TMDL study and water quality assessment for a suburban stream

About this project

Minnesota Pollution Control Agency
completion date

Barr completed a total maximum daily load (TMDL) study of Nine Mile Creek in the southwest suburban area of Minneapolis. The study was conducted in cooperation with the Minnesota Pollution Control Agency (MPCA) for the Nine Mile Creek Watershed District. The creek was listed on the MPCA’s impaired-waters inventory for turbidity levels exceeding the Class 2B water quality standard of 25 NTUs (nephelometric units—turbidity is measured as the amount of light scattered in a water sample and reported as NTUs). The creek is also listed for chloride and fish index of biotic integrity (IBI). In response to these impairment listings, the watershed district authorized comprehensive stream and watershed assessments that include extensive field data collection followed by computer simulation and mass-balance modeling of streamwater-quality conditions to assess the management practices that must be implemented to restore the creek to compliance with MPCA standards.

The first phase of work involved characterization of stream hydrology and water-quality conditions, including chemical and biological water quality. Barr surveyed the physical characteristics of the stream according to the Rosgen stream classification system and installed three continuous-flow-gaging and automatic-sampling stations on the main stem and branches of the creek. We’re conducting year-round continuous discharge monitoring and episodic water-quality sampling—both baseflow and stage-activated storm event—for a wide variety of water-quality constituents. We’re also concurrently studying stream habitat and the benthic macroinvertebrate and fish communities of the creek to determine any possible biotic impairments related to urban stormwater runoff and road salt applications. Following MPCA protocols for fish-community sampling and physical habitat assessment for wadeable streams, Barr completed fishery surveys for the development of the Index of Biotic Integrity (IBI) scores throughout the watershed. The Nine Mile Creek Watershed District, MPCA and Barr completed a total TMDL analysis of Nine Mile Creek and its watershed to address the fish IBI listing on the MPCA’s Section 303(d) Impaired Waters list. Barr collected continuous turbidity data to show that the creek should be de-listed for turbidity. Working with data collected by our staff and the Metropolitan Council, Barr has prepared the watershed and stream characterization, stressor identification, and causal analysis/diagnosis for the biological impairments.

A detailed computer model (i.e., XP-SWMM) has been developed to simulate stream hydrology and its effect on aquatic habitat. Calibrated to observed conditions, this model can be operated in “what if” mode to evaluate the benefits of implementing various watershed best management practices (BMPs) designed to reduce the rates and volumes of watershed runoff. Stakeholder meetings were organized and conducted to inform interested parties about TMDL study progress and to gather public input about proposed BMPs. In addition, mass-balance modeling and a TMDL report for chloride was developed/approved and implementation planning was completed.

