide updates on
c
lima
te and sea
level rise trends, which will in turn be used to update guidance documents.
D
evelopment of future
solutions to
address storm drainage and sea level rise on Mare Island should be based on the most current and
best available science at the time any specific project is designed and constructed. While this report
emphasizes capital improvements, solutions should be integrated with site -
specific and community
-
level
adaptation planning, regional and cross
-
jurisdictional collaboration, and consider the
site
-
specific land
uses and unique characteristics of Mare Island. Also, at the time any specific project is designed and
constructed, the design should include vulnerability assessments and adaptation strategies based on the
proposed land use.
SANITARY SEWER SYSTEM (CHAPTER 5)
Mare Island’s
s
anitary sewer
system consists of
network of
22. 6 miles of
gravity pipelines, maintenance
holes, nine lift stations, and force mains which convey wastewater generally from the south and north ends of the
I
sland to the DOM
4 (domestic) lift station. Wastewater is pumped off the island by the DOM4 lift station through a force main that runs
below the Mare Island Strait/
north of the
Napa River Causeway
and connects to the mainland trunk sewer system. On the mainland, the District’s north interceptor
trunk
sewer
connects to the Ryder Street wastewater treatment plant
(WWTP)
.
The
sewer
system evaluation included: collecting and reviewing existing documents and mapping; condition assessment of select sanitary sewer system pipelines, manholes, and lift stations; developing a hydraulic model to evaluate the capacity needs of the proposed in frastructure improvements;
and
d
eveloping an integrated set of recommendations for the existing/near -
term and build
-
out
scenarios.
Closed
-
circuit television (CCTV) inspection was performed on 70 sewer segments which indicate that
11 segments have severe structural defects (1,463 feet). Visual condition assessment was performed on 120
maintenance
holes which indicate that 102 maintenance holes have at least one component that is defective.
Smoke testing was performed on all areas of the island with known sanitary sewer systems (active or otherwise), which identified 14 severe and 44 other defects in the system. Defects in pipelines and maintenance holes, and connections to other parts of the
system contribute to inflow and infiltration
(I&I),
that
reduces capacity available for the intended sanitary sewer flows.
Visual condition assessment was performed in the field for the nine active domestic sewer lift stations on Mare Island: DOM2, DOM3, DOM4, DOM6, DOM7, DOM8, DOM11, DOM13, and the L Street lift station.
Improvement recommendations were developed based on obs erved condition and defects and were
grouped into three categories: Priority 1 which are critical to current operation; Priority 2 for continued operation beyond 2027; and Build
-
out which are expected between 2027 and 2063.
Six
of the DOMs
require improvements which are critical to current operation. It is expected that all DOMs will require full replacement or rehabilitation before 2063. All facilities have space available on -
site for future expansion.
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Flow monitoring was performed for a total of ten weeks, which was used to establish a baseline for sanitary sewer flows at each monitoring site, measure peak flow characteristics, isolate and analyze I&I, and monitor the level and pumping cycles at DOM4.
I&I analysis estimated
existing
I&I rates ranging from
6,300
gallons per day (gpd) per acre to
17,700
gpd per acre for the three flow monitoring basins.
For reference, the District
I&I
allowance for pipes built
pre
-
1 970 is 4,000 gpd per acre.
For pipelines built 1970 and later,
the I&I allowance is 600 gpd per acre.
I&I was estimated to represent up to 85 percent of
peak flows.
The
hydraulic capacity evaluation
included development of sewer flows for the existing, near -
term, and
build
-
out land use scenarios. Data from flow monitoring and historical DOM pumping records were used to calibrate the model. The calibrated hydraulic model was used to simulate the 5 -
year
, 24
-
hour peak wet
weather flow (PWWF) conditions in the existing, near
-
term (2027), and build
-
out (2063) systems. The
District’s existing design and performance criteria were used as a basis to identify deficiencies and r
ecommended improvements.
