King Tides

Several extremely high tides at the turn of the year flooded the marsh at Hal Brown Park at Creekside, giving a preview of future sea levels. Photo by Sandy Guldman

The California King Tides Initiative encourages members of the public to document the highest seasonal tides (or king tides) that occur along the state’s coast. These photographs help us visualize the impact of rising waters on private property, public infrastructure, and wildlife habitat across the state. Visit www.californiakingtides.org

Friends Volunteers Refurbish Kiosk at Remillard Park

Nick Salcedo and Sandy Guldman show off the illustration of pond life. Photo by Laura Lovett

The small park and pond next to the bay on East Sir Francis Drake Boulevard, known as Remillard Park, has beautiful new interpretive signs thanks to Laura Lovett and a small posse of volunteers. Laura colorized a drawing of pond life originally created for Marin Audubon by Jennifer Dewey, for one side of the kiosk, and designed an illustration of the hazards of litter on the other. The Marin County Fish and Wildlife Commission provided funding for expenses, Booth and Little Roofing and the City of Larkspur made in-kind contributions. Stop in and enjoy the park and signs!

Tree Removal at Habitat Restoration Site

Friends’ native woodland restoration site on College of Marin land adjacent to the multi-use which follows Corte Madera Creek, can breathe more freely with the removal of two large eucalyptus trees in early October. When a grove of acacias was removed in 2005, these two trees were left as a screen for users of the path, and we planted young oaks, box-elders and shrubs beneath them. However chemicals running off the eucalyptus leaves retarded the growth of the natives, and large limbs were frequently falling, endangering people and plants.
Thanks to the skill of Fahy Tree Service workers, very little damage was done to our plantings, and we were left with a large pile of mulch to use.
A grant from the California Alpine Club Foundation enabled us to carry out the work, together with funding from COM.

The Ecology Study Area, Kentfield. Photo by Charles Kennard

Workers use a winch to lower branches to the ground, avoiding damage to young plants. Photo by CharlesKennard

Less Garbage on the Shore

A surprise downpour on Coastal Cleanup Day failed to stop volunteers from their work of picking up trash along the Corte Madera Creek estuary on September 21. Fifty-two participants—including the San Domenico students pictured—collected 165lbs. of litter, including 25lbs. of recyclables. This was considerably less than the half-ton or more collected in previous years, and according to Nick Salcedo, one of the organizers for Friends, this may have been because people didn’t take on the challenge of heavy items stuck in the marsh. Photo by Sandy Guldman.

Culvert Replacement and Tidal Marsh Creation at Hal Brown Park

by Sandy Guldman

The culvert at Hal Brown Park, where it connects with Corte Madera Creek. Photo by Sandy Guldman

The southeastern section of the marsh at Hal Brown Park suffers from limited tidal action and, in some locations, very poor soil. With funding from the Regional Water Quality Control Board’s program to direct fines to a Special Environmental Project (SEP), we have designed a project to replace the single 60-inch culvert just upstream of the Bon Air Bridge with a 5-foot by 12-foot box culvert. This culvert will allow more tidal flow into the marsh and increase the tidal prism in Corte Madera Creek, a component of the sediment management program in the Ross Valley Watershed Program.
In addition to enlarging the culvert, we will create new marsh habitat by exchanging hard, gravelly soil that has no vegetation with bay mud excavated from under the culvert location. The soil that is unsuitable for growing marsh plants will be used to support the new culvert and the bay mud will allow marsh vegetation to flourish. The SEP provided enough funds to replace the culvert if large amounts of soupy bay mud did not need to be excavated and replaced. However, we do need more money, so we are seeking additional funds for the marsh creation.
As the owner of Hal Brown Park, Marin County Parks is a major partner in this project. They are the lead agency for environmental review and will put the contract for the construction out to bid.


