Experiences in Nutrient Pollution Control Planning, Implementation and Evaluation in the Chesapeake Bay Basin with Comparisons to the Great Lakes Program (Simpson)
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Thomas Simpson, University of Maryland and The World Bank Group Presented at the Black Sea – Danube Regional Conference on Nutrient Pollution Control in Chisinau, Moldova – October 2006
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Experiences in Nutrient Pollution Control Planning, Implementation and Evaluation in the Chesapeake Bay Basin with Comparisons to the Great Lakes Program (Simpson)
- 1. Experiences in Nutrient Pollution Control Planning, Implementation and Evaluation in the Chesapeake Bay Basin with Comparisons to the Great Lakes Program Thomas Simpson, University of Maryland and The World Bank Group Regional Conference on Nutrient Pollution Control In The Danube-Black Sea Basin 3-6 October, 2006 Chisinau, Moldova
- 2. Overview of Chesapeake Bay and its watershed • About 100,000 km2 land area • Bay is shallow with narrow “deep” trench • Huge land area to water volume ratio • 58% forest, 28% agricultural and 14% urban • Population is 16 million and growing • Three major animal productions regions with major nutrient imbalances • Cropping systems near Bay dominated by short/no rotation with annual crops
- 3. Maryland Delaware New York District of Columbia Virginia West Virginia Pennsylvania The Chesapeake Bay Watershed Chesapeake Bay Watershed Boundary
- 4. Eutrophication in the Chesapeake Bay • Nitrogen and phosphorus over enrichment causing excessive algal growth • Limiting nutrient for algal growth – Phosphorus in fresh to brackish water – Nitrogen in salt water (>~10ppt salinity) • Limiting nutrient for algal growth changes with location and season • Hypoxic/anoxic conditions in deep water • Limited clarity/loss of subaqueous grasses
- 5. Agriculture 37% Urban Runoff 16% Septic 4% Atmospheric Deposition to Surface Waters 8% Point Source 21% Forest 14% Nitrogen Sources Agriculture 43% Urban Runoff 26% Atmospheric Deposition to Surface Waters 8% Point Source 21% Forest 2% Phosphorus Sources Nutrient Sources to Chesapeake Bay Source: US EPA, Chesapeake Bay Watershed Model, 2004
- 6. The Chesapeake Bay Program: Chesapeake Bay Agreements 1983 General agreement to work together to restore Bay 1987 “40%” reduction in pollutant nutrient pollution by 2000 1992 Tributary specific nutrient reduction strategies 2000 Remove all nutrient and sediment impairments (by 2010?)
- 7. Chesapeake Bay Program (CBP) Partners • Signatories to all Chesapeake Bay Agreements – EPA (representing the Federal government) – Jurisdictions of Maryland, Pennsylvania, Virginia and Washington, DC – Chesapeake Bay Commission (representing state legislatures) • “Headwater” states – Delaware, New York and West Virginia – Committed to “Chesapeake 2000” water quality goals in 2001 C B C
- 8. Agreements are “voluntary” commitments by states and stakeholders • Sewage treatment plants permitted; nutrient removal had been for local impacts; Bay nutrient limits being imposed • Stormwater management permits are new but focused more on flow and sediment • Agriculture is voluntary with “cost share” to pay 50-85% of practice costs • Implementation involves political will, funding, incentives and persuasion
- 9. Executive Level Commitment and Political Support Is Critical • Agreements signed by Governors of jurisdictions and EPA Administrator for President • Executive Council meets annually to show ongoing support and announce new initiatives • Support must show in policies and be clear to Executive Branch Staff • Important to engage Executives from all watershed jurisdictions as much as possible
- 10. 1992 Tributary Strategy Amendment to Bay Agreement • Required tributary specific strategies to achieve “40%” reduction in N & P reaching Chesapeake Bay • Maryland used local Tributary Teams to develop agricultural strategies based on Best Management Practices (BMPs) • “Technical Options Team” used CBP BMP report, scientific literature and expert consensus to estimate efficiencies • BMPs and efficiencies were adapted for basin-wide use for all nonpoint sources in 1995
- 11. Chesapeake 2000 Agreement • By 2001 (2003), determine load reductions necessary to remove nutrient impairments • By 2002 (2005), develop new Tributary Strategies to achieve new goals • Implement practices to remove all nutrient impairments (by 2010?)