The DOM4 lift station is
flow
-
limited to 3.9 mgd due to downstream capacity constraints
in
the collection system and
at the District’s W
W
TP
. Expansion of DOM4 capacity is not viable
in the near term due to the WWTP’s physical and regulatory constraints, including the need for a new NPDES permit, major process upgrades, and limited available land.
For these reasons,
approaches to address capacity deficiencies focused primarily on reducing I&I to
reduce
unnecessary wet weather loading and preserve available capacity for future development.
This I&I reduction strategy is also consistent with State Water Resources Control Board guidance, which discourages the conveyance of non -
wastewater
flows to treatment facilities.
Although expansion of the WWTP is not feasible at this time, it may need to be reconsidered as part of long
-
term planning to address future capacity needs
.
Sanitary Sewer System Recommendations
Based on the assessments and evaluations performed on the sanitary sewer system, an integrated set of recommendations
for each land use scenario
was developed. All new infrastructure should meet District design standards.
Existing/Near
-
term (by 2027)
recommendations include:
Eliminate severe inflow defects and cross connections to the sanitary sewer identified in smoke testing
(1
4 severe defects and 4 cross connections)
. Addressing these defects and
cross connections will provide the greatest reduction in I&I at the lowest cost.
Replace or rehabilitate pipelines that were identified to have Grade 4 or 5 structural defects (
11 pipelines
;
1 ,
463 feet
). Rehabilitate maintenance holes
in
-
line or
adjacent to pipelines
that are replaced or rehabilitated.
Replace
all
brick pipelines (437 feet
identified
) and maintenance holes (18
identified
).
Rehabilitate maintenance holes with broken, cracked, or defective components (27
identified).
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Implement lift station Priority 1 improvement
recommendations (DOM 2, 4, 6, 7, 8,
L
-
Street).
Complete condition assessment on all pipelines greater than 60 years old that were not inspected as part of this project
–
approximately 13.7 miles
. Visually assess associated
maintenance holes concurrently. Address severe defects as they are identified.
Regarding capacity,
is expected
that the
i
mplementation of pipeline rehabilitation, defect
elimination, and cross
-
connection removals
will result
in measurable
I&I
reduction, helping
to alleviate capacity constraints in the system.
According to a
necdotal information
provided by the District and Mare Island Company
, no
above
-
ground overflows
have occurred
on Mare Island in recent years. As development
progresses,
reductions in I&I from near
-
term improvements are anticipated to offset flow
increases from new connections, thereby minimizing the risk of overflows
.
Once near
-
term rehabilitation and inflow elimination projects are complete, system capacity
should be re
-
evaluated using updated flow monitoring data and development -
based flow
projections. This will establish a meaningful post
-
rehabilitation baseline and inform whether
further
improvements
are necessary.
Build
-
Out (by 2063)
recommendations include:
Replace
or rehabilitate pipelines that were identified to have Grade 3 structural defects
(14
pipelines, 3,134 feet)
as part of this project (recommended within 5 years
–
by 2029
or
earlier), and pipes that were inspected after this project was concluded.
Implement a regular preventative maintenance program, including pipeline cleaning and condition assessment. Perform condition assessment of all pipes every 7 years (minimum) to identify structural and maintenance deficiencies.
For continued lift station operation beyond 2027, implement lift station Priority
2 improvement recommendations (DOM 2, 3, 4, 6, 7, 8).
Future upgrades or replacement may
be needed by 2063 depending on performance, regulatory changes, or capacity needs.
Preliminary evaluation indicates adequate space exists at all lift station sites for expansion.
Regarding capacity,
i
t is
expected
that c
ontinued pipeline rehabilitation and replacement
throughout the build
-
out period
will
result in significant reductions in I&I, further relieving capacity constraints in the system and supporting long
-
term development.
System capacity should be re
-
evaluated following completion of major rehabilitation efforts using
updated flow monitoring and development
-
based flow projections. This re
-
evaluation
will provide
a critical baseline for determining whether additional capacity improvements –
such as increasing
the DOM4 flow limit
–
are warranted.
