A. INTRODUCTION

About San Geronimo Valley

San Geronimo Valley, located in the heart of Marin County, lies on both sides of Sir Francis Drake Boulevard and extends from the town of Fairfax to West Marin. The Valley is part of Marin County’s “Inland Rural Corridor” and, as the name suggests, it has a predominantly rural character. The Valley is a special place by virtue of the rich natural resources it enjoys. The redwood-, fir- and oak-studded hillsides of the area offer scenic views and protect the watershed’s health. A key functional and aesthetic feature of the Valley is San Geronimo Creek, which is part of the larger Lagunitas Creek Watershed. It is one of the last places along the central California coast to support a Coho Salmon population and one of the few places where people and salmon exist so closely together. In addition, the Valley enjoys significant conservation areas such as Roy’s Redwoods Preserve, French Ranch Preserve, Maurice Thorner Memorial Preserve, and Gary Giacomini Preserve.

Social History Of The Valley

The first people to discover the beauty and bounty of the San Geronimo Valley were Marin County’s original inhabitants, the Coast Miwok. From archeological evidence, we know they established seasonal camps thousands of years ago along what is now San Geronimo Creek, taking advantage of its robust runs of salmon, as well as the elk and deer herds that populated the hillsides, and the rich acorn harvest provided by the Valley’s many tanoaks and coast live oaks, which they tended assiduously. Sah-ta-ko means “People of the Tanoak” in Coast Miwok and is a name the inhabitants of this area gave themselves.

There is no word for “war” in the Coast Miwok language, and the people suffered tremendously following the settlement of San Francisco’s Mission Dolores in 1776. In 1770, there were between 1,500-2000 Coast Miwok living in their traditional territory of Marin and southern Sonoma; by 1880, only 60 remained. The last historic band of Coast Miwok - the Huimen Band – disappeared from the County by 1805. Their knowledge and stewardship of the land were replaced in the 1830s by Euro-American settlers who moved into the Valley to extract the abundant natural resources that had sustained the Coast Miwok for millennia. Valley industries throughout the 19th century included ranching, timber and logging camps, paper mills, powder mills, and fur trapping. Samuel P. Taylor’s mill, and other paper mills, dotted Lagunitas Creek downstream of the Valley.

The first instance of land ownership in the form of title-holding occurred in the Valley in 1844, when the Mexican government granted 8,800 acres called Rancho Cañada de San Geronimo (Valley of St. Jerome) to Rafael Cacho, a military officer and friend of General Mariano Vallejo. Rafael lived on the rancho with his family, grazing cattle and horses, for two decades. In 1864, he sold the property to Lieutenant Joseph Warren Revere, grandson of Paul Revere and American naval officer who had also served in the Mexican army under General Vallejo.

Early Coast Miwok lived in small hunter gatherer bands, with a diet that included salmon, acorns, nuts and deer. Original stewards of the land, the Coast Miwok managed its ecology and natural resources, and likely used controlled burning to increase forage for game, stimulate seed production, and regenerate the soil. For example, they managed vegetation cover using fire to encourage oak trees to grow and to create open space for deer and other desirable plants and animals (Joe Sanchez, documented MLD (most likely descendent) Coast Miwok by the Bureau of Indian Affairs, and member of the Coast Miwok Tribal Council of Marin County). The last historic band of Coast Miwok - the Huimen Band –disappeared from the County by 1805.

The Cañada [hollow or vale] of San Geronimo is one of the loveliest valleys in California, shut in by lofty hills, the sides of which are covered with redwood forests, and pines of several kinds, and interspersed with many flowering trees and shrubs peculiar to the Country. Through it flows a copious stream, fed by the mountain brooks; and the soil in the bottomlands is so prolific, that a hundred bushels of wheat to the acre can be raised with the rudest cultivation and other crops in corresponding abundance.

