Chapter 3
Chapter 4
Chapter 5
Chapter 6
Chapter 8
Chapter 9
Chapter 10
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The phasing of wetlands restoration projects is one of the key issues that led to the Goals Project. At the heart of this issue is the need to provide for lost habitat functions when diked lands are restored to tidal marsh. In the past, this issue arose primarily when seasonally ponded areas of farmed baylands were restored to tidal marsh. In the future, it will occur in similar instances and also when salt ponds are restored to tidal marsh. To ensure no overall loss of habitat functions, tidal marsh restoration should be undertaken in a way that concomitantly develops or enhances the functions of the habitats it displaces. Whenever possible, managed seasonal ponds or managed saline ponds should be developed or enhanced before tidal restoration occurs in order to ensure adequate habitat diversity. Generally, this should take place in the same subregion as the tidal marsh restoration.
Contaminants such as lead, copper, mercury, petroleum, and pesticides may be found throughout the baylands ecosystem, and their concentrations vary greatly in water and in sediments. The design of wetlands restoration and enhancement projects must, therefore, include an evaluation of the potential problems that contaminants may pose to the ecosystem. The kinds of projects in which contaminants must receive especially careful consideration include the use of dredged material for restoring intertidal habitat and tidal marsh, the use of sewage sludge in diked wetlands, the use of wastewater to create or restore marshes, and the use of wastewater for streamflow augmentation. Contaminants are a major concern in the development of treatment marshes for municipal or non-point discharges. These marshes should be carefully designed, managed, and monitored to ensure that they do not pose a threat to biota. Some segments of the baylands are generally more contaminated than others, based on past or current land use. These include the highly industrialized parts of the Central Bay, especially the western shoreline between San Francisco and the San Mateo Bridge, and along the East Bay shoreline between Richmond and San Leandro. Wetlands restoration projects planned in these segments, especially at sites with a history of industrial activity or use as formal or informal landfills, should include careful assessments for contaminants. Adequately addressing potential contaminant problems will ensure that the restored baylands habitats provide for a healthy community of plants, fish, and wildlife.
Each year about six million cubic yards of sediment are dredged from the Bay. This material is disposed of in the ocean, at in-Bay sites, and at some upland sites, particularly land fills. In recent years, dredgers and the agencies that regulate the discharge of dredged material have been interested in expanding the beneficial uses of some of this material. There is much interest in placing dredged material in diked portions of the baylands in conjunction with wetlands restoration. Many areas of diked baylands have subsided substantially since they were isolated from tidal waters decades ago. Subsidence of diked farmed areas is caused by soil decomposition, wind erosion, and compaction of organic soils. Groundwater pumping has contributed to the subsidence of diked areas, especially in the South Bay. In subsided areas, restoring tidal marsh or creating shallow ponds for wildlife may require elevating the bottom substrate. The use of dredged material is a way to accelerate this process, especially where the suspended sediment supply is limited. Dredged material also may be used to restore a full range of marsh, beach ridge, roosting island, and other habitat that may not develop through natural processes. Project participants believe that tidal marsh restoration and the conversion of salt ponds to managed saline ponds should rely on natural processes to the maximum extent possible. This is particularly important when establishing the final substrate of a pond or the marsh plain. However, in certain locations, and in order to meet specific project design objectives, the use of dredged material may be an appropriate adjunct to natural sediment deposition. If a restoration project incorporates the use of dredged material, care must be taken to avoid potentially negative effects. These include the possibility of overfilling, inhibiting proper slough channel formation, and potential contaminant impacts on biota. The decision to use dredged material for wetlands restoration needs to be made on a project-specific basis. We recommend that dredged material be used very selectively, only when it is of suitable quality, and when its use will result in an essential ecological restoration benefit that cannot be achieved better through natural means.