If a formal capacity re
-
evaluation is not conducted, one of the alternative improvement approaches outlined in Section 5.7.10 should be implemented. These range from continued I&I reduction efforts to increasing
the
DOM4
flow limit
.
The following
ongoing
actions
are recommended and
will support future decision
-
making
regarding capacity upgrades or targeted system rehabilitation:
—
Monitor surcharging at key maintenance holes to identify persistent or worsening capacity deficiencies. These observations can help prioritize additional targeted rehabilitation or system improvements.
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—
Evaluate downstream impacts if DOM4 capacity is increased. Upgrades to the wastewater WWTP may be necessary, including revised permitting, physical expansion of treatment processes, and compliance with applicable regulatory and effluent quality
r
equirements.
GEOTECHNICAL EVALUATION (CHAPTER 6)
A
study of available information
was performed to evaluate the existing geotechnical conditions and considerations on Mare Island. Available information collected and reviewed included: e xisting
geotechnical
reports;
subsurface data
; h
istorical aerial imagery
; and
published geotechnical documents
from government agencies, including but not limited to historical topographic, soil and geologic, liquefaction susceptibility and landslide maps
.
Collected
information
is
presented in Appendix 6A.
Based on available information and conclusions from previous geotechnical reports, the following summary statements can be made:
The
majority of
previous subsurface investigations and studies are located in the area north of G Street and east of Azuar Drive.
Consolidation settlement is one of the major issues for the area north of G Street and east of
Azuar Drive, and west of Tisdale Avenue along San Pablo Bay due to a thick layer of Young Bay Mud (YBM).
Based on estimates developed as part of this study, c
onsolidation settlement due to
compression of the YBM
under placement of fill can range from 0.8 feet to 10.8 feet depending on the thickness of fill placement (5 to
1 0
feet) and YBM thickness (10 feet to
80 feet).
The settlement is projected to take place over
10 months
to 600 years depending
on the thickness of YBM.
The consolidation settlement
timing
can
be reduced
by
implementing
a
surcharge program with wick drains. If
a
surcharge program alone is not
feasible to mitigate the
anticipated
settlement, the existing fill can be removed and replaced with lightweight
materials.
Although shoreline a
reas along San Pablo Bay and the Mare Island Strait
have moderate to very
high liquefaction susceptibility
,
site
-
specific analysis by ENGEO (in letter to
Lennar Mare
Island,
LLC in January 2016
) concluded that the risk of liquefaction in planned development areas is generally
low
. However, lateral spreading remains a potential hazard in susceptible zones.
An overview of the existing sea
walls and discussion of the options and limitations associated with improving existing sea
walls to meet future sea level rise
was presented
.
The sea
wall was originally built by the Navy
and has been rehabilitated or repaired several
times since its
original construction (the oldest repair as
-
built drawings date back to 1922).
The existing sea
walls, if retained, would need to be raised by between 3.5 to
5.5 f
ee
t
to
meet
year 2070
SLR
projections
, and between 7
to
9 f
ee
t for
Year 2100 projections
.
There are two scenarios for protection from sea level rise. One is to raise the ground level to provide a nominal level of safety at the expense of initiating long -
term consolidation settlement.
Second is to install a barrier sea
wall, which would need to be supported by a pumping system to pump stormwater and seepage flows from behind the land side of the barrier.
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Two conceptual approaches to retrofitting the wall are presented. It is
acknowledged that
additional condition,
geotechnical
,
and hydrogeological investigations
will need to be
performed to determine design requirements of
retrofit solution
.
As a result of the initial findings of this study, an above -
water reconnaissance
-
level field assessment of
the Mare Island sea
wall
(bulkhead)
was conducted in April 2025 to document visible signs of deterioration, screen for structural concerns, and inform future inspection planning. The assessment included a visual, non
-
destructive inspection of the bulkhead wall and associated waterfront struc tures from both land and
water, spanning Berths 1 through 24 and grouped into 11 structural zones (Zones A through K).