- 12. Nutrient Loading Goals The nutrient loads needed to remove nutrient impairments are: Nitrogen - 175 million pounds or less. Phosphorus - 12.8 million pounds or less. . 0 50 100 150 200 250 300 350 400 1985 2000 2003 NitrogenLoad(millionlbs/yr) Nitrogen Goal 0 5 10 15 20 25 30 1985 2000 2003 PhosphorusLoad(millionlbs/yr) Phosphorus Goal
- 13. Quantitative Goals Based on Resource Response Are Critical • Resource based goal should be end point • May need surrogate goals (establish nutrient goals/caps that will decrease anoxia) • Goals should be challenging but must be credible/achievable • May need milestones or interim goals with incremental strategies to achieve them • Must allocate loading goals to basin jurisdictions to allow for strategy development
- 14. Nutrient Loading Allocation Approach By 9 major tributary basins ...then 16 major tributary basins by jurisdiction …then 37 state- defined tributary strategy sub-basins
- 15. 2003 Tributary Strategies • Jurisdictions developed strategies to fully achieve “impairment removal goal” • Started with stakeholder involvement like 1993 strategies • Goals so challenging stakeholders could not agree upon strategy to reach goal • Jurisdictions included practices with high model reduction estimates at near complete levels and created some new practices (Beyond credible levels?) • Nonpoint Sources: Heavy agricultural focus but added urban controls for “equity” in some strategies • All sewage treatment plants will enhance nutrient removal
- 16. Funding and implementing agricultural practices • Society shares cost with farmer; farmer has responsibility to reduce nutrient pollution • 50-85% cost-share for practice implementation • Long history of education/demonstrations and equipment rental by public agencies to promote adoption • Increasing use of incentives to take “risks” and try new practices • Hard to get above 75% adoption in voluntary program
- 17. Funding and implementing agricultural practices (2) • New practices/systems must be demonstrated and supported by incentives before widespread adoption will occur • Need to target practices and incentives for maximum nutrient reduction • Opportunities to turn production subsidies or incentives into water quality incentives • Increased public investment will require increased farmer “proof of performance”
- 18. Jurisdictional Strategies to Achieve Goals Are Important • Realistic strategies with jurisdictional, local government and stakeholder support critical • Challenging, yet “doable” practice implementation levels needed • New practices must be acceptable or have program planned to gain acceptance • Need implementation schedule and funding plan • May need interim goals and milestones and strategies to achieve them incrementally
- 19. Best Management Practices (BMP) efficiencies are critical in Tributary Strategy development • Jurisdictions and stake holders identify practices, control measures or land use changes (all termed BMPs) that will reduce nutrient pollution and propose implementation levels of these to achieve allocation • Practices defined and assigned reduction efficiencies based on science and experience • Watershed Model scenarios are run with proposed BMP implementation and estimated efficiencies • Results estimate impact of proposed strategies • Iterative process if load allocations are not achieved
- 20. Load needed to remove nutrient impairment Nitrogen Loads Delivered to the Chesapeake Bay 284.8 275.8 0 50 100 150 200 250 300 2000 Progress 2001 Progress (millionlbs/year) Nitrogen loading goal is 175 Million pounds per year Lesson Learned: Using model output and practice efficiencies to estimate reduction progress
- 21. It became apparent that modeled load reductions were greater than indicated by monitoring data. Why? • Lag times in water and in practice implementation • Cycling of nutrients in rivers and Bay • Modeling, monitoring or calibration issues • Annual model runs using 1985-94 (now go through 2004) hydrology to get average load, not hydrology for actual year • BMP efficiencies and application assumption issues
- 22. INNOVATION IN AGRICULTURAL CONSERVATION FOR THE CHESAPEAKE BAY: EVALUATING PROGRESS AND ASSESSING FUTURE CHALLENGES T. W. Simpson and C. A Musgrove, University of Maryland; R. F. Korcak, USDA-ARS A White Paper From The Scientific & Technical Advisory Committee Chesapeake Bay Program 2003 http://www.chesapeake.org/stac/stacpubs.html
