Despite increasingly large investments, the potential ecological effects of river restoration programs are still small compared to the degree of human alterations to physical and ecological function. Thus, it is rarely possible to “restore” pre-disturbance conditions; rather restoration programs (even large, well-funded ones) will nearly always involve multiple small projects, each of which can make some modest change to selected ecosystem processes and habitats. At present, such projects are typically selected based on their attributes as individual projects (e.g., consistency with programmatic goals of the funders, scientific soundness, and acceptance by local communities), and ease of implementation. Projects are rarely prioritized (at least explicitly) based on how they will cumulatively affect ecosystem function over coming decades. Such projections require an understanding of the form of the restoration response curve, or at least that we assume some plausible relations and estimate cumulative effects based thereon. Drawing on our experience with the CALFED Bay-Delta Ecosystem Restoration Program in California, we consider potential cumulative system-wide benefits of a restoration activity extensively implemented in the region: isolating/filling abandoned floodplain gravel pits captured by rivers to reduce predation of outmigrating juvenile salmon by exotic warmwater species inhabiting the pits. We present a simple spreadsheet model to show how different assumptions about gravel pit bathymetry and predator behavior would affect the cumulative benefits of multiple pit-filling and isolation projects, and how these insights could help managers prioritize which pits to fill.

Anthropogenic accommodation space, or that space in the Delta that lies below sea level and is filled neither with sediment nor water, serves as a useful measure of the regional consequences of Delta subsidence and sea level rise. Microbial oxidation and compaction of organic-rich soils due to farming activity is the primary cause of Delta subsidence. During the period 1900-2000, subsidence created approximately 2.5 billion cubic meters of anthropogenic accommodation space in the Delta. From 2000-2050, subsidence rates will slow due to depletion of organic material and better land use practices. However, by 2050 the Delta will contain more than 3 billion cubic meters of anthropogenic accommodation space due to continued subsidence and sea level rise. An Accommodation Space Index, which relates subaqueous accommodation space to anthropogenic accommodation space, provides an indicator of past and projected Delta conditions. While subsidence and sea level rise create increasing anthropogenic accommodation space in the Delta, they also lead to a regional increase in the forces that can cause levee failure. Although these forces take many forms, a Levee Force Index can be calculated that is a proxy for the cumulative forces acting on levees. The Levee Force Index increases significantly over the next 50 years demonstrating regional increases in the potential for island flooding. Based on continuing increases in the Levee Force Index and the Accommodation Space Index, and limited support for Delta levee upgrades, there will be a tendency for increases in and impacts of island flooding, with escalating costs for repairs. Additionally, there is a two-in-three chance that 100-year recurrence interval floods or earthquakes will cause catastrophic flooding and significant change in the Delta by 2050. Currently, the California Bay-Delta Authority has no overarching policy that addresses the consequences of, and potential responses to, gradual or abrupt landscape change in the Delta.

The nation's estuaries are at risk of further deterioration from land use change and intensification. These risks include direct impacts on wetland habitats and stream environments and indirect impacts from nonpoint source pollutant loading. This article reports on the methods, findings, and policy implications of a major study, "The Effects of Land Use Change and Intensification on the San Francisco Estuary." By using a geographic information system (GIS), future growth scenarios were played out and the impacts on wetlands, streams, and water quality were estimated on a regionwide basis.The land use scenario developed from the General Plans of the Bay-Delta Region's 12 counties shows that the total area planned as urban use outside existing incorporated cities is 331,530 acres, an increase of 3 7%. This land use change and intensification associated with increased growth will continue to stress an overtaxed estuarine system. Results are expressed according to 14 receiving water segments and the associated 34 watersheds.Direct impacts on wetlands and strewn environment zones occur in every watershed containing these resources. We estimate that over 39,500 acres of wetlands may be.potentially impacted. Of 377,000 acres of stream environment in the 12-county study area, 28,000 acres are also subject to impacts of urbanization. Our analysis suggests that protection of farmed wetlands in the Delta and North Bay and the enhancement of biodiversity in the South Bay deserve special attention. The construction of land use scenarios for the estuary region has presented, for the first time, an opportunity to examine the cumulative contribution of nonpoint source urban runoff to the levels of pollutants in the bay and delta. To date, more modest studies in smaller urban watersheds have provided only a glimpse of the overall effect that urbanization has in a region the size of the estuary. We found that these impacts can be expected to decrease the overall water quality of the estuary.The existing system of land use planning delegates responsibility to local governments. However, of 111 jurisdictions within the estuary study region, only 18 have specific ordinances to protect streams and wetlands. We recommend that the existing system regulation and management be strengthened to protect, enhance, and restore the environmental well-being of the estuary. The results of our study suggest that improvements are needed in the goals, management strategies, and institutional arrangements now in place for the San Francisco estuary. We advance several specific management options to help frame the debate over strengthening estuarine management. In particular, we urge that a specific focus on estuarine resource protection be incorporated in any new growth management legislation enacted in California.We identify several important national policy implications arising from our study. First, we believe the potential transferability of our methodology to other estuaries should be investigated. Second, we recommend that technical workshops be convened for estuarine managers who are addressing similar management issues. Third, we recommend that policy guidance to encourage the use of watersheds and receiving waters as the unit for analysis. We also recommend that GIS-based analysis should be used to test the implications of alternative wetland definitions to inform the national policy debate.

The program in environmental planning at the University of California at Berkeley offers an example of the possibilities and challenges of work at a major American public university. This multi-disciplinary program has ties to more than a dozen allied fields. It takes an aggressive, adversarial role in the field of land planning/development and environmental management within the highly charged context of development in the far western United States. Examples of courses, research facilities and study projects are given.