Groundwater
Overview
Adams County Lake Alliance
Kevin Masarik
Center for Watershed Science and Education
Through the University of Wisconsin-Extension, all Wisconsin people can access
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Groundwater 101
Source: Unknown
Central Wisconsin
January 18, 2016
-10 °F
January 18, 2016
Wisconsin has 3 major basins
Lake Superior Basin
Basins of Wisconsin
Sub-continental Divide
Mississippi River
Basin
Lake Michigan
Basin
….regional watersheds can be further defined to show just
how local groundwater quality really is.
http://pubs.usgs.gov/circ/circ1186/pdf/circ1186.pdf
Watershed – the land area where water originates for
lakes, rivers or streams. Water flows from high
elevation to low elevation.
Runoff
Impermeable bedrock
Groundwater flow
Impermeable bedrock
Adams County
Groundwater
Flow
Lakes and Groundwater
Water quantity issues in
Wisconsin:
• Concentrated pumping of
groundwater threatens
health of nearby streams
and lakes.
• Communities have had to
locate alternative sources
of water because of
contamination in existing
aquifers.
• Some communities have
trouble extracting sufficient
groundwater because of
local geologic conditions.
Groundwater and High Cap
Wells
Effects of irrigation
50% of area irrigated
-drought stream loss:
100%
- drought water decline:
4 - 5 feet
Nitrogen Cycle
“Nitrogen is neither created nor destroyed”
http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/20528/em8954-e.pdf
Nitrogen contributes to Gulf Hypoxia
http://water.usgs.gov/nawqa/sparrow/gulf_findings/delivery.html
•
Excessive nutrients contribute to growth
of large amounts of algae that decay
and consume oxygen – hypoxia.
•
Negatively affects the economic and
ecological health of one of the nation’s
most productive fisheries.
Nitrate and Human Health
Infants and pregnant women
•
•
Methemoglobinemia or “blue-baby syndrome”
Possible correlation to central nervous system malformations
Adults
Possible correlations to:
• Non-Hodgkin’s lymphoma
• Various cancers (ex. gastric, bladder)
• Thyroid function
• Diabetes in children
*Many are statistical studies that provide correlation between nitrate and health problems
*Studies don’t always agree, but cannot say with certainty that nitrate poses no health risk.
Nitrate often indicator of other possible contaminants
(ex. other agricultural contaminants, septic effluent, etc.)
Wisconsin Groundwater Coordinating Council, 2015; Weyer, 1999
Nitrate in drinking water
• Greater than 10 mg/L
Impacted at a level that exceeds
Nitrate Nitrogen
state and federal limits for
drinking water
10
•
DO NOT give water to
infants
•
DO NOT consume if you
are a woman who is
pregnant or trying to
conceive
•
RECOMMEND everyone
avoid long-term
consumption
• Between 1 and 10 mg/L
Evidence of land-use impacts
1
0
• Less than 1 mg/L
Natural or background levels in
WI groundwater
Considered suitable
for drinking water
Nitrogen is vital to
agriculture
 Ancient civilizations farmed fertile
flood plains
 Animal manures
 Crop rotations w/legumes
 Prairies and other organic rich soils
 Industrial fixation of N leads to
commercial fertilizer and dramatic
increase in N applications
 Manure management challenging
7
N
14.01
Nitrogen
N, P, K
More
Less
Nitrogen Fertilizer Added (lb/acre)
Maximum Yield
Slope = Added Yield
Increasing
Yield or Biomass Accumulation (kg/ha)
Yield response to nitrogen
Economic Optimum
• variable from year to year
depending on energy costs, fertilizer
costs, price of commodities
0
Increasing
Fertilizer Added (kg/ha)