Title to the Rancho Cañada de San Geronimo property changed hands once again in 1868, when Adolph Mailliard - purportedly the grandson of Joseph Bonaparte, King of Spain and Naples, and brother of Napoleon Bonaparte – purchased the land for $50,000. Adolph constructed an 18room family home near Castle Rock in Woodacre, and in 1877, transferred title to approximately 450 acres (including present-day Roy’s Redwoods) to James and Thomas Roy in San Geronimo, who planted large fields of wheat in the rich meadowlands once stewarded by the Coast Miwok.

In the early 1900s, Adolph Mailliard’s heirs began subdividing the Rancho Cañada de San Geronimo property, and ultimately sold their remaining interest to the Lagunitas Development Company in 1912. The land was further subdivided to create the communities of Forest Knolls, San Geronimo, and Woodacre. In the early part of the century, homes in the Valley were used primarily as summer cabins, and the population never exceeded 4,000. The opening of the Golden Gate Bridge in 1937, and post-World War II growth, however, brought the potential for dramatic development.

In April 1961, the Marin County Board of Supervisors adopted a Master Plan proposal for the Valley that envisioned 20,000 new residents and substantial development. The Master Plan included amenities that would support – and be supported by – this influx, including 5,000 new multi-family residences, a Civic Center, shopping center, golf course, and a freeway crossing through present-day Roy’s Redwoods into Nicasio Valley. The 18-hole San Geronimo Golf Course was constructed on what is now the San Geronimo Commons in 1965, and a subdivision of 18 homes was built adjacent to the course. No other elements of the 1961 Master Plan were developed, and in 1973 – following extensive community involvement and advocacy - the Master Plan was rescinded and replaced by a Countywide Plan that incorporated environmental protection measures and significantly reduced the potential for development in the Valley.

Today the population of the San Geronimo Valley (including Woodacre, San Geronimo, Forest Knolls, and Lagunitas) is about 3,200. Throughout its history, despite many changes in land use, industry, and demography, the Valley’s rural character has remained and is widely cherished by today’s local communities.

San Geronimo Commons

The 157-acre San Geronimo Commons property -also referred to as Sah-tako Commons to acknowledge Marin County’s original inhabitants, the Coast Miwok -is situated in the heart of the San Geronimo Valley and framed by rolling hillsides – a location that provides both functional and aesthetic benefits.

The San Geronimo Commons stretches across the valley and is bisected east to west by Sir Francis Drake Boulevard, an important twolane arterial road that connects San Rafael to State Route 1 and serves as the gateway to West Marin. Nicasio Valley Road, San Geronimo Valley Drive, and Lagunitas School Road also border the property. Point Reyes Station is approximately twelve miles to the northwest of the property. San Rafael is eight miles to the southeast, and about eighteen miles further south is the city of San Francisco.

The property serves as a geographic hub and critical wildlife corridor linking over 100,000 acres of largely contiguous public open space from the Golden Gate National Recreation Area to the Point Reyes National Seashore. It is surrounded by Marin County open space preserves as well as large swaths of state and national park lands. Single-family residential homes dot the landscape immediately adjacent to the property and surrounding open space areas. Miles of regional hiking and biking trails begin at the property’s boundary, and an existing network of older paved paths on the property currently accommodate walking, jogging, bicycling, safe routes to school, nature viewing, and quiet contemplation.

A small pedestrian tunnel under Sir Francis Drake Boulevard, several bridges, a 15,000-square-foot clubhouse building, and a 200-car parking lot are also present on the property, and support access and circulation for passive recreational opportunities such as hiking, bicycling, and horseback riding.