- 23. Probable sources of error in estimating BMP impacts • Limited data and/or field observation • Research/plot scale reduction efficiencies applied to w/s scale implementation • Extreme spatial variability in soils, hydrology, management, etc • Plans assumed to be implemented • Optimistic reported implementation rates • Assume proper O&M and replacement Appear to result in optimistic estimates of impact
- 24. BMP efficiency changes reduced modeled “progress” and created a substantial policy/management “crisis” but made model results closer to actual and caused change • Forum and white paper identified issues • BMP efficiency revisions made for some practices • Bay Program implemented changes for operational issues • Changes in operational assumptions are being used in calibration of new phase of Watershed Model • Project under way to revise old efficiencies and establish conservative ones for new practices • Some research being funded or prioritized in RFPs to enhance science base for BMP efficiencies
- 25. Agricultural Pollution Controls (Weighted impact of practices reported as implemented)
- 26. Use of BMP/control measure efficiencies in nutrient pollution control • Only way to estimate impact of proposed strategy/actions • Also critical to any market-based approach • Need better data on effectiveness and spatial and temporal variability but must make decisions with current knowledge • Use conservative efficiencies when extrapolating from research to watershed/operational scale • Use conservative implementation, operation, maintenance and reporting assumptions • Always easier to adjust effectiveness up than to lower it (but have never had to do this)
- 27. The Roles of Modeling and Monitoring • Modeling essential for planning/projecting – Project impact of changing land use – Estimate impacts of practices and implementation progress – Estimate efficiency of strategy scenarios • Monitoring must be primary tool to measure water quality changes – Need affordable, yet adequate monitoring – Monitoring used to calibrate model – Need monitoring at jurisdictional boundaries – Large inter-annual variability makes trends difficult to see in short term Modeling and Monitoring must be balanced but are both essential
- 28. Nutrient Loading Goals The nutrient loads needed to remove nutrient impairments are: Nitrogen - 183 million pounds or less. Phosphorus - 12.8 million pounds or less. . 0 50 100 150 200 250 300 350 400 1985 2000 2003 NitrogenLoad(millionlbs/yr) Nitrogen Goal 0 5 10 15 20 25 30 1985 2000 2003 PhosphorusLoad(millionlbs/yr) Phosphorus Goal
- 29. 1985 – 2005 Decreasing No significant trend Increasing Nitrogen in Rivers Entering Chesapeake Bay: Flow Adjusted Concentration Trends
- 30. N Loads to Chesapeake Bay - 100,000,000 200,000,000 300,000,000 400,000,000 500,000,000 600,000,000 700,000,000 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Year Load(pounds) Total Bay Load 10-Year Rolling Adapted from Boynton and CBP Data by Street and Simpson
- 31. Dissolved Oxygen: Three- Year Assessment
- 32. Summary and Comparison: Chesapeake Bay Great Lakes • N and P limited • Started in 1983, intensified in 1992 • 6 states, one country • P detergent ban and P controls at point sources most effective reduction • Nonpoint sources remain difficult • P and toxicants • Started in 1970’s • Bi-national • P detergent ban and P controls at point sources most effective reduction • Some success with toxicant reductions • Nonpoint sources remain difficult Source for Great Lakes Info: Botts and Muldoon. Great Lakes Water Quality Agreement: Its Past Successes and Uncertain Future http://www.on.ec.gc.ca/greatlakes/default.asp?lang=En&n=EB5E196D-1
- 33. Formula for success to date Chesapeake Bay Great Lakes • Team effort led by Executive level • Watershed wide (truly regional) • Adoption of common resource-based goals • Equitable allocations to jurisdictions • Science-based • Moving to adaptive science/management • Increased accountability and realism of impacts • Promotion of community • Bi-nationalism • Equity and parity in structure and obligations • Adoption of common objectives • Provisions for joint fact- finding and research • Flexibility and adaptability to changing circumstances • Accountability and openness in information exchange
- 34. Current and Future Issues and Challenges for Chesapeake Bay (and Great Lakes?) • Maintaining community of support after 20 years • Funding issues and priorities • Credibility and accountability of strategies and implementation impacts • Staged implementation plan and funds for strategies • Addressing agricultural nutrient pollution while maintaining viability of agriculture • Offsetting increases due to population growth and development and agricultural intensification • Need to evaluate/change management structure?