Condition ratings for the seawall elements, based on ASCE Manual of Practice 130 ,
ranged
from Satisfactory (2
to 3
zones), to Fair (4 zones), to Poor (3 zones), with observed defects including broken sheet piles, severe cracking, spalling, delamination, missing tie rods, and sinkholes behind the wall near Dry Dock 2.
Two sinkholes
were
observed behind the bulkhead wall near Dry dock 2 and Building 340.
A
probable cause assessment and recommended repair approach are presented.
The
Bulkhead Wall Reconnaissance Level Condition Assessment Report is included
as
Appendix 6
B
.
Geotechnical Evaluation Recommendations
Because many
of the
development areas lack site
-
specific data, future project designs should not rely
solely on regional or historical data without confirming subsurface conditions through targeted investigations.
The type of subsurface
investigations and quantity of investigation will depend on the design requirements
and may
include:
Borings to characterize ground and groundwater conditions and to collect soil and rock samples for laboratory testing.
Laboratory testing to obtain design parameters for soil and rock underlying the project areas.
Soil testing to characterize ground conditions (e.g., depth to groundwater, liquefiable soil, lateral spreading potential, average shear wave velocity).
Seismic refraction survey to evaluate soil/rock interface profile on the southern side of the island for proposed improvements and new sea
walls.
In
-
situ permeability testing to assess
implications of water seepage through/under the
sea
wall
resulting from an imbalance of water pressures between
the
water side
and land
side
of the sea
wall
to
inform
designs to intercept and convey seepage water that could otherwise cause elevated
groundwater
levels within the interior of the island.
All infrastructure improvements should consider
site
-
specific geotechnical data and the
applicable building codes in effect at the time of design.
Regarding the sea
wall, two distinct sets of
recommendations are provided: one to address the physical condition and structural integrity of the existing wall, and another to support long -
term planning for
SLR
adaptation.
Condition and
Capacity of
Existing Sea
w
all Structure
(
building
on the 2025 sea
wall
assessment)
to support evaluation of
retrofit feasibility and future design
:
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Establish base vertical
load ratings for each sea
wall segment
to assess both original and
deteriorated capacity
.
Where original design documents are
unavailable, s
tructural
exploration including m
ap
ping
and
assessment of
deteriorated components
using
potholing and
ground penetrating radar (
GPR
)
scanning
will be required.
—
Conduct surveys:
▪
Topographic survey of existing sea
walls and waterfront structures to establish accurate
horizontal and vertical positions of seawalls, wharves, and dry dock structures.
▪
Aerial LiDAR survey to
determine areas of subsidence landside of the bulkhead.
These areas of subsidence are indicative of structural failure of the below -
grade
relieving platform or bulkhead walls.
▪
B
athymetric su
rvey
to determine seabed elevations and underwater conditions in front of the seawalls, supporting assessments of dredging needs for vessel access, evaluating slope and wall stability, and informing retrofit design. Surveys should also identify water depths at
active berths.
—
Structural exploration and
surveys should be performed prior to any other detailed inspection effort as they will help more efficiently guide inspection resources.
—
Perform Level I
–
III inspections of timber, concrete, and steel structural elements in
accordance with ASCE MOP 130, including underwater dive inspections and material sampling
. These inspections will
assess the extent of deterioration and guide the current structure load rating as well as potential structural repairs.
—
Investigate and remediate documented sinkholes
.
R
ecommended repair approaches are
provided in the
2025
report
.
—
Because many of the recommended assessments and
inspections are extensive and
time
-
consuming, they should be incorporated into a comprehensive sea wall
management strategy
.
This strategy should manage cost, schedule, and resources, and be integrated with Mare Island’s long
-
term shoreline planning and broader SLR
adaptation efforts.
Sea Level Rise Adaptation Planning Recommendations
support long
-
term shoreline
protection, adapt to projected SLR, and evaluate retrofit feasibility :
—
Conduct h
ydrological,
g
eotechnical
,
and
h
ydrogeological
i
nvestigations
to assess
subsurface conditions, seismic
risks
, slope stability, settlement potential, and seepage.
