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transcript
Evaluating the effectiveness of wetlands and other BMPs in improving water
quality in tile-drained subwatersheds of the Mackinaw River
Krista Kirkham The Nature Conservancy
I-55
Bloomington-
Normal
Peoria
Pekin
I-39
I-74
N
Mackinaw River Watershed
Why Agriculture?
46-51% of undeveloped land in US in agriculture1
Almost 80% of land in Illinois is in agriculture
Generates $9 billion annually (~40% corn, 35% soybeans, 25% livestock)2
~90% of land in McLean County is in agriculture3
1USDA, 2Illinois Dept. of Agriculture, 3University of Illinois Extension Service
Environmental concerns from modern agriculture
Intensive conversion of the original landscape (
Mackinaw River, IL
Root River, MN
Boone River, IA
River restoration in agricultural landscapes
Pecatonica River, WI
Mackinaw River, IL Mackinaw River, IL
60-70 fish species 25-30 mussel species
High quality stream segments
~ 90% agricultural (corn, soybeans)
I-55
Bloomington-
Normal
Peoria
Pekin
I-39
I-74
N
Demonstration Farm
Mackinaw River Watershed Program Sites
Paired Watershed
Drinking Watersheds
Project
Paired Watershed Project: Phase 1 (1999-2006) Objectives: • Measure effectiveness of outreach on implementation of best management practices (BMPs) • Measure watershed-scale effectiveness of BMPs on water quality, hydrology, and biodiversity • Document what encourages and discourages producers and landowners from adopting BMPs (Lemke et al., 2010 JSWC 65:304-315)
• Outreach was conducted by a local landowner and
farmer in the treatment watershed from 2000 to 2003
• Outreach was conducted using one-on-one interviews,
workshops, demonstrations, flyers and newsletters
• Landowner surveys were conducted in 2000 and in
2003
Frog Alley: Reference
• Biotic surveys (seasonal): Macroinvertebrate, Fish, Mussel, Habitat • Hydrology: Stage height at D sites • Water quality: Temp, Oxygen, Conductivity, Turbidity @ D sites Nutrients: biweekly (NH4
+, NO2-, NO3
-, SRP, TP) Total Suspended Sediment (TSS): biweekly Storm Events for Nutrients and TSS @ D sites
Mackinaw River
Bray Creek: Treatment
D
U U
D
Methods:
p=0.047
p=0.004
p=0.007
Lemke et al., 2011 JEQ 40:1215-1228
Year
0.1
0.3
0.5
0.7
0.9
03 04 05 06 07 08
Tota
l Ph
osp
ho
rus
(mg
/L)
Treatment
Reference
0
5
10
15
20
25
30
35
99 00 01 02 03 04 05 06 07 08
Nit
rate
-nit
roge
n (
mg
/L)
Downstream Sites: Biweekly
Lemke et al., 2011 JEQ 40:1215-1228
Downstream sites: Biweekly Nitrate-N (mg/L)
(expectation )
-15
-10
-5
0
5
10
Trea
tmen
t N
O3-
-N m
inu
s R
efer
ence
NO
3--N
(m
g/L
)
99 00 01 02 03 04 05 06 07 08
Water Year (Oct 1 – Sept 30)
R2=0.009, p=0.16
Lemke et al., 2011 JEQ 40:1215-1228
-0.1
0.0
0.1
0.2
0.3
Trea
tmen
t TP
min
us
Ref
eren
ce T
P (
mg
/L)
2003 2004 2005 2006 2007 2008
Year
Downstream Sites: Biweekly Total Phosphorus (mg/L)
(expectation ) R2=0.013, p=0.10
Lemke et al., 2011 JEQ 40:1215-1228
Paired Watershed Project Results: 1999-2006
• Outreach works • No nutrient/suspended sediment reduction • No impact on hydrology or biota
Need to better retain runoff, especially from tile drainage
Source: Sugg, Z. 2007. Assessing U.S. Farm Drainage: Can GIS Lead to Better Estimates of Subsurface Drainage Extent? World Resources Institute, Washington D.C.
0% - 6% 7% - 16% 17% - 32% 33% - 51% 52% - 82%
Percent Total County Land With Subsurface Tile Drainage
McLean County, IL
Potential Nitrogen Fertilizer Loss from Farm Fields, Based on Production of 7 Major Crops
Source: Natural Resources Conservation Service - National Resources Inventory
Paired Watershed Project Results: 1999-2006
• Outreach works • No nutrient/suspended sediment reduction • No impact on hydrology or biota
Need to better retain runoff, especially from tile drainage
WETLANDS
1 0 1 2 M i l e
H R U w i t h N o W e t l a n d
H R U w i t h W e t l a n d
S t r e a m s
N
Where will wetlands be most effective at improving water quality?