Each day, municipal wastewater treatment plants discharge more than 600 million gallons of treated wastewater to the Bay. Most of this is discharged to deep water areas and does not significantly affect the baylands. However, discharges of treated wastewater to sloughs and shallow areas may cause problems such as the conversion of tidal salt marsh to brackish marsh. In the Bay Area, this conversion problem is most apparent in the South Bay, where discharges from the City of San Jose's treatment facility into Artesian Slough have caused large areas of nearby tidal marsh to become more brackish. This conversion has degraded the habitat of several salt marsh dependent species. To avoid the problem of marsh conversion experienced by San Jose, managers of the Hayward wastewater treatment plant mix the treated wastewater with Bay water in the Hayward Area Recreation District Marsh before discharging it to the Bay. Wastewater can also be used to provide valuable habitat. Most wastewater treatment facilities have ponds in which water is stored before being discharged, and some of these ponds are used by waterfowl and other water birds. Some treatment plants use marsh vegetation to remove, or polish, additional pollutants from wastewater before it is discharged to the Bay. An example of this kind of facility is at the Demonstration Urban Stormwater Treatment Marsh in Hayward, where ponds include vegetated and unvegetated areas and have constructed islands for nesting birds. This site provides high quality habitat for wintering waterfowl, nesting egrets and terns, and resident shorebirds. To ensure that the discharge of treated wastewater to marshes does not adversely affect biota or water quality, careful monitoring is necessary. Recycling treated wastewater is a beneficial alternative to direct Bay discharge, and recycled water can be used in several ways to improve habitats. One way is to use it in conjunction with salt ponds. For inactive ponds that are to be restored to tidal marsh, treated wastewater may be used to dilute brines and bittern before discharging them to the Bay. For ongoing salt production, it may be possible to use fresh water to dilute bittern enough to allow its discharge to the Bay; without the need for bittern storage, the existing bittern ponds could be restored to tidal marsh. Recycled wastewater also may be used as a water source to create new wetlands or to restore or enhance managed and diked marsh habitats on the periphery of the baylands, especially where historical seeps and small drainages no longer occur, to strengthen brackish marsh gradients. In some situations it may be beneficial to use it to augment streamflows in order to enhance instream habitat. In any case, the effects of discharging the recycled water should be carefully considered beforehand, flows should be free from potentially harmful pollutants, and the receiving wetland or stream should be carefully monitored for long-term effects.
A major issue associated with salt ponds is how to dispose of the concentrated liquid end products. This issue pertains to situations where salt is commercially harvested and to ponds that are managed as shallow saline habitat. In the case of active salt production, these liquids are known as bittern; they contain the magnesium-potassium salts that remain after sodium chloride has been harvested from Bay water. Currently, bittern is stored in holding ponds of several hundred acres. In managed saline ponds, the liquid would be a hypersaline brine that exceeds Bay salinity. We need to find a way of disposing of bittern and brines in order to facilitate salt pond management and restoration. The disposal of bittern and hypersaline brines from salt ponds is restricted by the basin plan requirements of the Regional Water Board. Bittern disposal is restricted because of its acute toxicity to aquatic organisms if discharged in a concentrated form; toxicity is a result of high biological oxygen demand. To overcome this toxicity, bittern must be diluted up to two hundred times. The discharge of hypersaline brine is prohibited because brines exceed background salinity requirements. Concerns also exist about the possibility of contaminants in these materials. The successful restoration of bittern ponds and brine ponds to tidal marsh will require disposing of bittern and brines. Criteria must be established to determine how, and under what circumstances, these liquids can be discharged back into the Bay. This determination is also needed to facilitate the operation of managed saline ponds. In the absence of salt production, these ponds will concentrate salt, and managers will need the ability to discharge the brines so that they can provide optimum habitat conditions for water birds.
In developing habitat recommendations, there has been strong agreement regarding the need to protect existing and restored wetlands from factors that diminish wildlife habitat quality. It makes little sense to expend private or public funds to restore a site, only to have its biological functions compromised by residential and industrial activities, dogs and cats, unrestricted entry, and illegal dumping. One of the best ways to help ensure that the baylands provide maximum benefits for wildlife is to incorporate buffers into project design and management. A buffer is a zone of transitional or upland vegetation that abuts a wetland or stream; it is regulated to control the negative effects of adjacent development from intruding into the natural area beyond. To be effective, buffers for wetlands should be as wide as possible, and the optimal width will depend on the baylands species to be protected. Project participants recommend a default buffer width for wetlands of 300 feet. Where existing land uses or other factors preclude this, buffers should be no narrower than 100 feet. Along streams, buffers should be at least 100 feet wide, measured from the outer edge of riparian vegetation on each side of the stream. The purpose of a buffer is to minimize disturbance to a particular habitat area. Accordingly, most buffers should be fenced to prevent entry of humans, dogs, and livestock. However, there may be some instances where buffers may not require fencing. Each case must be carefully studied to determine appropriate buffer design. Buffers should be considered an integral part of every wetlands restoration or enhancement project. Funds for their acquisition, design, and long-term maintenance should be provided along with other project funding.
