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Hey and Associates, Inc.
Use of Enhanced Ditch Plugs and
Riparian Wetlands to Reduce Nitrogen
and Phosphorus Export from S...
Hey and Associates, Inc.
Partners
UWM- Conservation and Environmental Studies
Hey and Associates, Inc.
“A Lake is A Reflection of its Watershed”
Source: Primary Components of a Watershed
(Heathcote, 1...
Hey and Associates, Inc.
“A Lake is A Reflection of its Watershed 
and Characteristics of its Floodplains and 
Riparian We...
Hey and Associates, Inc.
Water Quality Benefits of Floodplains
• Copper, J. R,  J. W. Gilliam, R. 
B. Daniels, and W. P. R...
Hey and Associates, Inc.
Water Quality Benefits of Floodplains
• Cooper et al (1987) 
monitored two small 
watersheds to d...
Hey and Associates, Inc.
Water Quality Benefits of Floodplains
• Wetland Treatment for Water Quality
Wetland
Type
Suspende...
Hey and Associates, Inc.
Water Quality Benefits of Floodplains
Conservation and Environmental StudiesUWM- Conservation and...
Hey and Associates, Inc.
Water Quality Benefits of Floodplains
Conservation and Environmental StudiesUWM- Conservation and...
Hey and Associates, Inc.
Water Quality Benefits of Floodplains
• As we have developed 
the landscape into 
agriculture and...
Hey and Associates, Inc.
Water Quality Benefits of Floodplains
• In many watersheds 
most small storms 
do not even over t...
Hey and Associates, Inc.
Typical Stream Floodplain
Source: NRCS
1.7 to 2.0 year Storm
2 to 10 year Storm
Conservation and ...
Hey and Associates, Inc.
Fox Lake, Wisconsin
• Fox Lake Inland Lake 
Protection and 
Rehabilitation District
• Wisconsin D...
Hey and Associates, Inc.
Fox Lake, Wisconsin
Surface area = 2,525 ac Conservation and Environmental StudiesUWM- Conservati...
Hey and Associates, Inc.
Fox Lake, Wisconsin
• In the 1950’s mean total 
phosphorus levels in 
Fox Lake were less than 
50...
Hey and Associates, Inc.
Fox Lake, Wisconsin
90% of Drainage Area
is in agricultural
Conservation and Environmental Studie...
Hey and Associates, Inc.
Elements of the Fox Lake Restoration Plan
1. Shoreline 
Stabilization 
2. Watershed Protection
3....
Hey and Associates, Inc.
Fox Lake Watersheds
Total Watershed = 35,574 ac
Watershed to Lake Ratio 14:1
3,894 ac
13,693 ac
1...
Hey and Associates, Inc.
Sediment and Phosphorus Inputs to 
Fox Lake
Sub-watershed
Land Area
(ac)
Sediment
Load
(tons/yr)
...
Hey and Associates, Inc.
Strategy to Reduce Sediment and 
Phosphorus Inputs to Fox Lake
• Conservation practices on 
agric...
Hey and Associates, Inc.
Alto Creek Wetland Project
Purpose: To reduce 
sediment and nutrient 
loadings to Fox Lake 
durin...
Hey and Associates, Inc.
Alto Creek Wetland Project
Date
TSS 
(mg/l)
TP 
(mg/l)
SRP 
(mg/l)
TKN 
(mg/l)
NO2/ NO3 
(mg/l)
5...
Hey and Associates, Inc.
Alto Creek Wetland Project
Design Criteria:
• Reasonable access
• Low maintenance
• Low cost
• Po...
Hey and Associates, Inc.
Alto Creek Wetland Project
• The process was 
started with detailed  
mapping of the 
watershed. ...
Hey and Associates, Inc.
Alto Creek Wetland Project
• A 1‐foot contour map 
was created from a 
aerial fly over. 
Conserva...
Hey and Associates, Inc.
Alto Creek Wetland Project
• Selection of potential 
restoration sites based 
on topography and 
...
Hey and Associates, Inc.
Mapping of Soils and Land Use in GIS
Conservation and Environmental StudiesUWM- Conservation and ...
Hey and Associates, Inc.
Alto Creek Land Use and Soils
Land use Soil group Area(acres)
Water B 32.1
Water D 139
Commercial...
Hey and Associates, Inc.
