Water quality improvement by converting
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Transcript of Water quality improvement by converting
Water quality improvementby converting from
surface to sprinkler irrigation.
Dave Bjorneberg, Jim Ippolito, Anita KoehnARS Kimberly, ID
Upper Snake Rock WatershedAugust 2009
Upper Snake Rock Watershed – Idaho
1. 82,000 ha with 70,000 ha cropland (85%).
2. 270 mm annual precipitation, 90 mm May to Sept.
3. Daily rainfall >20 mm only six times during 2005-2008, five times in 2005.
4. About 40% sprinkler irrigated.
5. Monitoring for the Conservation Effects Assessment Project (CEAP) began in 2005.
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200
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1400
2005 2006 2007 2008 Average
Irrigation Rock Creek Precipitation
USR Water Input (mm)
1982
2006
• 24 return flow monitoring sites.• 5 sub-watersheds, 150 to 600 ha, 5 to 50% sprinkler irrigation
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500
1000
1971 2005 2006 2007 2008
Susp
ende
d Se
dim
ent (
kg/h
a)
InflowOutflowNet
Sediment loss has decreased since 1971 when watershed was 95% furrow irrigated.
USR Watershed
R2 = 0.08
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10000
0% 10% 20% 30% 40% 50% 60% 70% 80%
Sprinkler Irrigated Area (%)
Sedi
men
t Loa
d (lb
/a)
R2 = 0.88
R2 = 0.64
R2 = 0.07
R2 = 0.07
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4000
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0% 10% 20% 30% 40% 50% 60%
Furrow Irrigated Row Crop (%)
Sedi
men
t Loa
d (lb
/a)
PC1 (10%)PC2 (50%)TF1 (30%)TF3 (65%)EC (15%)
R2 = 0.49R2 = 0.32
R2 = 0.64
R2 = 0.52
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0.6
0.8
1.0
1.2
0% 10% 20% 30% 40% 50% 60%
Furrow Irrigated Row Crop (%)
Dis
solv
ed P
hosp
horu
s Lo
ad (l
b/a)
PC1 (10%)PC2 (50%)TF1 (30%)TF3 (65%)EC (15%)
outlet
Sprinkler
F out
F in
Furrow
Added two sites in 2012 within the PC1 sub-watershed (250 ha)
0100200300400500600700800900
1000
2005 2006 2007 2008 2010 2012 2013
Susp
ende
d Se
dim
ent (
kg/h
a)PC1 sub-watershed (July)
25%decrease
85%decrease
0.00
0.20
0.40
0.60
0.80
1.00
2005 2006 2007 2008 2010 2012 2013
Tota
l Pho
spho
rus
(kg/
ha)
PC1 sub-watershed (July)
0.00
0.02
0.04
0.06
0.08
0.10
2005 2006 2007 2008 2010 2012 2013
Dis
solv
ed P
hosp
horu
s (k
g/ha
)PC1 sub-watershed (July)
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50000
100000
150000
200000
250000
July Aug. July Aug.
F inF outPC1
Suspended Sediment Loads in PC1 (kg)
2012 2013
90% reduction in F out from 2012 to 2013.
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100
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300
400
July Aug. July Aug.
F inF outPC1
Total Phosphorus Loads in PC1 (kg)
2012 2013
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4000
6000
8000
2012 2013 2014
F inF outPC1
June-July Average Sediment Concentrations (mg/L)
outlet
Sprinkler
F out
F in
Furrow
Summary• Sediment loss from the USR has dramatically decreased
since 1970 due to multiple practices.
• No correlation between amount of sprinkler irrigation and sediment loss among sub-watersheds.
• Sediment and P loss from a farm decreased 90% when the entire farm was converted to sprinkler irrigation.
• Furrow irrigation management or conversion to sprinkler irrigation is the key to reducing sediment and phosphorus losses.
Questions?