In recent years, the public has become increasingly interested in gaining access to the Bay's shoreline for recreational enjoyment. The Bay Conservation and Development Commission has been instrumental in opening up the shoreline and, more recently, the Bay Trail Project has sought to improve hiking and cycling access. Likewise, many cities and counties are encouraging recreational uses of the baylands. Agencies that encourage access to the Bay are fulfilling a part of their public trust responsibility as they enable people to use a public resource. They also are helping to ensure long-term Bay protection as people who can use the Bay likely will seek to protect it. At the same time, however, there have been instances where some of the resource agencies considered the access inappropriate. Balancing public access and natural resource protection clearly is one of the more difficult areas of public policy. As wetlands restoration and enhancement projects begin the design phase, there should be better assessment of the opportunities and constraints for improving public access. Based on the discussions of Goals Project participants, agencies responsible for planning or authorizing public access facilities should:
Several species of exotic plants and animals exist in the baylands ecosystem. These species have the potential to alter the ecosystem or to seriously reduce populations of endemic plants and animals. The control of exotic invasive plants is of increasing concern, given their potential to dramatically affect habitat structure and reduce wildlife support. There are several exotic plant species that are causing problems. The spread of smooth cordgrass gives cause for alarm as it could effect large-scale impacts to the ecosystem by converting mudflat to dense tidal marsh of relatively low habitat value for many species. Peppergrass is displacing native plant species on levees and is spreading into brackish marshes. Giant reed threatens riparian habitats as it displaces native vegetation and reduces habitat quality. There needs to be a major commitment to control the spread of smooth cordgrass before it becomes established throughout the South Bay. Control should begin immediately; unless this is done, tidal marsh restoration will likely lead to the spread of this exotic plant species, and the resulting large stands of smooth cordgrass on tidal flats will undermine restoration objectives to improve habitat conditions for many fish and wildlife species dependent on native tidal salt marsh. Tidal marsh restoration projects between the Oakland Bay Bridge and the Dumbarton Bridge should have a plan and a budget to control smooth cordgrass as part of the restoration process. Efforts to control other invasive plant species including dense-flowered cordgrass (currently limited to Richardson Bay and Point Pinole), peppergrass, and giant reed also should be pursued. Exotic animal species are also of concern, especially those that are effective predators on native species. With many of the Bay Area's natural habitats disturbed or lost, predation by mammalian predators on several endangered species has become a crucial management issue. The red fox is an introduced predator that threatens the survival of the endangered California clapper rail and severely reduces populations of other native ground nesting birds. Red fox predation on the clapper rail is especially severe because the two species did not evolve together. Also, the rail's tidal salt marsh habitat is greatly reduced in area and is highly fragmented by levees which provide easy access for foxes. Cats are another especially effective mammalian predator on baylands wildlife, particularly on the California least tern; cat control near tern colonies is critical for this species' survival in the Bay. Urban development and its associated infrastructure contribute to predator problems. Developments in close proximity to marshes and other baylands habitats provide conditions suitable for terrestrial predators such as red fox, dogs, cats, rats, raccoons, and opossums. The presence of power poles, lighting fixtures, and landscaping in or near marshes enhances habitat for avian predators such as raptors and ravens which prey on snowy plovers, terns, and other bird species. In the future, projects constructed near the baylands should incorporate measures to minimize predator habitat. Habitat restoration that increases the area of tidal marshes, reduces their fragmentation, and removes predator travel corridors will reduce the vulnerability of native species to predation by exotic predators. This could lessen the amount of active predator control needed to protect endangered, threatened, and other vulnerable species. However, it is expected that some level of predator control will continue to be necessary to maintain some Bay Area wildlife species because of the proximity of urban areas to the baylands, the need to maintain existing flood control channels and levees (features that provide habitat for predators), and the difficulty of eliminating exotic predators. One possible management technique that could augment existing predator control programs in the South Bay is the re-establishment of coyote populations. Coyotes may help control red fox and other similar predators; however, this technique should be pursued very carefully in order to be certain that it would not adversely affect the wildlife species we are trying to protect, or create additional problems. Over a long period, a variety of introduced estuarine fish and invertebrates has become established in the Bay. Many of these species were transported in ship ballast water. It is probably not possible to control these species, but efforts should be directed toward preventing the introduction of additional species. The most effective way to accomplish this is by prohibiting the discharge of ship ballast water in the Bay.
