The document outlines a nutrient management strategy for Falls Lake in North Carolina. It aims to decrease nitrogen levels by 40% and phosphorus by 77% to improve water quality. The strategy focuses on new development, existing development, agriculture, and point sources as sources of nutrient pollution. A cost-benefit analysis found that while the strategy's costs exceeded its benefits, economic analyses of other nutrient management plans have shown benefits outweighing costs. Future efforts should detail the methodology and timeframe more clearly.

1. Nutrient Management Strategy for
Falls Lake
Ariel Atkinson
James Kribs
James Mattice

2. Outline
• Background
• Costs and Benefits
– New development
– Existing development
– Point Sources
– Agriculture
– Drinking Water
– Recreational and Other Benefits
• Cost/Benefit Analysis Results
• Sensitivity Analysis
• Conclusions

3. Goals of the NMS
• Decrease Nitrogen levels by 40% and
Phosphorus by 77%.
• Improve Water Quality Designation (Impaired
to Normal)
• Protect recreational and ecological value;
reduce drinking water treatment costs

4. Background
• Other nutrient management project have
been started successfully in the area
• Rules consist of two rule amendments and
nine new rules
• Rules apply to six counties and eight
municipalities
• Rules were adopted on November 19th, 2010

5. Background
• Rules focus on sources of nutrient pollution
including: new development, existing
development, agriculture, and point sources

6. Analysis
• Assess Costs
– Planning and Water Quality Monitoring
– New development
– Existing Development
– Point Sources
– Agriculture
• Assess Benefits
– Reduced/Avoided Drinking Water Treatment Costs
– Recreational
– Other Benefits

7. New Development
• As part of the Falls Lake
Nutrient Management
Strategy, new
development must:
– Institute nutrient control
on-site
– Purchase credits to offset
their production
– Only applicable to
properties larger than
5000 sq. ft.

8. New Development
TN (lbs/year)
Cost of removal of
TN per year TP (lbs/year)
Cost of removal of
TP per year Total cost per year
For the Eight
Municipalites 20337 $150,410 1419 $141,024 $142,442
For 3 Rural
Counties (Person,
Franklin, Granville) 134197 $992,523 9523 $946,732 $956,255
For 3 Urban
Counties (Wake,
Durham, Orange) 415548 $3,073,395 29505 $2,933,233 $2,962,738
Total 570082 40447 $4,061,435
Amt of reduction 342049 24268
Goal Level 228033 16179
Total Cost of TN
and TP removal $121,843,062

9. Existing Development
• Each county or municipality must institute a plan for
regulating nitrogen and phosphorus in stormwater
runoff
– Also, they must monitor their pollutant levels
• Any existing plan must attempt to reach the
recommended levels according to what is
“economically and technically feasible”

10. Existing Development
TN (lbs/yr) TP(lbs/yr)
Current level 1141667 152174
Percentage from
Development 13% 5%
Current load from
Development 148417 7609
Percentage Reduction Goal 40% 77%
Reduction Amount 59367 5859
TN TP Total
Cost of Reduction per year $1,097,690 $832,052 $1,929,742
Cost of Reduction for 30
year plan $29,637,621 $22,465,403 $52,103,024

11. Point Sources
Dischargers TN allocation(lbs/yr) TP allocation (lbs/yr)
Large 95858 5228
Small 1052 175
Total 96910 5403
Total Reduction per year 64607 18088
Cost of Reduction per year $1,194,577 $2,568,901
Total Cost of Reduction $35,837,318 $77,067,030
Total Cost of TN and TP Reduction $112,904,348

12. Agriculture
• Fertilizers and animal waste contribute
heavily to a farms total pollution.
• Runoff leads to streams and rivers which
lead into the lake.
• A riparian buffer 10 meters wide will filter
much of this waste before it reaches water.

13. Agriculture
Removal
Efficiency(lbs/acre/yr)
Stage 1 Reduction
(lbs/yr)
Amt of Buffers Needed
to Reach Stage 1
Reduction(acres)
TN 21 66217 3153
TP 4 28000 7000
Stage 2 Reduction
(lbs/yr)
Amt of Buffer Needed
to Reach Stage 2
Reduction(acres)
TN 21 132433 6306
TP 4 53900 13475
Stage 1 Stage 2 Both Stages
Cost of Buffer
Construction $2,555,000 $2,363,375 $4,918,375
Maintenance Cost $766,500 $472,675 $1,239,175
Opportunity Cost of
Land $28,672,000 $26,521,600 $55,193,600
Total Cost $31,993,500 $29,357,650 $61,351,150

14. Drinking Water Benefits
• The levels of nitrogen and phosphorus in
Raleigh’s drinking water will not change as a
result of this study, but will reduce cost of
treatment
• The amount of treatment required to achieve the
1mg/l of N and 1µg/l (1/1000 mg) of P

15. Drinking Water Benefits
Year of the
Program
Consumption
(gallons)
Cost of Removing
TN and TP
w/NMS
Cost of Removing
TN and TP @
Current Levels of
Pollution Benefit of NMS
Discounted
Benefit of NMS
0 17646008160 $277,384 $3,673,336 $3,395,952 $3,395,952
1 18950606928 $277,362 $3,673,313 $3,395,952 $3,173,787
2 20255205696 $277,340 $3,673,291 $3,395,952 $2,966,156
3 21559804464 $277,317 $3,673,269 $3,395,952 $2,772,108
⁞ ⁞ ⁞ ⁞ ⁞ ⁞
28 54174773664 $276,763 $3,672,714 $3,395,952 $510,759
29 55479372432 $276,741 $3,672,692 $3,395,952 $477,345
30 56783971200 $276,718 $3,672,670 $3,395,952 $446,116
Total Benefit over
30 yrs $105,274,499 $45,536,455