Fertilizer Unit
Historical Nitrogen Use
U.S. Consumption of Nitrogen Fertilizer (1960-2011)
Nitrogen (1,000 nutrient short tons)
14,000
12,000
10,000
8,000
6,000
4,000
2,000
0
1960
1970
1980
1990
2000
2010
Year
USDA Fertilizer Use and Price, 2013
http://www.ers.usda.gov/data-products/fertilizer-use-and-price.aspx
Nitrogen fertilizer recommendations for
common crops
* Legumes have symbiotic relationship with N fixing bacteria
Alternative Field Crops Manual, 1989. University of Minnesota and University of Wisconsin -Madison
Nutrient application guidelines for field, vegetable and fruit crops in Wisconsin. A2809. 2012. University of Wisconsin-Madison
Miscanthus and switchgrass recommendations: Anderson et al., 2013; McIsaac et al., 2010; Vogel et al., 2002; Arundale et al, 2014
Efficiency of plants at utilizing nitrogen –
the corn example
http://www.bae.ncsu.edu/programs/
extension/evans/ag452-1.html
http://www.youtube.com/watch?v=iFCdAgeMGOA
http://www.soilandhealth.org/01aglibrary/010137veg.roots/010137ch2.html
Comparing Annual to Perennial
Ecosystems
http://www.soilandhealth.org/01aglibrary/010137veg.r
oots/010137ch2.html
Nitrogen fertilizer use
efficiency for Midwestern
corn systems
37%
(Cassman et. al. 2002)
Mixed Native Perennial
http://soils.usda.gov/sqi/management/files/RSQIS6.pdf
Effect of cropping systems on nitrate leaching loss
in the Midwest
Cropping
systems
Corn-Corn
Annual
Corn-Soybean
Mixed
Perennial
C-S-O/A-A
Alfalfa
CRP
Switchgrass
Miscanthus
Prairie
Pasture
N Inputs
Nitrate-N
Leaching
Water
Drainage
kg N ha-1 yr-1
kg N ha-1 yr-1
mm yr-1
138
180
151-221
202
202
136-0
168-0
168-0
171-0
171-0-57-0
0
0
0
112
0
112
0
0
55
37
17-32
63
43
51
34-46
34
10-35
8-18
2
1
<1-4
2-11
2-7
<1-1
<1
1-10
193
399
63-187
590
280
226
ND
470
ND
ND
104
160
ND
52-156
ND
52-147
122
ND
Data Source
Randall et al., 1997 (1)
Masarik et al., 2014 (2)
Thomas et al., 2014 (3)
Weed and Kanwar, 1996 (4)
Randall and Iragavarapu, 1995 (5)
Randall et al., 1997 (1)
McIsaac et al., 2010 (6)
Weed and Kanwar, 1996 (4)
Cambardella et al., 2015 (7)
Cambardella et al., 2015 (7)
Randall et al., 1997 (1)
Randall et al., 1997 (1)
McIsaac et al., 2010 (6)
Thomas et al., 2014 (3)
McIsaac et al., 2010 (6)
Thomas et al., 2014 (3)
Masarik, et al., 2014 (2)
Cambardella et al., 2015 (7)
*16 -37X greater nitrate loss below continual corn cropping systems compared to perennial systems
Nitrate concentration below
root zone
Nitrate Leaching Potential
0
Economic Optimal Nitrogen Rates
Forest/
Alfalfa
Soybean Corn Potato
Prairie/
CornCRP
Soybean
Masarik, UW-Extension
Groundwater Susceptibility
The GCSM was developed by the DNR, the US
Geological Survey (USGS), the Wisconsin
Geological & Natural History Survey (WGNHS),
and the University of Wisconsin – Madison in
the mid-1980s.
Nitrate concentration below
root zone
Nitrate Leaching Potential
0
Economic Optimal Nitrogen Rates
Forest/
Alfalfa
Soybean Corn Potato
Prairie/
CornCRP
Soybean
Masarik, UW-Extension
Nitrate Concentration
Generalized Nitrate Leaching Potential
0
Economic Optimal Nitrogen Rates
Forest/
Prairie/
CRP
Alfalfa
Soybean
Corn Potato
CornSoybean
Masarik, UW-Extension
Poor
Good
UW Nitrogen Guidelines get us to a
baseline Level of nitrate concentration
in groundwater ~ Right Amount
Nitrate Concentration
Water Quality/
Nitrate
Concentration
0
Economic Optimal Nitrogen Rates
Forest/
Prairie/
CRP
Alfalfa
Soybean
Corn Potato
CornSoybean
Masarik, UW-Extension
Nitrate Concentration
GW NO3-N = f(Crop N Requirements, Excess N, Soils, Geology)
0