The San Geronimo Commons property includes three large parcels –

• The Larsen Meadow parcel north of Sir Francis Drake Blvd and west of Nicasio Valley Road,

• The Clubhouse parcel northeast of the intersection of Sir Francis Drake Boulevard and Nicasio Valley Road, and

• The San Geronimo Meadow parcel bordered by San Geronimo Valley Drive south of Sir Francis Drake Blvd

Lagunitas Creek Watershed

The San Geronimo Commons is situated along San Geronimo and Larsen Creeks in the upper reaches of the Lagunitas Creek watershed, a precious natural asset in the heart of rural west Marin County. Draining the largest watershed in Marin County, Lagunitas Creek flows approximately 22 miles from its headwaters on Mount Tamalpais to its mouth at the southern end of Tomales Bay. San Geronimo Creek is the last undammed tributary of Lagunitas Creek, and while it accounts for less than one tenth of the total watershed, its lack of dams and relatively natural hydrograph have consistently sustained almost half of the recorded Coho Salmon spawning sites in the watershed. However, while it remains a crucial resource, the main stem of San Geronimo Creek has been degraded over time by excessive runoff, channel incision and erosion, and is now much more confined and disconnected from its floodplain and riparian corridor compared to historic conditions, as discussed below. San Geronimo Creek supports a mature but narrow riparian corridor characterized by a mix of Coast Live Oak, Valley Oak, Alder, Willow and Cottonwood trees. Sections of riffle pool channel and gravel bed channel are maintained by shallow bedrock as well as woody debris accumulations.

Larsen Creek, a smaller, ephemeral tributary to San Geronimo Creek, also provides habitat for different life stages of salmon and steelhead populations, and makes important contributions to riparian ecosystem functions to the watershed. Two named forks of Larsen Creek flow through the Commons: the main channel and the North Fork of Larsen Creek.

Before entering the San Geronimo property, the main channel of Larsen Creek flows through Roy’s Redwoods

Preserve where it has been impacted by informal trails and compaction of the forest floor in the park’s old-growth redwood grove. Larson Creek’s main stem is characterized by two distinct reaches, upstream and downstream of a large bedrock outcrop in the channel that forms a natural barrier to upstream migration by salmon and steelhead. The downstream reach, the majority of which flows through the San Geronimo property, is a small, highly confined gravel bed channel experiencing similar erosional processes and floodplain disconnection as San Geronimo Creek. The creek currently enters the property under Nicasio Valley Road at the property’s northeast corner, where approximately 1,500 feet of the creek has been buried underground in culverts and routed through two constructed ponds on the San Geronimo property. Similarly, several seasonal drainages to Larsen

Creek have been routed through culverts to support past land uses.

The North Fork (NF) of Larsen Creek is a small channel within a mature and relatively intact riparian corridor. NF Larsen Creek is formed by two headwater tributary streams that are characterized by steep, well defined channels that extend upslope on the surrounding hills, delivering stormwater flows to the creek in winter, and providing terrestrial wildlife habitat and cover year-round.

Ecological Setting

The Lagunitas Creek watershed, which includes San Geronimo Creek, has statewide significance as a home for protected aquatic species, including Coho Salmon, Steelhead Trout, and California freshwater shrimp. The Lagunitas Creek watershed supports the most viable wild population of endangered Central California Coast Coho Salmon, making up nearly 10% of the state’s Coho Salmon population. The watershed also supports one of the largest remaining populations of endangered California freshwater shrimp in the State, making it an important stronghold for the species.

Other special status species that occur in the Lagunitas Creek watershed include Northern spotted owl, California red-legged frog, foothill yellow-legged frog, and tidewater goby. Notable native species that occur in the watershed include river otter, Pacific giant salamander, the California and rough-skinned newts, and northwestern pond turtles (California Species of Special Concern). Because of this diverse community of sensitive species and critical habitats, the Lagunitas Creek watershed has long been viewed as an important priority location for conservation efforts and species recovery.

The San Geronimo Commons property historically supported a broad, complex riparian corridor, including connected floodplain areas set within native grasslands and surrounded by oak woodlands and redwood forests. These native grasslands, oak woodlands, and redwood forests were largely converted to rangeland, and subsequently, to a 19-hole golf course. Modifications to the property to accommodate these uses included removal of many small streams that once drained the adjacent hillslopes and flowed through the landscape as well as the creation of artificial topographic features. These changes degraded and fragmented the habitats, and compromise landscape connectivity and wildlife movement across the Valley and between existing open spaces. Although the property has been altered over timein ways that have impacted the type, quality, and extents of habitat areas – the property continues to provide important, albeit limited, breeding, overwintering and migratory habitat for a range of aquatic and wildlife species and, most importantly, now presents unique opportunities and a vital resource for species recovery and climate resilience.