16. Recreational Benefits
• Travel Cost Study
done
• Evaluate how
changes in water
quality correlated
with changes in
the amount of
trips made and
the WTP per trip
to Falls Lake for
recreation

17. Other Benefits
• Decrease in Other
Types of Pollution
• Improved Aesthetics
• Impact on Public
Health
• Ecological Benefits
• Increased Property
Values

18. Results of Cost/Benefit Analysis
Costs of NMS Cost
Planning and Monitoring $854,700
New Dev'p Stormwater Management $293,131,625
Existing Dev'p Stormwater Management $52,103,024
Point Source Loading Reductions $112,904,348
Agricultural Loading Reductions $61,351,150
Total Cost $520,344,847
Benefits of NMS Benefit
Recreational Benefits $241,000,000
Reduced Drinking Water Treatment $45,536,455
Avoided Upgrade in Treatment (only avoided construction costs) $120,000,000
Others(Aesthetic, Ecological, Property Values, Public Health) ---
Total Benefit $406,536,455
Net Benefit -$113,808,392

19. Sensitivity Analysis
• Changing the discount rate effects the results,
but never results in the costs outweighing the
benefits
• All population growth was assumed to be
linear
• Property values were assumed to be constant
• Cost of reducing nutrient pollution was
assumed to be at a constant rate ($/lb) for
development and point sources
• Technological Advances

20. Conclusions
• While the costs exceed the benefits, due to
uncertainty and sensitivity of the analysis, it is
not recommended to accept or reject these
rule changes
– Economic Analysis of other Nutrient Management
Plans have shown benefits outweigh costs
– Future efforts should focus on detailing the
methodology and timeframe

21. References
• Army Corps of Engineers- Wilmington District. (2008, January 18). Falls Lake. Retrieved from Army Corps of Engineers- Wilmington District:
http://www.saw.usace.army.mil/falls/index.htm
• Barnes, S. (2010, September 10). Project Description. Retrieved from Falls Lake Restoration Project: http://www.fallslakestakeholder.org/
• Bellinger, W. K. (2007). The Economic Analysis of Public Policy. New York, New York: Routledge.
• Bird, S. L., & Exum, L. R. (2010, March 4). Estimating Impervious Cover from Regionally Available Data. Retrieved October 31, 2010, from U.S. Environmental
Protection Agency: http://www.epa.gov/athens/highlights/le1335.pdf
• Brown, D., & Wilbur, S. (2008, September 11). Stormwater 201-Development Standards. Retrieved November 5, 2010, from City of Durham Stormwater Services:
http://www.ci.durham.nc.us/departments/works/pdf/sw201-5_development.pdf
• Capitol Broadcasting Company. (2010, January 5). Falls Lake pollution could require new treatment plant. Retrieved from WRAL.com:
http://www.wral.com/news/local/story/6746623/
• Energy Information Administration. (2006, November 27). Summary Table for All Buildings. Retrieved November 5, 2010, from U.S. Energy Information
Administration: http://www.eia.doe.gov/emeu/cbecs/cbecs2003/detailed_tables_2003/2003set1/2003pdf/a1.pdf
• Herrera Environmental Consultants. (2003). Green Lake Alum Treatment Study. Seattle. Wa: Seattle Department of Parks and Recreation.
• Huisman, J. (2010, March). 15A NCAC 02B.275-283. Retrieved November 5, 2010, from Falls Lake Stakeholder Project Online Wiki:
http://fallslakestakeholder.wikispaces.com/Draft+Rules
• Huisman, J. (2010). Overview of Falls Lake Nutrient Strategy. NC Division of Water Quality, Planning Section, Raleigh.
• Lynch, L., & Tjaden, R. (2000). When a Landowner Adopts a Riparian Buffer-Benefits and Costs. College Park, Maryland: University of Maryland.
• Municipal Support Division, Municipal Technology Branch. (2008). Municipal Nutrient Removal Technologies Reference Document. Office of Wastewater
Management. US EPA.
• NC Division of Parks and Recreation. (2010, September). Falls Lake State Recreation Area. Retrieved 10 2010, September, from North Carolina State Parks:
http://www.ncparks.gov/Visit/parks/fala/main.php
• NC Divison of Water Quality, Planning Section. (2010, June 14). Fiscal Analysis for Proposed Nutrient Management Strategy. Retrieved November 5, 2010, from
NCDENR: NC Divison of Water Quality: http://portal.ncdenr.org/c/document_library/get_file?uuid=2a29f5a4-3db1-4c63-bd63-cad51a5ac385&groupId=38364
• NC Ecosystem Enhancement Program. (2010, September 1). EEP's Nutrient Offset Program. Retrieved November 7, 2010, from NC Ecosystem Enhancement Program
Website: http://www.nceep.net/services/stratplan/Nutrient_Offset_Program.htm
• Rowe, R. (2001, May 22). Implementation of Neuse River Basin Model . Retrieved November 5, 2010, from Wake County Environmental Services:
http://www.wakegov.com/NR/rdonlyres/85E5620C-87E2-4D6B-AF88-46E6E644DB2E/0/StormwaterRules.pdf
• Schlegel, M. (2010). Project Description. Retrieved 2010, from Falls Lake Stakeholder Project.
• U.S. Census Bureau: State & County Quick Facts: North Carolinas. (2010, November 5). Retrieved November 5, 2010, from
http://quickfacts.census.gov/qfd/states/37000.html
• USDA National Agricultural Statistics Service. (2007). Table 40. Farms by Concentration of Market Value of Agricultural Products Sold: 2007. North Carolina.
• von Haefen, R. H. (2010, April 6). Preliminary Recreational Benefits Esitmates for the Falls Lake Nutrient Management Strategy. Raleigh, North Carolina: North
Carolina State University.