- 35. Keys to Successful Nutrient Pollution Control Programs • Executive level commitment and community support • Quantitative watershed and jurisdictional goals • Implementable strategies based on conservative control measure efficiency • Implementation and funding plan (particularly for agriculture) • Science based programs, targeting and adaptive management to maximize benefits and allow for adjustments and new initiatives • Patience and diligence
Notes de l'éditeur
- <number> About half of the water volume in the Bay is salt water from the Atlantic Ocean. The other half drains into the Bay from an enormous 64,000 square mile drainage basin or watershed. Ninety percent of this fresh water is delivered from five major rivers: the Susquehanna (which is responsible for about 50% just by itself), the Potomac, the James, the Rappahannock and the York. The Bay's watershed includes parts of six states: Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia, as well as the entire District of Columbia. If you are one of the 15 million people who live in the watershed, then the Bay starts in your backyard! Everyone in the watershed lives just a few minutes from one of the more than 100,000 streams and rivers that drain into the Bay. Each of these tributaries can be considered a pipeline from your community into the Bay and its rivers. Because things on land are easily washed into streams and rivers, our actions on land ultimately affect the Bay. These activities even include using cars, fertilizers, pesticides, toilets, water, and electricity. To restore the Bay, we have to be concerned about what we do in our own communities, homes, and backyards. The landscape which comprises the Bay watershed is made up of many interconnected basins, or watersheds. Within each watershed, all water runs to the lowest point - a stream, river or the Bay. On its way, water travels over the surface and across farm fields, forest land, suburban lawns, and city streets, or it seeps into the soil and travels as ground water. Large watersheds like the Chesapeake Bay are made up of many smaller watersheds across several states.
- <number> In the 1987 Chesapeake Bay Agreement, the CBP committed to reducing controllable nutrient loads 40% from 1985 level by the year 2000. In the Chesapeake 2000 agreement , the CBP committed to reduce nutrient loads further and reduce sediment loads in order to correct all nutrient and sediment-related problems in the Bay by 2010. In 2003, the CBP agreed to reduce nutrient loads so that no more than 175 million pounds of nitrogen and 12.8 million pounds of phosphorus will be delivered to the Bay in 2010 (and every year after). They also agreed to reduce land-based sediment loads so that no more than 4.15 million tons will be delivered to the Bay in 2010 (and every year after). These reductions in nutrients and sediment are expected to result in improved water quality conditions necessary to support the living resources of the Bay. At the agreed to reductions, the Chesapeake Bay Water Quality Model predicts that we will see a Bay similar to that in the 1950s. Water quality conditions necessary to protect aquatic living resources will be met in 96% of the Bay at all times, and the remaining 4% will fall shy of fully achieving water quality conditions for only four months a year. Between 1985 and 2002, annual phosphorus loads delivered to the Bay from the entire watershed (New York, Pennsylvania, Maryland, Delaware, the District of Columbia, West Virginia and Virginia) were reduced by 7.64 million pounds. Annual nitrogen loads were reduced by 59.81 million pounds and upland sediment loads by 0.79 million tons. The reductions obtained between 1985 and 2002 include off-setting a significant increase due to population growth. Maintaining reduced nutrient and sediment levels into the future will be a challenge due to expected growth in human population and shifts in animal manure nutrients and the land available for application of nutrients.
- <number>
- <number> There are some inherent limitations to the model that would indicate that our current real progress as measured in the water, is less than shown
- <number> Overview: The agricultural community is using dozens of different types of “best management practices” to reduce the amount of pollution reaching local waters and the Bay. Goal: Implement enhanced pollution controls on agricultural land in order to, by 2010, correct the nutrient- and sediment-related problems in the Bay and its tidal tributaries. Status: Since 1985, the partners have achieved about two-fifths of their implementation goal for reducing nitrogen run-off from agriculture and about half of their implementation goal for reducing phosphorus. Additional Information: In part because they are so cost-effective, the Bay jurisdictions are relying on future reductions from agricultural lands for more than half of the remaining nutrient reductions needed to meet restoration goals. The economics of agriculture require that significant funding and technical assistance will be needed for this sector to meet its restoration goals. Trends in implementation of BMPs and control technologies, and the resultant impacts on loads to the Chesapeake Bay, are useful in understanding trends in water quality and overall ecosystem health. Individual source indicators illustrate the effects of tracked historic implementation of pollutant controls and make comparisons to what is currently forecasted to be needed from the sources to meet restoration goals. Tracking and reporting these impacts is one measure used to clearly assess progress toward meeting Tributary Strategy objectives so effective management actions can be targeted (including addressing funding gaps) that ultimately achieve jurisdictional-adopted water quality standards. For additional information about the methods and data, view the data and indicator survey at http://chesapeakebay.net/pubs/2006reports/IndicatorSurvey_Reducing_Pollution_032406.doc For more information contact Jeff Sweeney at CBPO (1-800-986-7229).