Mosquitos are one of the many groups of animals that occur in the baylands ecosystem. Certain mosquito species transmit diseases, the most important of which are those caused by encephalitis viruses. Although clinical cases of encephalitis have rarely been reported in recent years, the virus is still detected annually in wild birds, in sentinel chickens, and in mosquito populations. The primary goal of mosquito abatement districts is to keep mosquito populations below threshold levels for disease transmission to humans, and to reduce nuisance problems that can impact recreational, economic, and agricultural activities and create public distress. Mosquitos rarely occur in significant numbers in tidal marshes that have full tidal action. But they can occur in large numbers in seasonally ponded wetlands without water control capacity, in tidal areas that hold water between tides, and in managed wetlands with inadequate infrastructure. The design of wetlands restoration and enhancement projects should include input from the local mosquito abatement district in order to prevent or discourage the buildup of mosquitos. Wherever possible, designs should emphasize deep water, especially on the down-wind side; open water with little or no vegetation; long fetch for waves; permanently flooded areas for predator refugia; and water control capacity. In addition, designs should incorporate a wide buffer between wetlands (especially seasonal ponds) and residential areas, and provide access points for mosquito surveillance and control. Once the project is constructed, site management staff should maintain good communication with the mosquito abatement district regarding water levels, predator abundance, and observations of mosquito larvae or adults. The managing entity also should budget funds for mosquito control, especially for lands that pay no property taxes, for projects with extensive changes in habitat type, and for projects near residential areas.
Freshwater inputs to the Bay are critical to the healthy functioning of the baylands ecosystem. The Bay is a very different place today than it was historically with regard to freshwater inflows. Diversions from the Sacramento and San Joaquin rivers have dramatically changed the flow and salinity patterns of the estuary, particularly in Suisun Bay. In addition, diversions of water from local streams have altered the salinity gradients where they flow into the Bay. Some of the water that is diverted from the Bay's streams returns to it in the form of large inputs of year-round freshwater flows from municipal wastewater treatment plants; these flows are changing the habitat type and function of tidal marshes. To the extent possible, the volume and timing of freshwater flows to the Bay should reflect historical or natural conditions under which the baylands habitats and animals developed. Increased freshwater flows in tributaries as large as the Sacramento River or as small as the intermittent streams of the South Bay would improve habitat diversity and function.
In developing the goals it became apparent that many valuable wetlands used to exist outside of the baylands, particularly vernal pools and other seasonal features in moist grasslands and riparian vegetation adjacent to streams. Although most of these wetlands have been affected by agriculture, flood control, or other development, there are many sites that could be restored or enhanced. Improving these sites could help replace some of the habitat functions that will be lost as diked areas within the baylands are restored to tidal marsh. The first step in improving the wetlands outside of the baylands should be a detailed inventory of their location and condition. Attention should focus on vernal pools and other seasonal wetlands, as many of these support unique plant and animal species. Likewise, riparian corridors should be inventoried. Measures should be taken to protect these areas before they are further degraded or lost.
