The Chesapeake Futures report tries to imagine what the Bay would look like in 30 years under three alternative scenarios.
Projections for this scenario are based on the assumption that recent trends observed in the last decade will continue into the future, without additional progress in restoring the Bay ecosystem.
- Sediment loads into the Bay increase from land development, the filling of Susquehanna River dams and shoreline erosion. Coupled with increased nutrient loads, water clarity in many areas is likely to decrease.
- Significant areas of tidal wetlands will be lost to sea level rise.
- As nitrogen loads creep back toward 1985 levels from population growth and development, excessive phytoplankton production will continue to lead to persistent low-oxygen conditions during the summer months.
- Bay grass acreage will contract except for tributaries with little sediment and nutrient increases.
- Much of the phytoplankton production will continue to fuel bacteria growth rather than fish and crabs.
- The biological diversity and resiliency of the Bay ecosystem will remain compromised and outbreaks of harmful algal blooms could increase.
- Fisheries crises will continue as a result of management operating in a reactive mode and the limited capacity of the ecosystem to produce valued resources.
Projections for this scenario anticipate achieving commitments in agreements signed from 1983 through 2000.
- More limited land development, improved stormwater management, and riparian buffer restoration will hold the line in sediment inputs from the watershed, but sediment from shoreline erosion will increase. Water clarity in some areas will increase as a result of decreased nutrient loadings, but not in areas near rapidly eroding shorelines.
- Significant areas of tidal wetlands will succumb to sea level rise and restrictions to their landward migration.
- Average nitrogen loads will continue their decline, eventually resulting in demonstrable reductions in excessive phytoplankton growth and severe hypoxia.
- The Bay’s food web will recover somewhat, with more of the algae production going toward fish rather than bacteria, and some bottom areas will become more suitable habitat.
- The biological diversity and resiliency of the Bay ecosystem will increase, buffering the Bay from extreme events and reducing the frequency and severity of harmful algal blooms.
- The socioeconomic value of the Bay’s fisheries will increase modestly as the productive capacity of the Bay ecosystem increases and harvests are managed in a more sustainable manner.
This scenario anticipates a widespread adoption of new technologies and aggressive actions to manage growth, restore habitat and manage fisheries.
- Highly restrictive land development, substantial retrofitting of stormwater infrastructure and the removal of sediment from behind Susquehanna River dams will result in real reductions of sediment loads from rivers. Adaptive shoreline management strategies will target protection efforts and sustain the longevity of tidal wetlands, resulting in no net increase in shoreline erosion. Water clarity in most regions of the Bay and its tidal tributaries will increase substantially because of decreased nutrient loads.
- Tidal wetlands will remain close to present total acreage levels with active management to enhance soil accretion in deteriorating marshes.
- Average nitrogen loads will decline to nearly one-half of those at the end of the 20th century, approximating levels not seen since the 1950s. The decrease will result in approximately proportional reductions in plankton productivity and substantial reductions in the extent of hypoxia, again back to the levels typical of the 1950s. Significant anoxia will occur only during flood years.
- Submerged aquatic vegetation will expand in extent almost four– or fivefold.
- Primary production — phytoplankton — will decrease by one-third or more from reduced nutrient loads, but the production of fish and crabs will increase because of expanded habitat availability and because the types of phytoplankton produced will be those more likely to go into the food chain leading to fish, rather than to bacteria.
- The health of the Bay ecosystem — its useful production, diversity and resilience — will improve even more.
- Although supplies will perpetually fall short of growing demands, the living resources of the Bay will provide more sustained and profitable benefits to society from the improved health of the Bay as well as informed, forward-looking and precautionary management of fishery resources.