- <number> In the 1987 Chesapeake Bay Agreement, the CBP committed to reducing controllable nutrient loads 40% from 1985 level by the year 2000. In the Chesapeake 2000 agreement , the CBP committed to reduce nutrient loads further and reduce sediment loads in order to correct all nutrient and sediment-related problems in the Bay by 2010. In 2003, the CBP agreed to reduce nutrient loads so that no more than 175 million pounds of nitrogen and 12.8 million pounds of phosphorus will be delivered to the Bay in 2010 (and every year after). They also agreed to reduce land-based sediment loads so that no more than 4.15 million tons will be delivered to the Bay in 2010 (and every year after). These reductions in nutrients and sediment are expected to result in improved water quality conditions necessary to support the living resources of the Bay. At the agreed to reductions, the Chesapeake Bay Water Quality Model predicts that we will see a Bay similar to that in the 1950s. Water quality conditions necessary to protect aquatic living resources will be met in 96% of the Bay at all times, and the remaining 4% will fall shy of fully achieving water quality conditions for only four months a year. Between 1985 and 2002, annual phosphorus loads delivered to the Bay from the entire watershed (New York, Pennsylvania, Maryland, Delaware, the District of Columbia, West Virginia and Virginia) were reduced by 7.64 million pounds. Annual nitrogen loads were reduced by 59.81 million pounds and upland sediment loads by 0.79 million tons. The reductions obtained between 1985 and 2002 include off-setting a significant increase due to population growth. Maintaining reduced nutrient and sediment levels into the future will be a challenge due to expected growth in human population and shifts in animal manure nutrients and the land available for application of nutrients.
- <number> Overview: Nitrogen, phosphorus and sediment concentrations are monitored near the head of tide (fall line) in eight of the Bay's major rivers, and in the non-tidal portion of the Susquehanna River in Pennsylvania. The volume of water flowing past the monitoring gauges – or river flow – is also measured. The long-term concentration trends are adjusted to reflect the changes in flow that are largely a function of annual precipitation. Since they are independent of annual variability, the flow adjusted concentration trends allow us to evaluate the success of pollution control management programs on a watershed-wide scale. Since the monitoring is conducted at the fall line, the trends do not reflect the impact of management actions in the coastal plain areas of the watershed. Status: Monitoring data from major rivers entering tidal waters of Chesapeake Bay show that flow adjusted nitrogen concentrations are decreasing in the Susquehanna, Patuxent, Potomac, Rappahannock, and James rivers. The Pamunkey (a tributary to the York) shows an increasing trend. The Mattaponi (a tributary to the York) and Appomattox show no significant trend. Additional Information: Source of data for map: USGS and Susquehanna River Basin Commission, PA. Results are shown for trend analyses using the earliest complete data set collected since 1985. Starting at monitoring sites at the top of the map and moving left to right: Towanda (on Susquehanna R.), decreasing trend in TN concentrations from 1985 through 2005. Lewisburg (on West Branch of Susquehanna R.), decreasing trend in TN concentrations from 1985 through 2005. Danville (on Susquehanna R.), decreasing trend in TN concentrations from 1985 through 2005. Newport (on Juniata R.), decreasing trend in TN concentrations from 1985 through 2005. Marietta (on Susquehanna R.), decreasing trend in TN concentrations from 1985 through 2005. Conestoga (on Conestoga R.), decreasing trend in TN concentrations from 1985 through 2005. Conowingo (on Susquehanna R.), decreasing trend in TN concentrations from 1985 through 2005. Patuxent (on Patuxent R.), decreasing trend in TN concentrations from 1985 through 2005. Potomac (on Potomac R.), decreasing trend in TN concentrations from 1985 through 2005. Rappahannock (on Rappahannock R.), decreasing trend in TN concentrations from 1985 through 2005. Mattaponi (on Mattaponi R., tributary to York R.), no significant trend in TN concentrations from 1985 through 2005. Pamunkey (on Pamunkey R., tributary to York R.), increasing trend in TN concentrations from 1985 through 2005. James (on James R.), decreasing trend in TN concentrations from 1985 through 2005. Appomattox (on Appomattox R., tributary to James R.), no significant trend in TN concentrations from 1985 through 2005. For more information contact Michael Williams, CBPO (1-800-968-7229) or Scott Phillips, USGS (410-238-4252).