Private lands around the estuary provide valuable habitat for fish and wildlife. For some of these lands, the Goals Project is recommending habitat enhancements. For other lands, it is recommending habitat conversion, mostly to tidal marsh. Project participants agree that habitat changes should occur only with the consent of property owners; they also recognize that the majority of lands around the estuary are privately held. Therefore, attaining the Project's long-term vision will require cooperation of private landowners. Without better incentives than are available now, there will be little reason to expect private landowners to improve wetlands on their lands. Incentives for wetlands restoration or enhancement might include conservation easements, land purchase and lease-back programs, funding for maintaining infrastructure such as levees and water control structures, and funding to pay for reduced crop production. Also, some landowners have indicated interest in some kind of regulatory streamlining in return for increasing wetlands habitat functions on their properties. Landowners should be paid a fair value for lands that are slated for a change, such as tidal marsh restoration or conversion to managed saline ponds, that would preclude existing productive uses. There are many ways that the public and private sectors can work more collaboratively to improve habitats in the coming years. One of the first actions to be undertaken in implementing the goals should be to find out what the landowners are willing to do to improve habitats, and to identify the financial and regulatory tools that may be used to facilitate this.
Implementing the goals recommendations will require major land acquisitions. It will be extremely important for parties interested in acquiring lands to be able to appraise them in a way that meets the expectations of a willing land owner. Currently, this is problematic. Land values vary widely within various parts of the baylands. They are influenced by location, land use designations, current use, and demand. In the South Bay, land valuations for wetlands have ranged from $6,000 to $15,000 per acre during the past several years. These prices reflect the value of land for mitigation, comparative sales prices, the proportion of the site that is upland, and the development potential (proximity to infrastructure). The presence of uplands on a parcel in close proximity to infrastructure significantly increases the value of the parcel's wetlands. In San Pablo Bay, most of the baylands are valued much lower than comparable lands in the South Bay. This is because the land is zoned as agriculture or open space, there is little development pressure, and local governments do not encourage development in areas that are away from existing infrastructure. The baylands are managed mostly for relatively low value oat hay production and grazing. Appraised values range from about $1,000 to $3,000 per acre. In Suisun Marsh, property values are similar to those in the San Pablo Bay area. Lands within the Suisun Marsh Preservation Area reflect the value of land paid for duck clubs or hunting lands. Land use other than for wetlands management or grazing is restricted. The valuation of lands in San Pablo Bay and Suisun Marsh will be pivotal to the ultimate implementation of the goals recommendations. Landowners view the prices currently offered for their lands as a pittance compared to the open space and habitat values that society seems to place on them. Resolving this issue immediately and fairly must be a high priority of the agencies.
Undertaking projects to implement the recommendations in this report will require numerous activities in the baylands, its tributaries, and other adjacent areas. Levees will need to be built or removed, water control structures moved, channels cut, and roads relocated. Many of these activities will require authorizations from regulatory agencies. Federal, state, and local agencies all have a role in regulating wetlands projects in the baylands ecosystem. The federal government oversees the most comprehensive wetlands regulations, and the federal agencies with primary regulatory roles are the National Marine Fisheries Service, Natural Resources Conservation Service, United States Army Corps of Engineers, U.S. Environmental Protection Agency, and U.S. Fish & Wildlife Service. State agencies with regulatory roles in the baylands include the San Francisco Bay Conservation and Development Commission, California Department of Fish and Game, San Francisco Bay Regional Water Quality Control Board, California State Lands Commission, and SWRCB. Local government city and county governments and special districts are responsible for a variety of policies that affect the baylands. As public and private entities begin to implement the recommendations in this report, they will need to obtain approvals for specific projects from the regulatory agencies. Most entities that undertake wetlands projects do not have the staffing or budgets to spend years dealing with inconsistent and unpredictable permit requirements. If the regulatory agencies really want to see the goals recommendations implemented, they must begin discussing how they can deal with project proposals in an integrated, coordinated way and, as necessary, adjust their policies and regulations to actually facilitate, rather than hinder, wetlands restoration.
There are several agencies and other organizations that have begun, or will soon begin, to undertake specific, large-scale ecological planning efforts in the Bay Area. These include the San Francisco Bay Conservation and Development Commission, San Francisco Bay Joint Venture, California State Coastal Conservancy, California State Department of Water Resources, U.S. Fish & Wildlife Service, U.S. Environmental Protection Agency, and others. Although the purpose, geographic scope, and products of these efforts varies greatly, five in particular will likely utilize the Goals Project's recommendations.