Lansdale Fish Passage Project

The Lansdale Fish Passage Project, completed in early October 2012, performed as designed, both during the big storms of December 2012 and at lower flows suitable for fish passage. Only missing were spawning steelhead trout. No sediment has blocked fish passage, although a few gravel bars have developed in the edges of pools. Some sediment in the fishway and baffles is beneficial. It provides camouflage for fish, a more natural bottom that may harbor macro-invertebrates, and roughness that can damp oscillations.
Our main task now is watering and weeding the plants installed last winter. While we are waiting for a water connection to be installed by MMWD, the Town is using a water tank in the back of a pick-up to deliver water to the drip irrigation system. It will certainly be easier when there is a permanent hook-up and a timer to operate the system.

Project News

July 2013

Flood Management and the Ross Valley Watershed Program
Phoenix Lake Retrofit:

The Department of Water Resources has awarded $7.66 million to the Marin County Flood Control District’s Ross Valley Watershed Flood Protection Program for the Phoenix Lake Retrofit Project. The total project cost is $15.6 million. The heart of the project is retrofitting and seismically up-grading the dam at Phoenix Lake, allowing the lake to be operated for flood management, drinking water supply, water quality improvements in Phoenix Lake and Ross Creek, ecosystem restoration, and public recreation improvements. The project will be developed in partnership with Marin Municipal Water District.

Memorial Park Detention Basin
The Department of Water Resources has made a tentative award of $8.72 million to the Town of San Anselmo for the Memorial Park Detention Basin. The total project cost is $17.4 million. The project includes lowering the elevation of the playing fields, improving drainage, refurbishing the park, and day-lighting Sorich Creek. The detention basin would be used when flooding is imminent in downtown San Anselmo; it would hold about 8-10% of the out-of-bank flow in San Anselmo. The project will be developed in partnership with Marin County Flood Control District.

Lefty Gomez and Loma Alta Detention Basins
The Marin County Flood Control District is negotiating with the Ross Valley School District and Marin County Parks for permission to begin preliminary studies at these two potential detention basin sites.

FEMA Flood Insurance Rate Maps (FIRMs)
FEMA has released revised FIRMs for the Ross Valley. Visit the FEMA Map Service Center web site to find the map of your neighborhood. Check with the jurisdiction where you live for more details.

Corte Madera Creek Flood Control Project
Marin County and the US Army Corps of Engineers are working on a new funding agreement so that work can proceed on the project. The earlier funding agreement (98.5% federal, 1.5% local) dated from the 1960s. The insistence by local groups to maintain that very favorable cost-share had the effect of squelching all funding. There is some optimism that with a new agreement that meets current requirements work will move forward on completing the work on Units 3 and 4 in Kentfield and Ross. Removing that constriction at the bottom of the riverine reach of the watershed is crucial to moving forward with the Ross Valley Watershed Program.

Friends’ Active Contracts
1.    Invasive Spartina Project, funded by the California Coastal Conservancy
$109,937 provided by the Coastal Conservancy for the 2011-13 treatment season.
Scope: Friends is the local sponsor of the Coastal Conservancy’s Invasive Spartina Project, an effort to eradicate invasive cordgrasses throughout the Bay. Our participation began in 2002; we expect several more years of work before the project can be declared a success. Even then, we will continue monitoring to find and remove plants that persist in some locations.

2.    Replacement of Culvert at Hal Brown Park at Creekside to increase the tidal prism and enhance habitat. The 50% designs have been prepared and environmental review is in progress.
$249,370 provided by the Regional Water Quality Control Board with fines assessed to the Ross Valley Sanitary District
$200,000 in additional funds being sought from other sources
Scope: Design project, obtain permits, replace culvert, enhance tidal marsh, and monitor for five years

Mulching coyote brush plants. Photo by Kirk Schroeder

3.    Planting at Hal Brown Park at Creekside to enhance habitat, funded by the City of Larkspur to compensate for the unavoidable impacts to tidal marsh during the planned replacement of the Bon Air Bridge
$52,000 provided by City of Larkspur
Scope: Plant 0.529 acres of tidal marsh and upland refugia and monitor for five years

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