experiences in nutrient pollution control planning, implementation and evaluation in the chesapeake...
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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
Thomas Simpson, University of Maryland and The World Bank Group
Regional Conference on Nutrient Pollution ControlIn The Danube-Black Sea Basin
3-6 October, 2006Chisinau, Moldova
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
Maryland
Delaware
New York
District of Columbia
Virginia
West Virginia
Pennsylvania
The Chesapeake Bay Watershed
Chesapeake Bay Watershed Boundary
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
Agriculture37%
Urban Runoff16%
Septic4%
Atmospheric Deposition to Surface
Waters8%
Point Source21%
Forest14%
Nitrogen Sources
Agriculture43%
Urban Runoff26%
Atmospheric Deposition to Surface
Waters8%
Point Source21%
Forest2%
Phosphorus Sources
Nutrient Sources toChesapeake Bay
Source: US EPA, Chesapeake Bay Watershed Model, 2004
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?)
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
CBC
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
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
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
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?)
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
Nitr
ogen L
oad (
millio
n lb
s/y
r)
NitrogenGoal
0
5
10
15
20
25
30
1985 2000 2003
Pho
spho
rus
Load
(m
illion
lbs/
yr)
PhosphorusGoal
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
Nutrient Loading Allocation Approach
By 9 major tributary basins
...then 16 major tributary basins by
jurisdiction
…then 37 state-defined tributary
strategy sub-basins
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
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
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”
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
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
Load needed to remove nutrient impairment
Nitrogen Loads Delivered to the Chesapeake Bay
284.8275.8
0
50
100
150
200
250
300
2000 Progress 2001 Progress
(million
lb
s/y
ear)
Nitrogen loading goal is 175 Million pounds per year
Lesson Learned: Using model output and practice efficiencies to estimate reduction progress
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
INNOVATION INAGRICULTURAL CONSERVATIONFOR 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
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
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
Agricultural Pollution Controls
(Weighted impact of practices reported as implemented)
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)
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
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
Nitr
ogen L
oad (
millio
n lb
s/y
r)
NitrogenGoal
0
5
10
15
20
25
30
1985 2000 2003
Pho
spho
rus
Load
(m
illion
lbs/
yr)
PhosphorusGoal
1985 – 2005
Decreasing
No significant trend
Increasing
Nitrogen in Rivers Entering Chesapeake Bay:
Flow Adjusted Concentration Trends
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
Lo
ad
(p
ou
nd
s)
Total Bay Load 10-Year Rolling
Adapted from Boynton and CBPData by Street and Simpson
Dissolved Oxygen: Three-Year Assessment
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
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
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?
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
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