The San Francisco Bay Joint Venture was initiated in 1996. It is a public-private partnership that seeks to promote the acquisition, restoration, and enhancement of Bay Area wetlands and associated habitats. It is one of 15 joint ventures that operate under the auspices of the North American Waterfowl Management Plan which was signed by the United States, Canada, and Mexico. It includes partners from public agencies, environmental organizations, hunting and fishing groups, the business community, local government, and landowners. Joint Venture partners currently are preparing an implementation strategy that is scheduled for release in the Fall of 1998. The strategy will guide the Joint Venture as it undertakes specific wetlands projects, and it will include habitat goals that are derived from the recommendations of the Goals Project.
The U.S. Fish & Wildlife Service is preparing recovery plans for Central and Northern California tidal marsh and for the Pacific Coast population of the western snowy plover. The tidal marsh plan will revise and expand the existing recovery plan that was prepared several years ago and which is still in force for the California clapper rail and salt marsh harvest mouse; it will include recovery actions for these species and for several others. The western snowy plover recovery plan will be the first for that species in the Bay Area. Each of these recovery plans will identify the actions necessary to achieve self-sustaining, wild populations of listed species so they will no longer require protection under the federal Endangered Species Act. These recovery plans are scheduled to be available for public review this winter. Many members of the Goals Project have participated, or are currently participating, on recovery teams. As a result, many of the concepts and general recommendations in this report likely will be reflected in the recovery plans. However, it is important to note that the recovery plans are aimed at restoring a limited number of species, while the goals seek to describe the habitat conditions necessary for a much larger and more diverse group of organisms. Accordingly, while the recovery plan actions will likely incorporate the general habitat recommendations developed by the Goals Project, their site-specific actions may differ.
Soon after the year 2000, the U.S. Fish & Wildlife Service is scheduled to begin preparing a Comprehensive Conservation Plan (CCP) for the San Francisco Bay National Wildlife Refuge Complex. Through a process of public involvement and consultation with wildlife biologists and wetlands scientists, the CCP will identify wildlife management objectives, amounts and types of wetlands to be restored, and specific restoration projects to accomplish these objectives. The CCP will provide site-specific analysis and will incorporate funding realities and engineering considerations that are beyond the scope of the Goals Project. As a result, the configuration, location, and types of wetlands to be restored on Refuge lands in the North Bay and in the South Bay may differ from the site-specific recommendations presented in this report.
In 1997, the State Legislature established the San Francisco Bay Area Conservancy Program. The Coastal Conservancy implements this program and is cooperating with governmental agencies, nonprofit land trusts, and other interested parties to identify and adopt long-term resource and outdoor recreational goals for the nine-county Bay Area. These goals will be embodied in a plan. Although the program's scope includes all lands within the immediate Bay watershed, within the area of the Baylands ecosystem, the Conservancy will develop resource and recreational goals based on the Goals Project's habitat recommendations.
As described in Chapter 2, the San Francisco Estuary Project's Comprehensive Conservation and Management Plan calls for the development of a regional wetlands management plan. The purpose of the plan will be to protect, enhance, restore, and create wetlands in the Bay-Delta estuary. Plan preparation is scheduled to begin in the Fall of 1998, soon after the goals are completed. The plan will build upon and complement ongoing wetlands planning efforts and, among other actions, seek to develop a coordinated way to implement the Goals Project recommendations. This summer and early fall, staff of the San Francisco Bay Regional Water Quality Control Board and U.S. Environmental Protection Agency will develop a scope for the wetlands plan. Included in the scope will be a list of needed plan components, a process for developing these components, a timeline, and procedures for involving public and private stakeholders. Scope development will be undertaken in consultation with the Estuary Project's Wetlands Subcommittee and others.
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The San Francisco Estuary Baylands Goals Site is housed at the San Francisco Estuary Institute.
The San Francisco Estuary Baylands Goals Site is mirrored at the California Environmental Resources Evaluation Center.
San Francisco Estuary Institute Website contact: todd@sfei.org.
San Franicisco Estuary Baylands Goals Website contact: zoltan@sfei.org.
This page was last built on Thu, Sep 3, 1998 at 7:57:14 AM.
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