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Bulletin Board
High Selenium in the Bay
New research by the U.S. Geological Survey found levels of the naturally occurring trace element selenium - associated with the front-page waterfowl deformities at Kesterson willdife refuge in the 1980s - are not only higher in Suisun Bay than previously thought, but also could be strongly influenced by river inflows. According to a paper in the Regional Monitoring Program 1995 annual report, high inflows in May 1995, for example, coincided with the lowest concentrations of selenium in resident clams while subsiding flows in October 1995 increased selenium concentrations. Thus the amount of freshwater flow appears to influence the bioavailability of selenium to clams, and the sturgeon, birds and other life that feed on them. "Our findings could have implications for Delta water management and agreements," says the Survey's Sam Luoma. Also influencing selenium's creep up the food chain is the invasion of the Asian clam (Potomorcorbula amurensis), shown to concentrate 2-3 times as much selenium as other residents in 1984-86. Luoma and others are now working to answer a new spate of research questions including which types of selenium are producing the high readings in Suisun Bay and from what sources - the Asian clam, Central Valley drainage (see p. 5), or nearby oil refineries? Contact: (415)329-4481
Wetland Debits and Credits
Building seawalls, riprap shores and boat docks are just some of the small Bay fill projects that over decades have claimed acres of Bay wetlands. Many such projects are too small to justify eye-for-an-eye mitigation in terms of protection or restoration of equivalent wetland resources. However, the new S.F. Bay Wetland Mitigation System proposed by the staff of the S.F. Bay Commission might for the first time offer a process and currency for dealing with small wetland debits and credits, as well as a field test for revamping mitigation approaches for larger ones. The proposal, now in its fourth draft, received its first public hearing at BCDC on April 17 and could be implemented early as 1998. Contact: (415)557-8775
Ecosystem Re-Hab
CALFED, a cooperative federal and state effort to develop a long-term solution to Bay-Delta water conflicts, released a 68-page executive summary of its Ecosystem Restoration Plan at a public workshop early this April. The summary is short on prose and long on detailed action lists but basically embraces the following systemwide targets: restore 75,000-120,000 acres of freshwater and brackish tidal marsh, and shallow water habitat, as well as 100-200 miles of riparian woodland and shaded riverine areas; provide 300,000-500,000 acre feet of increased critical period flows to restore physical processes and ecological functions; replace 40-100 tons of river and streambed gravel annually to enhance anadromous fish spawning; provide new or improved fish passage aids and fish screens at selected diversions; develop floodways on the San Joaquin and Cosumnes Rivers; manage undesirable and interfering introduced species; and manage water quality problems that degrade ecosystem health. The full-fledged plan will debut this May. Contact: (916)657-2666
Stormdrain Retrofits
Technology can do its part to help clean stormwater racing down the drain with its pollutant payload of heavy metals, oil, grease and sediments. Several enterprising companies have, for example, developed filters to attach to drains. According to EPA's Nonpoint Source News Notes, the "Enviro-Drain" filters runoff through three trays - the first stalls sediment and debris; the second removes oil, and the third neutralizes fertilizers and pesticides (cost $400 to install and $3-10 to replace filters monthly). KriStar's "Fossil Filter" captures contaminants in a metal trough (installation $500-600, plus trough cleaning costs every six months). A more permanent solution is a "Stormceptor" - a precast concrete system fitted underground which traps petroleum and suspended solids. Although it costs a lot more than the filters to install ($7,600-$33,500), the once-yearly maintenance via vacumn trucks is easier on manpower and the pocketbook. (None of the costs above include disposal.) Contact: Enviro-Drain (206)820-8364; KriStar (800)579-8819; Stormceptor (800)762-4703.
Watershed Science Blueprint
"A holistic approach to watershed management" is how the Coyote Creek Riparian Station's Mike Rigney describes the S.F. Estuary Institute's new Bay Area Watersheds Science Plan, released in draft this January. The plan sets forth a three-phase program for developing comprehensive scientific information on local watersheds, and then using that information to set goals for watershed health and to monitor progress. The plan calls for extensive research and field reconnaissance, including developing a Geographic Information System map of the watershed, habitat surveys and data collection on topics such as soil types, vegetation, rainfall and stream flow. Because water quality is a top priority of watershed management, the plan emphasizes the need for detailed inventories of pollution sources and potential controls. The plan also calls for the participation of trained volunteers. Rigney says that although numerous state and federal programs acknowledge the importance of watershed health and management, until now there have been no guidelines on how to inventory, assess and monitor watershed functions. Contact: (510)231-9539
Channel Island Coordination
About 800 often-overlooked fragments cut off from larger Delta islands by dredging are the subject of a "Coordination of Efforts" currently being circulated by the S.F. Estuary Project. The non-binding document - drafted by the Project's Delta In-Channel Islands Workgroup - stipulates a commitment to protecting the islands, which are home to fish, wildlife, wetland and riparian plants, and numerous special status species. As a step toward coordination, the workgroup is now part of CALFED's Levee and Channel Technical Team. Project staff hope to get at least 50 signatures on the coordination document from interest groups, landowners and agencies. To see or sign, contact (510)286-0924
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