- <number> Overview: Like terrestrial animals, the Bay’s fish and shellfish need oxygen to survive. During summer months, a large volume of the Bay’s water does not hold enough oxygen to support them. Over time, large-scale reductions in the amount of nutrients flowing into the Bay will help improve low oxygen conditions. Goal: By 2010, correct the nutrient and sediment-related problems in the Chesapeake Bay and its tidal tributaries sufficiently to remove the Bay and the tidal portions of its tributaries from the list of impaired waters under the Clean Water Act. Status: Water quality data gathered between 2003 and 2005 indicate that about 29 percent of the combined volume of open water, deep water and deep channel water of the Bay and its tidal tributaries met dissolved oxygen standards during the summer months. Additional Information: When assessing the Bay’s tidal water quality, federal and state regulators examine conditions over the most recent three years to help remove annual weather-driven fluctuations. To meet water quality restoration goals, monitoring data from the Bay and its tidal tributaries must attain a set of criteria measured over those three years. State water quality standards have been developed to meet the dissolved oxygen needs of the Bay’s aquatic life. The standards vary with depth, season and duration of exposure. Generally speaking, oxygen rich shallow waters are most essential in the spring during spawning season. Slightly lower dissolved oxygen levels are acceptable at other times of the year and in deeper waters. Dissolved oxygen (DO) refers to the amount of oxygen that is present in a given quantity of water and that amount must exceed certain minimum levels for a healthy and diverse ecosystem. There are several sources of DO in the Chesapeake Bay. The most important is the atmosphere where oxygen is present at concentrations very much higher than in the water. The process of atmospheric oxygen dissolving in water is enhanced by wind, which mixes the surface layer of the Bay. Two other important sources of oxygen in Bay waters are phytoplankton (single celled plants) and submerged aquatic vegetation (SAV), or underwater grasses, which produce oxygen through photosynthesis. A final major source of DO in the Bay comes from water flowing into the estuary from streams, rivers and the Atlantic Ocean. Water flowing in streams and rivers is more turbulent which promotes mixing in from the air. Ocean water generally has a higher oxygen content due to the fact that the factors that deplete oxygen are relatively small. Processes that consume DO include plant and animal respiration, the decomposition of dead plants and animals, and the oxidation of other chemicals. The amount of oxygen that can dissolve in water is strongly limited by the temperature of the water and, to a much smaller degree, by other substances dissolved in the water such as salt. The colder the water, the more oxygen it can hold. Therefore, the waters of the Chesapeake Bay have a greater capacity to hold DO during the cold winter months than they do during the summer. DO levels are the result of a complex interaction of natural processes (including how water circulates in the Bay, weather patterns, and seasonal cycles in the growth of plants and animals) and manmade influences. Some variation in DO levels occurs naturally, with low DO occurring when, or where, DO is consumed faster than it can be replaced. The human impact on DO levels is the result, principally, of nutrient pollution. The extra nutrients that we add to the Bay stimulate algae growth. Although algae are producing oxygen in the daytime through photosynthesis, respiration at night and the decomposition of dead algal cells can overwhelm the processes that add oxygen resulting in very low DO. For information about the methods and data, please refer to the Dissolved Oxygen Indicator and Data Survey available at http://chesapeakebay.net/pubs/2006reports/Indicator_Survey_Dissolved_Oxygen_Revised_MRW.doc For additional information about DO, please refer to the dissolved oxygen backgrounder available at http://www.chesapeakebay.net/pubs/doc-do_101_backgrounder.pdf For more information contact Michael Williams at CBPO (1-800-968-7229).