Runoff Curve Numbers
Water B 98
Water D 98
Commercial B 96
Agriculture A 67
Agriculture B 76
Agri...
Hey and Associates, Inc.
Alto Creek Wetland Project
• Developed a 
hydrology model using 
HEC‐HMS. 
Conservation and Envir...
Hey and Associates, Inc.
Alto Creek Wetland Project
Water Level Control Structure
HEC-RAS
Cross-sections
• Developed a 
hy...
Hey and Associates, Inc.
Alto Creek Wetland Project
• Selection of design storms. 
~ 5 year 24-hr Storm Conservation and E...
Hey and Associates, Inc.
Alto Creek Wetland Project
• Ecological assessment of each potential site. 
Conservation and Envi...
Hey and Associates, Inc.
Alto Creek Wetland Project
Reed Carney Grass
Cattails
Conservation and Environmental StudiesUWM- ...
Hey and Associates, Inc.
Alto Creek Wetland Project
CTH F
Conservation and Environmental StudiesUWM- Conservation and Envi...
Hey and Associates, Inc.
Water Resources, Wetlands and EcologyWater Resources, Wetlands and Ecology
Conservation and Envir...
Hey and Associates, Inc.
Alto Creek Wetland Project
Conservation and Environmental StudiesUWM- Conservation and Environmen...
Hey and Associates, Inc.
Alto Creek Wetland Project
Drawdown 
notch and fish 
passageway
Conservation and Environmental St...
Hey and Associates, Inc.
Alto Creek Wetland Project
Conservation and Environmental StudiesUWM- Conservation and Environmen...
Hey and Associates, Inc.
Alto Creek Wetland Project
Conservation and Environmental StudiesUWM- Conservation and Environmen...
Hey and Associates, Inc.
Alto Creek Wetland Project
Conservation and Environmental StudiesUWM- Conservation and Environmen...
Hey and Associates, Inc.
Alto Creek Wetland Project
Conservation and Environmental StudiesUWM- Conservation and Environmen...
Hey and Associates, Inc.
Alto Creek Wetland Project
Conservation and Environmental StudiesUWM- Conservation and Environmen...
Hey and Associates, Inc.
Alto Creek Wetland Project
Conservation and Environmental StudiesUWM- Conservation and Environmen...
Hey and Associates, Inc.
Alto Creek Wetland Project
Conservation and Environmental StudiesUWM- Conservation and Environmen...
Hey and Associates, Inc.
Alto Creek Wetland Project
Conservation and Environmental StudiesUWM- Conservation and Environmen...
Hey and Associates, Inc.
Stream Flow 
Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
Hey and Associates, Inc.
Area of Groundwater Discharge
Weir Structure 
(AC‐1)
Upstream Sample Site 
(AC‐2)
Groundwater 
Di...
Hey and Associates, Inc.Conservation and Environmental Studies
Groundwater 
Discharge Area
UWM- Conservation and Environme...
Hey and Associates, Inc.
Total Suspended Solids (TSS) 
Conservation and Environmental StudiesUWM- Conservation and Environ...
Hey and Associates, Inc.
Total Suspended Solids (TSS) 
61.1%
Conservation and Environmental StudiesUWM- Conservation and E...
Hey and Associates, Inc.
Total Kjeldahl Nitrogen (TKN) 
76.8%
Conservation and Environmental StudiesUWM- Conservation and ...
Hey and Associates, Inc.
NO2/NO3
35.9%
Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
Hey and Associates, Inc.
Total Phosphorus 
61.1%
Conservation and Environmental StudiesUWM- Conservation and Environmental...
Hey and Associates, Inc.
Dissolved Phosphorus 
65.5%
67% of the total phosphorus is in the form of
soluble reactive phosph...
Hey and Associates, Inc.
Total Phosphorus 
Conservation and Environmental StudiesUWM- Conservation and Environmental Studi...
Hey and Associates, Inc.
Dissolved Phosphorus 
Conservation and Environmental StudiesUWM- Conservation and Environmental S...
Hey and Associates, Inc.
Total Kjeldahl Nitrogen (TKN) 
Conservation and Environmental StudiesUWM- Conservation and Enviro...
Hey and Associates, Inc.
Nitrite/Nitrate 
Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
Hey and Associates, Inc.
Alto Creek Wetland Project
• Conclusions:
– Use of low‐head dams 
can be used to enhance 
the con...
Hey and Associates, Inc.