Economic Optimal Nitrogen Rates
Forest/
Prairie/
CRP
Alfalfa
Soybean
Corn Potato
CornSoybean
Masarik, UW-Extension
Improved Nitrogen Use Efficiency
through right form, right time and
right place techniques
Poor
Good
Nitrate Concentration
Water Quality/
Nitrate
Concentration
0
Economic Optimal Nitrogen Rates
Forest/
Prairie/
CRP
Alfalfa
Soybean
Corn Potato
CornSoybean
Masarik, UW-Extension
Septic systems and nitrate
Robertson and Harman 1999
• Designed to dispose of human waste in a manner that prevents
bacteriological contamination of groundwater supplies.
• Do not effectively remove all contaminants from wastewater:
Nitrate, chloride, viruses?, pharmaceuticals?, hormones?
Comparing Land-use Impacts
Corn1
(per acre)
Prairie1
(per acre)
Septic 2
System
Total Nitrogen Inputs (lb)
169
9
20-25
Nitrogen Leaching Loss (lb)
32
0.04
16-20
Amount N lost to leaching (%)
19
0.4
80-90
1 Data from Masarik, 2014
2 Data from Tri-State Water Quality Council, 2005 and EPA 625/R-00/008
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
20 lbs
20 acres
20 acres
Comparing Land-use Impacts
20 lbs/septic system x 1 septic systems = 20 lbs
1/32nd the impact on water quality
0.44 mg/L
Assuming 10 inches of recharge
32 lbs/ac x 20 acres = 640 lbs
14 mg/L
Water table
Stream
Water table
Stream
32 lbs/ac x 20 acres = 640 lbs
20 lbs/septic system
Comparing Land-use Impacts
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs
32 lbs/ac x 20 acres = 640 lbs
20 acres
20 acres
32 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs
20 lbs/septic system x 32 septic systems = 640 lbs
Using these numbers: 32 septic systems on 20 acres (0.6 acre lots) needed to achieve
same impact to water quality as 20 acres of corn
http://www.uwsp.edu/cnr-ap/watershed/Pages/wellwaterviewer.aspx
Average Nitrate-N concentration by section.
Source: WI Well Water Viewer
Category
Agriculture
Corn
Other Row
Forage
Ag-Total
Acres
1,399
8,611
7,895
2,187
20,092
Watershed
Area
%
2
11
10
3
27
Low
Estimate
Low N Loss
Med
Estimate
Med N Loss
High
Estimate
High N Loss
lbs N/acre
lbs N
lbs N/acre
lbs N
lbs N/acre
lbs N
22
36
50
0
30,781
309,987
394,767
0
735,535
36
75
138
10
50,369
645,806
1,089,557
21,873
1,807,604
50
100
200
20
69,957
861,074
1,579,068
43,747
2,553,845
50 – 60 homes/100 acres
~2 acre lot sizes
70-80 homes/275 acres
~ 4 acre lot sizes
Source
Septic System
Source
Fertilized
Lawns
Estimated
#
1,856
Low Rate
lbs/system
16
Total N Loss
lbs
29,696
High Rate
lbs/system
20
Total N Loss
lbs
37,120
Estimated
acres
Low Rate
lbs/acre
Total N Loss
lbs
High Rate
lbs/system
Total N Loss
lbs
464
5
2,320
13
6,032
Duck Creek Nitrogen Budget
Category
Agriculture
Corn
Other Row
Forage
Ag-Total
Source
Septic System
Source
Fertilized
Lawns
37120
5%
Acres
1,399
8,611
7,895
2,187
20,092
Watershed
Area
%
2
11
10
3
27
Low
Estimate
Low N Loss
Med
Estimate
Med N Loss
High
Estimate
High N Loss
lbs N/acre
lbs N
lbs N/acre
lbs N
lbs N/acre
lbs N
22
36
50
0
30,781
309,987
394,767
0
735,535
36
75
138
10
50,369
645,806
1,089,557
21,873
1,807,604
50
100
200
20
69,957
861,074
1,579,068
43,747
2,553,845
Estimated
#
1,856
Low Rate
lbs/system
16
Total N Loss
lbs
29,696
High Rate
lbs/system
20
Total N Loss
lbs
37,120
Estimated
acres
Low Rate
lbs/acre
Total N Loss
lbs
High Rate
lbs/system
Total N Loss
lbs
464
5
2,320
13
6,032
6032
1%
735535
94%
Lowest Agricultural Estimate
37120
2%
6032
0%
1807604
98%
Medium Agricultural Estimate
37120
2%
6032
0%
2553845
98%
Highest Agricultural Estimate
How to explain the variability
of nitrate across WI?