Salmon and Steelhead in San Geronimo Commons

Coho Salmon and Steelhead Trout belong to the fish family commonly referred to salmonids. Salmonids have a very unique and sensitive lifecycle. The lifecycle begins with adult salmonids laying eggs in the gravel beds of creeks. Their juvenile offspring spend their early life in those creeks for a period of months to years until they grow large enough to migrate out to the ocean. Once in the ocean, they mature for several years, and eventually return to their natal creeks (where they were born) to lay their eggs as adults, restarting the entire cycle. Each stage of this complex lifecycle requires the right watershed conditions: the absence of barriers for fish migrating upstream; clean gravel and cold water for egg incubation; cool, deep, well-shaded pools to shelter juveniles during the summer; floodplains, off-channel alcoves and fallen trees to shelter juveniles from fast flowing winter floods; and a healthy riparian corridor to provide shade, cover, and an ongoing source of river wood and food. Despite making up only 10% of the total watershed, San Geronimo Creek supports 40% of the Lagunitas Creek Coho Salmon spawning, and over 30% of the watershed’s juvenile rearing habitat. The San Geronimo Commons property annually supports active spawning sites for Coho and steelhead, and observations of redds (or egg nests) documented by the Marin County Municipal Water District specifically show a high density found on the property extending from Roy’s

Pools upstream to the confluence with Woodacre Creek.

Salmonids enter the Lagunitas Creek watershed from Tomales Bay and make their way up to the San Geronimo Valley in the late fall and winter after storm events. Main stem San Geronimo Creek is one of the primary spawning areas for salmon and steelhead. Spawning also commonly occurs in lower Larsen Creek although juvenile fish move into San Geronimo Creek as seasonal flows recede. Juvenile Coho stay in the Lagunitas Creek watershed for approximately one year after emerging. Steelhead may remain for one to four years in their natal stream, while Chinook (limited observations and documentation) only remain for a few months. Depending on habitat conditions, some juvenile salmonids remain near where they hatched, while others migrate further upstream, or move downstream to Lagunitas

Creek in search of quality habitat conditions. San Geronimo Creek currently provides some of the most persistent summer rearing habitat for juvenile fish, as other tributaries in the Valley typically dry out. Salmon population numbers in San Geronimo Valley are highly variable in any given year, but long-term population trends make it clear that statewide Coho salmon populations, and the population in San Geronimo Valley, are in crisis. Preserving and restoring Coho and other species populations depends on creating self-sustaining watershed conditions to support their varying lifecycle needs. The Commons property has great potential to provide for those needs through an intentional program of preservation, enhancement, restoration and expansion of habitat conditions and ecosystem functions.

The Need and Opportunity for Restoration and Ecological Management

Though still one of the most favorable locations for salmonid spawning and rearing on the entire Central California Coast, San Geronimo Creek has been impacted by human development in the watershed. The creek once supported a broad riparian forest with a well-connected floodplain surrounded by grass and forested uplands. However, increased stormwater runoff due to historic logging, land clearance, culverting of tributary streams and drainages, and urban development has caused San Geronimo Creek to erode down into its bed over many decades, becoming entrenched and disconnected from its historic floodplain in the process. This has had several impacts on watershed health. Winter flows that would have spread out across alluvial fans (sediment accumulations) or spilled out onto the floodplain and created wetter habitat are now rapidly connected through ditches and culverts and concentrated in the channel. These changes dry the floodplains out, reduce groundwater infiltration, funnel more water more rapidly downstream, and degrade riparian habitat. The confined channel is faster-flowing and more erosion-prone than it was prior to development, scouring away the gravels in which salmon and steelhead lay their eggs, as well as eroding the creek banks causing a loss of trees and valuable shade. The flashier and more intense flows flush out juvenile salmonids and/or force them to expend valuable energy fighting stronger currents. These conditions are present in San Geronimo Creek throughout the property, threatening current and future habitat quality for salmonids and other aquatic species and limiting the extent and health of adjacent riparian habitat.