Reference (Frog Alley)
Treatment (Bray Creek) From Bekele et al., 2010
Predicted sites for constructed wetlands for 25-26% reduction in total pollutants
Watershed Hydrologic Model – Illinois State Water Survey
74 hydrologic units 82 hydrologic units
8-in 6-in
8-in
6-in
6-in
12-in
6-in
1 0 1 2 M i l e
H R U w i t h N o W e t l a n d
H R U w i t h W e t l a n d
S t r e a m s
N
Reference (Frog Alley)
Treatment (Bray Creek) From Bekele et al., 2010
Predicted sites for constructed wetlands for 25-26% reduction in total pollutants
Watershed Hydrologic Model – Illinois State Water Survey
74 hydrologic units 82 hydrologic units
What size of wetland is most effective at reducing nutrients in tile runoff?
3% 6% 9%
Cumulative 5-year Monitoring Results
Percent of drainage area
Removal NO3-N: 19-47% ORP: 49-58%
N
NRCS Conservation Innovation Grant 2011-2013
How do winter cover crops influence nutrient export from tile-drained farmland?
N
USGS gaging stations
Money Creek
Bray Creek
Frog Alley
Six Mile Creek
Lake Evergreen Lake Bloomington
McLean County
Demonstration Farm
Mackinaw River Watershed
Apply constructed wetlands to address drinking water supply nutrient concerns
Mackinaw Drinking Watersheds Project
Precision conservation and monitoring: (1) Using GIS, aerial topography, and infrared photography to map existing tile drainage patterns and placement in the watersheds (2) Placement of constructed wetlands in locations where they will effectively retain agricultural tile drainage water and reduce nitrates (3) Monitor wetlands effectiveness (nutrients, hydrology)
Use of Farm Bill programs: Farmable Wetlands Program (CP39) within the Conservation Reserve Program (50% c/s; 40% PIP; $100/acre SIP; CRP rental payments + 20%)
Agricultural agencies: Outreach (SWCD); Initial survey, site selection, and wetland design (NRCS); Sign-up process (FSA)
• Innovative partnerships: The Nature Conservancy, City of Bloomington, Environmental Defense Fund, NRCS, SWCD, FSA, University of Illinois, Illinois State University, local farmers and landowners
Drinking Watersheds Project: Updates
Memorandum of Understanding (MOU) signed between City of Bloomington, TNC, and EDF
Awarded National Conservation Innovation Grant (USDA) for $536,173 over 3 years Monitoring (equipment and personnel)
Agricultural nutrient management
Economic analysis: gray vs. green infrastructure
Wetlands 3x cheaper in removing nitrogen
VISION FY12-14: Diverse habitats and native species; Acceptable hydrologic, sediment and nutrient balances; Increase conservation impact beyond the places we work
Applicability beyond the Mackinaw River for sustainable conservation and agricultural production
Paired Watershed Research
Research and Demonstration Farm
● Outreach
● Partnerships
● Scientific credibility
● Economic incentives
● Targeted approach
Bloomington Drinking Watersheds
● Integrating human and environmental interests
● Implementation and measures of multiple conservation practices
Mackinaw River Program
● Watershed-scale measures
Collaborators, Partners and Funding Sources: Natural Resources and Conservation Service (NRCS) Soil and Water Conservation District (SWCD) University of Illinois at Champaign-Urbana (UIUC) Environmental Defense Fund (EDF)/Walton Family Foundation City of Bloomington, Illinois World Wildlife Foundation Private landowners and producers Illinois State University (ISU) Monsanto DuPont -Pioneer Lumpkin Family Foundation Illinois State Water Survey (ISWS) AGREM LLC Illinois Department of Natural Resources (IDNR) Southern Illinois University (SIU) Ducks Unlimited (DU) Illinois Natural History Survey (INHS) Illinois State Geological Survey (ISGS) Illinois Environmental Protection Agency (IEPA) United States Environmental Protection Agency (USEPA) United States Department of Agriculture (USDA) Kellogg Foundation; Mackinaw River Partnership
Questions?
Goolsby and Pereira, 1995
Nitrogen application rates (tons/square mile)
McLean County, IL