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Phosphorus Fate and Transport in an Impounded River System. Implications for TMDL Stakeholders and Extension Educators. Dean Baas MSU Geological Sciences Department MSU Extension Land & Water Program W. K. Kellogg Biological Station. Presentation Outline.
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Phosphorus Fate and Transport in an Impounded River System Implications for TMDL Stakeholders and Extension Educators Dean Baas MSU Geological Sciences Department MSU Extension Land & Water Program W. K. Kellogg Biological Station
Presentation Outline • Lake Allegan/Kalamazoo River phosphorus TMDL • Overview • Research • Lake Allegan phosphorus • Sources • Point • Nonpoint • Kalamazoo River watershed phosphorus sources, fate and transport • Agriculture • Urban • Impoundments • Implications for TMDL stakeholders and extension educators • Preliminary Conclusions • Questions and Discussion
Lake Allegan/Kalamazoo River phosphorus TMDL watershed • 1600 mi2 watershed in Southwest Michigan • Agricultural watershed • Nationally recognized stakeholder drivenphosphorus TMDL Grand Rapids Battle Creek Kalamazoo Portage
Lake Allegan • EPA 303d list as phosphorus impaired waterbody • 2.5 mi2 impoundment hydroelectric dam impoundment • Periodic nuisance algal blooms • Carp/Catfish
Lake Allegan Water Quality • Reductions allocated as follows: • Point source dischargers – 23% • All other sources of phosphorus (NPS) - 50%
Total Maximum Daily Load “The primary purpose of the TMDL program is to protect public health and the health of impaired aquatic ecosystems by ensuring attainment of water quality standards, including beneficial uses.” US EPA, 1998
TMDL Research Education and Extension • Michigan State University Extension Land & Water Program at KBS received: • In 2001, a $249,000 319 grant to develop a nonpoint source tracking system, and help develop, coordinate & track implementation activities.
TMDL Research Education and Extension • Michigan State University Extension Land & Water Program at KBS received: • In 2001, a $249,000 319 grant to develop a nonpoint source tracking system, and help develop, coordinate & track implementation activities. • In 2003, a $485,000 USDA-CSREES Integrated Water Program grant to: • Characterize the sources, fate and transport of phosphorus in the TMDL watershed. • Integrate research, education, and extension to enhance phosphorus reduction strategies through the stakeholder driven TMDL organization.
Research 17 16 15 3 2 8 13 14 6 4 10 5 9 7 11 12 1
Research - Sampling • Auto-samplers (1 parameter) • Daily composite TP • Weekly grab samples (17 parameters) • TP, TDP, Ca2+, Mg2+, Na+, K+, Cl-, NO3-, SO42-, alkalinity, temperature, pH, specific conductance, DO, %DO, chlorophyll A • Four synoptic samplings (40 parameters) • Weekly + Sc, Ti, V, Zn, Cr, Co, Cu, As, Se, Rb, Mo, Sn, Pb, Mn, Fe Sr, Ba, U, Al, B, Ni, Cd, Ag • Discharge • USGS gaging stations • Isco autosampler stage
Phosphorus Sources – Lake Allegan • 1998 MDEQ Load Estimate: 145,200 lbs/g.s. • 2005 Load Estimate: 98,400 lbs/g.s (32 % reduction) • 2006 Load Estimate: 120,800 lbs/g.s. (17% reduction)
46 – 88 lbs/mi2 28 – 51 lbs/mi2 43 – 69 lbs/mi2 17 – 37 lbs/mi2 Phosphorus Sources Growing Season NPS TP Exports • Excludes urban areas • Mixed landuse watersheds In General NPS Export Coefficients Increase
Phosphorus SourcesNPS Agricultural Phosphorus Fractions DP:TP = 25 % PP:TP = 75 % DP:TP = 70 % PP:TP = 30 % DP:TP = 40 % PP:TP = 60 %
Phosphorus Sources Agricultural TMDL Implications DP:TP = 25 % PP:TP = 75 % DP:TP = 70 % PP:TP = 30 % • Agricultural watersheds • Conventional approach is to reduce P by promoting soil conservation BMPs • High dissolved P watersheds • Less effective • Need to reduce P inputs • High particulate P watersheds • More effective DP:TP = 40 % PP:TP = 60 %
Phosphorus SourcesGrowing Season Urban NPS TP Exports • Urban areas • Kalamazoo/Portage • Battle Creek 170 - 370 lbs/mi2 230 – 430 lbs/mi2
Phosphorus SourcesUrban NPS TP Exports • Kalamazoo urban event
Phosphorus SourcesUrban TMDL Implications • Urban watersheds • Event sampling required to capture source • Continue storm water management efforts 170 - 370 lbs/mi2 230 – 430 lbs/mi2
Phosphorus Sources, Transport and FateImpoundments • Three Impoundments • Emmett Street Dam • Morrow Lake • Lake Allegan • Influence sources, transport and fate of phosphorus
Phosphorus Sources, Transport and FateImpoundments • Emmett Street impoundment sinking phosphorus • 2005: 1700 lbs • 2006: 2600 lbs • Reducing the export of phosphorus
Phosphorus Sources, Transport and FateImpoundments • Emmett Street impoundment • Fed by the Battle Creek River • High ratio of dissolved to total phosphorus • Impoundment sinking DP • Suggest DP precipitation • Geochemical process
Phosphorus Sources, Transport and FateImpoundments • Morrow Lake Impoundment sourcing phosphorus • 2005: 19,000 lbs • 2006: 9,500 lbs • Increasing the export of phosphorus
Phosphorus Sources, Transport and FateImpoundments • Morrow Lake • 1.7 mi2 impoundment • Located approximately 2/3 down the watershed • Mediates phosphorus transport
Phosphorus Sources, Transport and FateImpoundments • Outlet growing season mean TP concentration relatively constant • Varying inlet concentrations
flow Phosphorus Sources, Transport and FateImpoundments • During the growing season, Morrow Lake inlet to outlet: • Particulate phosphorus increases • Dissolved phosphorus decreases • Dissolved nitrate decreases
flow Phosphorus Sources, Transport and FateImpoundments • 2006 Chlorophyll A sampled • Chlorophyll A increases with particulate phosphorus • Algal activity • Biological process
The Morrow Impoundment: Decouples the upstream portion of the watershed Replaces phosphorus reduced in that region Forces the downstream portion of the watershed to produce reductions to meet Lake Allegan TMDL goals Phosphorus Sources, Transport and FateImpoundments P reduction towards goal No net P reduction P reduced P replaced
Phosphorus Sources, Transport and FateImpoundments • Lake Allegan impoundment sinking phosphorus • 2005: 15,000 lbs • 2006: 28,000 lbs • Storing phosphorus which slows the recovery
Implications for TMDL Stakeholders and Extension Educators • Sources of total phosphorus are not sufficient for reduction strategies • Phosphorus fractions • BMP selection • Phosphorus source and fraction changes could have unexpected impact • Phosphorus processes are important • Biological • Geochemical • Can help, hurt, or mediate • Outputs may change with input changes • Impoundments • Environment for processes • Time for processes • Impact timeframe for improvement
Preliminary Conclusions • Detailed phosphorus and chemistry data is required to develop TMDL phosphorus reduction strategies • Phosphorus analysis should include phosphorus forms • BMP recommendations should be based on phosphorus forms • Impoundments should be evaluated to determine their impact on the transport and fate of phosphorus • Target reduction must consider the long term impact of phosphorus processes