—
Assess future groundwater rise and its interaction with shoreline infrastructure .
—
Develop a
long
-
term shoreline strategy including a
future facilities plan for wharfage
integrated with coordinated land use planning.
—
Consider
state
-
of
-
the
-
art SLR adaptation strategies, including collaboration with property owners, developers, and specialist marine engineers, as well as alignment with national and global best practices for resilient waterfront redevelopment.
ROADS SYSTEM (CHAPTER 7)
The Mare Island road
s
system consists of approximately 28.3 centerline
-
miles of streets (86 street
segments
), with surfaces ranging from asphalt concrete (AC)
to unpaved gravel (mostly in the south end
of the island)
.
Road conditions are measured using the Pavement Condition Index (PCI), which scores streets on a scale from 0 (failed) to 100 (newly paved). At the start of this project, the City’s StreetSaver
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database covered 21.1 centerline
-
miles with an average PCI of 76.
During the project, a
n additional
5.4 centerline
-
miles of streets were added to the StreetSaver database in the south end of the island, which
have an average PCI of 49 (
not including
gravel roads).
For comparison, the overall PCI for the City of
Vallejo’s street network, updated in 2022, is 48.
The roads system evaluations were performed to understand the current condition and develop a proposed treatment
plan.
Evaluations included:
vehicle and walking pavement condition survey to verify the StreetSaver database and pavement condition; automated survey vehicle capture of imagery of the entire street network; field testing on critical streets and road materials to evaluate various para meters
(strength, thickness, layer composition, etc.); and developing appropriate pavement preservation, rehabilitation, or reconstruction treatments for arterial and major collector streets based on field testing, analysis, and applicable standards.
The field testing included falling weight
deflectometer
(FWD) testing, ground penetrating radar (GPR)
testing, dynamic cone penetrometer (DCP) testing, coring/boring, and laboratory testing of collected subgrade soil samples.
FWD testing was performed on 25.3 lane
-
miles of streets. The
average FWD deflection was
16.0 mils
(1 mil = 1/1000 of an inch)
, indicating medium structural capacity.
GPR testing was conducted on 40.0 lane
-
miles of streets.
The
streets average AC layer
thickness was estimated 5.
4 ± 2.5 inches.
A total of 60 cores and 3 bores were sampled and 43 DCP tests were conducted to estimate the existing pavement structural layer
thicknesses and other properties.
Coring data showed
that AC layer thicknesses ranged between approximately 1.3 and 16.1
inches, with an
average thickness of 6.9 ± 3.2 inches. The AC layers were thicker on major streets (average
7.3 ± 3.0 inches) than on residential streets (average 5.7 ± 3.5 inches). At several locations Portland cement concrete (PCC) or large aggregate siz
e macadam bituminous base layers
were identified under the AC layer.
The California Department of Transportation (Caltrans) Highway Design Manual (2022), the City roadway design standard, and engineering judgement was used
to
evaluate the pavement
structure and
identify
appropriate pavement
preservation,
rehabilitation
, or reconstruction
treatments
.
Roads System Recommendations
The following treatment
s
were
recommended for the selected design sections based on existing pavement condition and estimated traffic volume:
Do Nothing (12
design
sections
)
:
Sections recommended for no treatment are recently
paved or in very good condition; preservation may be
required in 5+ years
Slurry Seal (17
design
sections plus half of one
design
section)
Rubberized Cape Seal (7
design
sections plus half of one
design
section)
Cold
-
in Place Recycling (CIR)
with
hot mix asphalt (HMA)
overlay
(7
design
sections)
Mill
-
and
-
overlay HMA with base repairs (12 design sections
plus half of one
design
section)
Remove
existing asphalt concrete/aggregate base (AC/AB) and replace with HMA overlay ( 4 design
sections
plus half of one
design
section)
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The proposed treatments are based on the existing section conditions (late 2023). It is recommended the treatments are completed according to the following guidelines:
Complete the surface seal treatment repairs in the next 2 to 3 years
Complete all other rehabilitation treatment repairs in the next 3 to 5 years
Some roads, such as those in the Connolly Street Corridor, should be rehabilitated in coordination
with redevelopment and utility improvements
The recommended timing is to optimize treatment costs and slow the pavement deterioration to avoid
further higher cost
repairs.