However, the San Geronimo Commons property offers unique and important restoration opportunities along significant lengths of these two streams – San Geronimo Creek and Larsen Creek - with the potential to create more complex and expansive riparian floodplain habitat that provides high-quality spawning, rearing, and refuge habitat for fish; valuable breeding and stopover habitat for birds; and improved winter groundwater recharge, summer streamflow, and water quality throughout the year. These opportunities will build off recent and planned actions to remove fish migration barriers (Roy’s Pools and San Geronimo Valley Drive) and expand floodplains, and they include the potential to restore additional reaches for salmonid spawning and rearing. The restoration of connected and complex floodplains on Larsen Creek and San Geronimo Creek will create broad and sustainable riparian corridors around the creeks that support many species of fish, birds, and animals, and function as wildlife corridors between adjacent open spaces. On Larsen Creek there are opportunities to restore headwater hydrologic processes that improve groundwater recharge and reduce fine sediment, as well as to daylight and restore the culverted portions of the creek and its tributaries within the San Geronimo Commons. These efforts could contribute importantly to habitat and water quality improvements on both the property and downstream reaches of San Geronimo Creek.

There are also opportunities to manage and/or enhance the constructed ponds located on the San Geronimo Commons. Several ponds provide aquatic and wetland habitat for a diversity of wildlife, as well as scenic and recreational values, but they currently harbor predators such as largemouth bass and American bullfrog that prey on native fish and frogs.

Former fish Ladder at San Geronimo Creek prior to restoration aided adult salmon, but created poor habitat conditions for young coho salmon and steelhead trout and limited juvenile fish migration downstream.

Land Use and Planning Context

A majority of the land within the ~6,000-acre San Geronimo Valley is privately owned, with singlefamily residential uses representing approximately 30% of total land ownership, followed by agricultural ownership at nearly 10% and institutional ownership (including the San Geronimo Commons) reflecting another 10%. The Marin County Open Space District is the largest public landowner, owning and managing about 37% of the watershed as public open space lands, reflecting local commitment to preserving the rural character of the area.

The San Geronimo property is under the jurisdiction of Marin County and is zoned Resort and Commercial Recreation District (RCR). The Marin Countywide Plan land use designation is Recreational Commercial (RC).

The current use of the property as open space complies with County zoning ordinances and plans, and is consistent with the San Geronimo Valley Community Plan, adopted as part of the Marin Countywide Plan.

The Resort and Commercial Recreation zoning district is intended to create and protect resort facilities in pleasing and harmonious surroundings, with emphasis on public access to recreational areas within and adjacent to developed areas. Permitted uses in the RCR zone include visitor-serving commercial uses, such as lodges, bars, and restaurants. Conditional uses allowed with a permit include community centers, outdoor commercial recreation, and playgrounds.

In addition to the Marin Countywide Plan, the Marin County Zoning Code and the San Geronimo Valley Community Plan apply to the San Geronimo Valley community. The San Geronimo Valley Community Plan, which was adopted as part of the Marin Countywide Plan, presents goals, objectives, policies, and programs that aredesigned to preserve the unique natural attributes of the Valley and its communities as well as the historical character of the built environment. The Plan provides direction to property owners, community groups, and interested individuals in formulating and reviewing new developments.

This Vision Framework is not a Master Plan or set of design proposals. Rather, it is a guide for future land owners and managers that sets forth conservation priorities for the property and outlines conservation-and wildlife-compatible recreational and community land use opportunities.

Implementation and activation of many future uses discussed in the Vision Framework may be subject to local and Marin County planning requirements, environmental review, public review and comment, and/or due diligence activities such as soils testing and engineering assessments.