Alto Creek Wetland Project
• Conclusions:
– Because Alto Creek 
carry's little suspended 
sedimen...
Hey and Associates, Inc.
Questions
Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
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Use of enhanced ditch plugs

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69th SWCS International Annual Conference
July 27-30, 2014
Lombard, IL

Published in: Environment
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Use of enhanced ditch plugs

  1. 1. Hey and Associates, Inc. Use of Enhanced Ditch Plugs and Riparian Wetlands to Reduce Nitrogen and Phosphorus Export from Small Agricultural Watersheds Neal O’Reilly, Ph.D., PH Conservation and Environmental Studies University of Wisconsin - Milwaukee
  2. 2. Hey and Associates, Inc. Partners UWM- Conservation and Environmental Studies
  3. 3. Hey and Associates, Inc. “A Lake is A Reflection of its Watershed” Source: Primary Components of a Watershed (Heathcote, 1998). Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  4. 4. Hey and Associates, Inc. “A Lake is A Reflection of its Watershed  and Characteristics of its Floodplains and  Riparian Wetlands” O’Reilly’s Corollary Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  5. 5. Hey and Associates, Inc. Water Quality Benefits of Floodplains • Copper, J. R,  J. W. Gilliam, R.  B. Daniels, and W. P. Robarge.  (1987). Riparian areas as  filters for agricultural  sediment. Soil Science Society  of America Journal. 51:416‐ 420.  • Copper, J. R. and J. W.  Gilliam. (1987). Phosphorus  redistribution from cultivated  fields into riparian areas. Soil  Science Society of America  Journal. 51:1600‐1604. Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  6. 6. Hey and Associates, Inc. Water Quality Benefits of Floodplains • Cooper et al (1987)  monitored two small  watersheds to determine the  sediment and nutrient  removal efficiencies of  stream buffers.   • Copper found that stream  buffers can reduce sediment  delivery from cultivated  fields between 84% and 90% and phosphorus by 50% (Copper et al, 1987, and  Copper and Gilliam, 1987).  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  7. 7. Hey and Associates, Inc. Water Quality Benefits of Floodplains • Wetland Treatment for Water Quality Wetland Type Suspended Solids Total Phosphorus NH3 Lead Zinc Constructed 80 58 44 83 42 Natural 76 5 25 69 62 Source: (Strecker et. al. 1992) Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  8. 8. Hey and Associates, Inc. Water Quality Benefits of Floodplains Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  9. 9. Hey and Associates, Inc. Water Quality Benefits of Floodplains Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  10. 10. Hey and Associates, Inc. Water Quality Benefits of Floodplains • As we have developed  the landscape into  agriculture and urban  areas we have not only  modified the land use  but also the drainage  system and floodplains  through ditching and  tiling.  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  11. 11. Hey and Associates, Inc. Water Quality Benefits of Floodplains • In many watersheds  most small storms  do not even over top  the banks of the  stream and have  limited contact with  riparian vegetation.   Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  12. 12. Hey and Associates, Inc. Typical Stream Floodplain Source: NRCS 1.7 to 2.0 year Storm 2 to 10 year Storm Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  13. 13. Hey and Associates, Inc. Fox Lake, Wisconsin • Fox Lake Inland Lake  Protection and  Rehabilitation District • Wisconsin Department  of Natural Resources Fox Lake Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  14. 14. Hey and Associates, Inc. Fox Lake, Wisconsin Surface area = 2,525 ac Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  15. 15. Hey and Associates, Inc. Fox Lake, Wisconsin • In the 1950’s mean total  phosphorus levels in  Fox Lake were less than  50 ug/l.   • Today total phosphorus  ranges from 150 to 400  ug/l Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  16. 16. Hey and Associates, Inc. Fox Lake, Wisconsin 90% of Drainage Area is in agricultural Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  17. 17. Hey and Associates, Inc. Elements of the Fox Lake Restoration Plan 1. Shoreline  Stabilization  2. Watershed Protection 3. Aquatic Plant  Management 4. Fishery Management 5. Dam Replacement 6. Public Education Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  18. 18. Hey and Associates, Inc. Fox Lake Watersheds Total Watershed = 35,574 ac Watershed to Lake Ratio 14:1 3,894 ac 13,693 ac 14,900 ac Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  19. 