That said, a multi
-
year pavement treatment plan always is subject to change should it be related to planned utility work that needs to be completed ahead of paving, unexpected scheduling delays, funding shortfalls, and planned development/construction. The
final treatment and
construction schedule needs to be re
-
evaluated and verified by the City based on existing pavement condition, construction budget, nearby development plan and anticipated uses.
DRY UTILITY SYSTEMS (CHAPTER 8)
Existing dry utility providers on Mare Island include:
Island Energy (electric and natural gas)
Comcast/Xfinity (cable communications)
AT&T (telephone and cable communications)
VIPFiber (City
-
owned broadband infrastructure)
The dry utility system evaluations included i
dentifying and contacting the existing dry utility providers on
the island; ob
taining and compiling existing mapping, plans, schematics, and reports which detail the extents
of the dry utility systems
; and d
iscussing with each of the dry utility providers their current coverage, planned expansions, and
concerns for
future
development.
Technical evaluations, mapping/field verification, or engineering of dry utility system capacity or condition was not performed.
A log of information received during this investigation is provided in Appendix 8A through 8D, organized by
utility company. No field verification of the information received was performed.
Facility sizes
.
C
apacities,
and locations
presented in this
report
should not be relied upon without
verification.
Dry Utility Systems Conclusions
The island’s dry utilities face similar issues to the wet utilities, but on a smaller scale. Many dry utilities have been installed or reconstructed after the Navy left, so the systems are generally newer
than the
water and sewer systems.
Dry utility infrastructure south of G Street is both functional and easily expandable to meet the needs of
new development.
Dry utility systems on North Mare Island are either non -
existent or rudimentary and
will need to be completely designed and constructed to
serve development
on the north
island.
In general, the dry utilities will have to accommodate sea level rise, although several of the dry utilities are not adversely impacted by wet or submerged conditions.
Although electric and natural gas
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infrastructure may be vulnerable to water intrusion, communication systems (e.g., VIPFiber, AT&T) are generally resilient to submerged conditions, with vault waterproofing required for maintenance access rather than operational integrity.
Additionally, since the dry utilities typically utilize smaller transmission systems, relocating these are less intrusive and disruptive than water or sewer upgrades or relocations.
Similar to the wet utilities, the dry utility companies are aware that any subsurface work on the island must be prepared to deal with the unexpected
,
such as abandoned
-
in
-
place buried infrastructure or
contaminated soil layers encountered during excavation.
The City and Mare Island Company should continue to communicate with dry utility companies to provide updates on future development and dry utility needs.
INTEGRATED RECOMMENDATIONS (CHAPTER 9)
Chapter 9 presents
both general conside
rations and
an integrated set of
infrastructure
improvements
covering
the
water, wastewater, storm drainage, roadway, geotechnical, and dry utility systems
across
Mare
Island
.
General considerations emphasize coordinated corridor planning, development flexibility, and climate resilience, with a focus on
construction, adapting to evolving land use and regulatory conditions, and proactively addressing sea
-
level
-
rise and
other natural
h
azard
risks.
An interactive WebMap (
https://arcg.is/0jyaei3
) displays recommended improvements by utility system
and land
-
use scenario, allowing users to explore recommendations in a geospatial context. Table 9 -
1 summarizes both system
-
specific and systemwide improvements
.
T
he
findings and recommendations in
this report form the foundation
for development of
a
coordinated, resilient, and cost
-
effective strategy
to support the long
-
term redevelopment of Mare Island.