Coarse textured
surficial deposits

Shallow carbonate
rock aquifers

Watershed land use
portfolio
Siim Sepp
Bill Hafs
Coarse textured surficial deposits
Map created using: Groundwater Contamination Susceptibility Model (GCSM); Surficial Deposits ("sdppw95c")
The GCSM was developed by the DNR, the US Geological Survey (USGS), the Wisconsin Geological & Natural History Survey
(WGNHS), and the University of Wisconsin – Madison in the mid-1980s.
Shallow carbonate
rock aquifers
Photo credits: Ken Bradbury, WGNHS
Watershed land use portfolio
Low
High
Nitrate concentration in groundwater
Agricultural Lands of Wisconsin
Annual Row Crops
Forage Crops/
Pasture/
CRP
Maps produced using WISCLAND
Data Coverage. 2002. WiDNR/EDM
Agricultural Lands of Wisconsin
Row Cropping Systems
Forage Crops/Pasture/CRP
Maps produced using WISCLAND Data Coverage. 2002. WiDNR/EDM
What can be done to reduce nitrate levels?

Short term

Municipal Wells (GCC, 2015)

47 systems have spent >$32 million as of 2012




Water Treatment
New wells
Blending
Private Wells (Lewandowski et. al. 2008)
New well (not guaranteed, deeper adds to expense) - $7,200
 Bottled water - $190/person/year
 Water treatment devices $800 + 100/yr




Reverse osmosis
Distillation
Anion exchange
Long-term nitrogen reduction strategies
Practice
Timing
Nitrification Inhibitor
Cover Crops
Perennial
Extended Rotations
Details
% Nitrate-N
Reduction
Fall to Spring Pre-plant
6 (25)
Spring pre-plant/sidedress 40-60 split compared to fall
applied
5 (28)
Sidedress – Soil test based compared to pre-plant
7 (37)
Nitrapyrin – Fall – Compared to applied w/out nitrapyrin
9 (19)
Rye
31 (29)
Oat
28 (2)
Biofuel Crops (ex. switchgrass, miscanthus)
72 (23)
Conservation Reserve Program
85 (9)
At least 2 years of alfalfa or other perennial crops in a 4
or 5 year rotation
42 (12)
Iowa Nutrient Reduction Strategy, 2014
Improve delivery and efficiency of nitrogen
Conclusions
• (+) Some success in bringing down excessively
high concentrations
• (-) Nitrate loss to groundwater inevitable even under
current best management practices.
• (+) In areas where land use is consistent expect
groundwater nitrate concentrations to stabilize
• (-/+) Where land use changes - expect
concentrations to either increase or decrease
depending on change
Kevin Masarik, Center for Watershed Science and Education
kmasarik@uwsp.edu
http://www.uwsp.edu/cnr-ap/watershed
Long-term Nitrate Leaching Study of
Corn Agroecosystems and a Prairie
UW-Madison Arlington Research Farm
Optimal
(1996-2003)
No Fertilizer
Optimal
Goose Pond Sanctuary:
26 year old restored prairie
Brye et al., 2001, Brye et al., 2000, Brye et al., 2003, Masarik et al., 2014
Annual Nitrate
Leaching losses
Eight-year summary at Arlington, WI
Chiselplow
No-tillage
Prairie
Total precipitation (cm)
618
618
618
Total drainage (cm)
319
227
98
Precipitation lost to drainage (%)
52
37
16
Total NO3--N leaching loss (kg ha-1)
303
277
0.43
Amount N lost to leaching (%)
18
19
0.5
Flow weighted mean NO3-N Conc.
(mg L-1)
9.5
12.2
0.04
Equates to approximately 32 lbs per acre per year on average
that leaches past the root zone of corn agroecosystems