19. Hey and Associates, Inc. Sediment and Phosphorus Inputs to  Fox Lake Sub-watershed Land Area (ac) Sediment Load (tons/yr) Phosphorus Load (lbs/yr) % total Phosphorus Load % of Total Load Due to Cropland Alto Creek 13,693 6,477 23,859 45% 98 Cambra Creek 14,900 4,156 18,530 35% 96 Drew Creek 3,894 1,861 6,834 13% 96 Fox Lake 3,087 1,000 3,845 7% 97 Total 35,573 13,494 53,068 100% Sub-watershed Land Area (ac) Sediment Load (tons/yr) Phosphorus Load (lbs/yr) % total Phosphorus Load % of Total Load Due to Cropland Alto Creek 13,693 6,477 23,859 45% 98 Cambra Creek 14,900 4,156 18,530 35% 96 Drew Creek 3,894 1,861 6,834 13% 96 Fox Lake 3,087 1,000 3,845 7% 97 Total 35,573 13,494 53,068 100% Conservation and Environmental StudiesUWM- Conservation and Environmental Studies Based on WinHUSLE Modeling
  20. 20. Hey and Associates, Inc. Strategy to Reduce Sediment and  Phosphorus Inputs to Fox Lake • Conservation practices on  agricultural fields and  barnyard management  systems • Buffers and grass waterways  on tributary drainage  channels • Improved water filtering  through riparian wetlands  on main channels Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  21. 21. Hey and Associates, Inc. Alto Creek Wetland Project Purpose: To reduce  sediment and nutrient  loadings to Fox Lake  during moderate storms. Approach: Series of low‐ head control structures  to cause moderate storm  events to spill over into  existing riparian  wetlands to filter  nutrients. Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  22. 22. Hey and Associates, Inc. Alto Creek Wetland Project Date TSS  (mg/l) TP  (mg/l) SRP  (mg/l) TKN  (mg/l) NO2/ NO3  (mg/l) 5/18/2006 19 0.192 0.131 1.45 7.47 5/25/2006 66 0.061 0.035 0.92 8.42 5/31/2006 34 0.157 0.083 1.58 5.96 6/13/2006 20 0.084 0.042 0.54 10.8 6/19/2006 19 0.092 0.045 0.71 11.5 12/8/2009 10 0.050 0.022 0.4 11.2 5/5/2010 12 0.078 0.051 0.91 7.88 8/2/2010 20 0.237 0.217 1.16 7.29 8/22/2010 14 0.149 0.107 0.62 9.56 Mean 23.78 0.122 0.081 0.92 8.90 St. Dev.  17.27 0.06 0.06 0.41 1.96 Conservation and Environmental Studies SRP = 66% of Total P UWM- Conservation and Environmental Studies
  23. 23. Hey and Associates, Inc. Alto Creek Wetland Project Design Criteria: • Reasonable access • Low maintenance • Low cost • Potentially constructable by untrained labor, such as  “Secured Work Force” • Does not impact on regulatory flood elevations • Does not cause prolonged flooding of adjacent crops • Allows fish passage • Requires minimal wetland disturbance Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  24. 24. Hey and Associates, Inc. Alto Creek Wetland Project • The process was  started with detailed   mapping of the  watershed.  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  25. 25. Hey and Associates, Inc. Alto Creek Wetland Project • A 1‐foot contour map  was created from a  aerial fly over.  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  26. 26. Hey and Associates, Inc. Alto Creek Wetland Project • Selection of potential  restoration sites based  on topography and  potential for  maximizing the spread  of storm water into  the floodplain  wetlands.   Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  27. 27. Hey and Associates, Inc. Mapping of Soils and Land Use in GIS Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  28. 28. Hey and Associates, Inc. Alto Creek Land Use and Soils Land use Soil group Area(acres) Water B 32.1 Water D 139 Commercial B 1.7 Agriculture A 9.6 Agriculture B 4322.5 Agriculture C 8.1 Agriculture D 890.6 HD‐Residential B 110.1 HD‐Residential D 14.8 LD‐Residential B 173.3 LD‐Residential D 37.5 Grass/Pasture B 1056.9 Grass/Pasture D 58 Forest B 52.1 Forest D 17 Total Area 6923.3 Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  29. 29. Hey and Associates, Inc. Runoff Curve Numbers Water B 98 Water D 98 Commercial B 96 Agriculture A 67 Agriculture B 76 Agriculture C 83 Agriculture D 86 HD‐Residential B 87 HD‐Residential D 93 LD‐Residential A 54 LD‐Residential B 70 LD‐Residential D 85 Grass/Pasture B 68 Grass/Pasture C 78 Grass/Pasture D 83 Forest B 61 Forest D 80 Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  30. 30. Hey and Associates, Inc. Alto Creek Wetland Project • Developed a  hydrology model using  HEC‐HMS.  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  31. 31. Hey and Associates, Inc. Alto Creek Wetland Project Water Level Control Structure HEC-RAS Cross-sections • Developed a  hydraulics model  using HEC‐RAS to  understand the  potential areas of  inundation and impact  on regulatory  floodplains.  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  32. 32. Hey and Associates, Inc. Alto Creek Wetland Project • Selection of design storms.  ~ 5 year 24-hr Storm Conservation and Environmental StudiesUWM- Conservation and Environmental Studies Accumulative. Total P Load (%) 
  33. 33. Hey and Associates, Inc. Alto Creek Wetland Project • Ecological assessment of each potential site.  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  34. 34. Hey and Associates, Inc. Alto Creek Wetland Project Reed Carney Grass Cattails Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  35. 35. Hey and Associates, Inc. Alto Creek Wetland Project CTH F Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  36. 36. Hey and Associates, Inc. Water Resources, Wetlands and EcologyWater Resources, Wetlands and Ecology Conservation and Environmental Studies Plan View Cross-Section UWM- Conservation and Environmental Studies
  37. 37. Hey and Associates, Inc. Alto Creek Wetland Project Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  38. 38. Hey and Associates, Inc. Alto Creek Wetland Project Drawdown  notch and fish  passageway Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  39. 39. Hey and Associates, Inc. Alto Creek Wetland Project Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  40. 40. Hey and Associates, Inc. Alto Creek Wetland Project Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  41. 41. Hey and Associates, Inc. Alto Creek Wetland Project Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  42. 42. Hey and Associates, Inc. Alto Creek Wetland Project Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  43. 43. Hey and Associates, Inc. Alto Creek Wetland Project Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  44. 44. Hey and Associates, Inc. Alto Creek Wetland Project Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  45. 45. Hey and Associates, Inc. Alto Creek Wetland Project Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  46. 46. Hey and Associates, Inc. Alto Creek Wetland Project Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  47. 47. Hey and Associates, Inc. Stream Flow  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  48. 48. Hey and Associates, Inc. Area of Groundwater Discharge Weir Structure  (AC‐1) Upstream Sample Site  (AC‐2) Groundwater  Discharge Area Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  49. 49. Hey and Associates, Inc.Conservation and Environmental Studies Groundwater  Discharge Area UWM- Conservation and Environmental Studies
  50. 50. Hey and Associates, Inc. Total Suspended Solids (TSS)  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  51. 51. Hey and Associates, Inc. Total Suspended Solids (TSS)  61.1% Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  52. 52. Hey and Associates, Inc. Total Kjeldahl Nitrogen (TKN)  76.8% Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  53. 53. Hey and Associates, Inc. NO2/NO3 35.9% Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  54. 54. Hey and Associates, Inc. Total Phosphorus  61.1% Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  55. 55. Hey and Associates, Inc. Dissolved Phosphorus  65.5% 67% of the total phosphorus is in the form of soluble reactive phosphorus
  56. 56. Hey and Associates, Inc. Total Phosphorus  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  57. 57. Hey and Associates, Inc. Dissolved Phosphorus  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  58. 58. Hey and Associates, Inc. Total Kjeldahl Nitrogen (TKN)  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  59. 59. Hey and Associates, Inc. Nitrite/Nitrate  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  60. 60. Hey and Associates, Inc. Alto Creek Wetland Project • Conclusions: – Use of low‐head dams  can be used to enhance  the connectivity of  stream flow with  riparian floodplain  wetlands. – Increasing this  connectivity can improve  the trapping of sediment  and nutrients.  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  61. 61. Hey and Associates, Inc. Alto Creek Wetland Project • Conclusions: – Because Alto Creek  carry's little suspended  sediment and most of  the Total Phosphorus is  in the dissolved form,  I  believe here biological  uptake is a more  important factor for  nutrient removal than  sedimentation.  Conservation and Environmental StudiesUWM- Conservation and Environmental Studies
  62. 62. Hey and Associates, Inc. Questions Conservation and Environmental StudiesUWM- Conservation and Environmental Studies

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