Key team members

Greg Wilson

Senior Water Resources Engineer

Chris Bonick

Senior Water Resources Scientist

Bob Obermeyer

Vice President
Senior Water Resources Engineer

Mike Strong

Senior GIS Specialist

Meg Rattei

Senior Biologist

Related water projects

Landfill-gas monitoring at remediated dump to support brownfield redevelopment
Spillway upgrades at St. Cloud Dam
Landscape master plan for watershed district
Park and landscape design for Mouse River enhanced flood protection project
O&M manual for green-infrastructure stormwater BMPs
Design of abutment wall extension at Dells hydro station
Design and prioritization of spillway gate repairs
Coffee Creek trout stream restoration
spillway replacement at Odland Dam
Detailed assessment of phosphorus sources and loading to Minnesota watersheds
Dry-stack tailings management
Tailings basin expansion and closure options
Groundwater monitoring for Fridley Filtration Plant rehabilitation
Incident energy and arc flash hazard analyses of three facilities
Natural-resources management plan for suburban park
Investigation and remediation of jet-fuel release
Routine electrical, controls, and instrumentation support
Feasibility design and inspections of an urban stormwater-management tunnel
Vapor intrusion investigation and mitigation in a residential neighborhood
Snowpack monitoring and lake drawdown for Minnesota watershed district
Preliminary engineering for Mouse River enhanced flood protection project
Groundwater modeling for 1,4-dioxane
First-of-its-kind spent-lime stormwater BMP treatment system
Environmental impact assessment for mountain-bike trail
Albert Lea Lake outlet modifications
Penn Avenue sinkhole investigation and rehabilitation
UMore Park environmental services
Oxbow-Hickson-Bakke ring-levee flood protection
Development of sewer plan and update of model
Upper Sheyenne River erosion and sedimentation risk assessment
Bathymetry and sediment studies for dredging and restoration of Minnesota lake
Water supply sustainability study for City of Rochester
Natural resources inventory and stewardship recommendations
Water-quality modeling and mapping for watershed district
Landslide stabilization design for an underground coal mine
Infiltration updates to the Minnesota Stormwater Manual
Stormwater storage facility for major Minneapolis interstate artery
Retrofit design for a city-campus parking lot
Water-quality and sediment-dredging study to restore a phosphorus-impaired lake
Advanced oxidation process pilot evaluation for municipal drinking-water system
Rapid response planning for aquatic invasive species
Greenway design to treat stormwater and mitigate flooding
Inspection, design, and construction oversight for tunnel rehabilitation
Stormwater retrofits along redesigned urban streets
Assessment and remediation of former dump site on university campus
Reciprocating internal combustion engine (RICE) applicability analysis and audit
Inspection and repair of urban stormwater tunnels
Responding to wind-farm tornado damage
Updating of Lake Superior chemical source inventory
Earthen embankments reduce flooding and sediment loading in rural creek
Upgrade of wastewater treatment system
Bridge movement monitoring
Evaluation of wind-turbine foundation following fire damage
Project prioritization tool for Minnesota watershed district
Natural resources master plan
Embankment stabilization along Highway 73
Vulnerability assessment of municipal stormwater system
Vulnerability assessment of a city’s aging storm sewer system
Flood-control modeling and system upgrades in urban neighborhoods
Groundwater modeling for wellhead-protection-plan amendment
Multi-site PFAS remedial investigation and remediation
Sediment removal from beneath Vermillion River bridge
Flood forecast mapping for city's emergency response and planning efforts
Sustainable site design for watershed district headquarters
Living-streets planning provides framework for alternative street reconstruction
Improvements to municipal flood-risk-protection system
Green infrastructure treats stormwater along light rail corridor
Engineering services for municipal wastewater-treatment facility
Groundwater-surface water study of McKenna Lake
West Side Flats park and stormwater design
Powerhouse and turbine replacement at Redwood Falls
Monitoring of end-pit lake at oil sands mine
Highway 55 storm-tunnel inspection
Stormwater management system for Minnesota district
Creation of LID master plan for stormwater management
Modeling and failure risk assessment of a municipal storm sewer system
XP-SWMM model update and calibration for Minnesota watershed
Demonstration rainwater gardens reduce stormwater runoff
Flood risk reduction of suburban lakes
Letter of map revision for Minnesota city
Options study and design to restore biomass fuel-handling system
Mine remediation and reclamation
Infrastructure inspection program for Minnesota watershed district
Discovery Point ecological restoration
Hiawatha Golf Course alternatives analysis and master planning
Identification of wetland restoration opportunities
Investigation and design for Freeway Landfill
Stormwater basin retrofits for water quality improvement
Watershed management planning for Minnesota watershed district
Whitewater State Park stream restoration
Hennepin County sustainable landscape guidelines
Removing dissolved metals from roadway runoff using ferric-oxide filtration
Stormwater-management minimal impact design standards and BMP design calculator
West River Parkway landslide repair
Hydropower facility evaluation and due diligence
Landslide stabilization and corridor repair for state highway
Public-space and sustainable stormwater management decision-making framework
FERC relicensing of Ford Lake Dam
Gate automation for the Soo Locks compensating works
Water quality and ecological improvements to an urban lake
Groundwater compliance assistance for CCR Rule
Stormwater-development reviews for urban WMO
Hydrologic study of North Dakota lake
Design, review, and permitting of mountain-bike park
Natural stormwater-treatment system and park redevelopment
Hydrology and hydraulic modeling of a tunnel system
Floodproofing of utility switchyard
Sweeney Lake and Schaper Pond water-quality improvement
One Watershed, One Plan development for southern Minnesota watershed district
Vapor-mitigation implementation and maintenance at business center
Upgraded levee system manages flood risk for Minot residents
Third-party EIS review of transmission line
Hall's Island and Scherer site reconstruction
Minnehaha Park lower glen restoration
Minnetonka Mills Park design
Flood mitigation at refinery
Wetland replacement assistance for highway project
Environmental support for post-fire cleanup at industrial facility
Design of an LED lighting system for a downtown streetscape
Groundwater-flow model of the Twin Cities metro area
Fast-track realignment of a storm sewer
Remediation and redevelopment of historic dump
Development of a citywide GIS-based stormwater management water-quality model
Lilydale Regional Park stormwater management and slope stabilization
PFOS investigation at municipal wastewater plant
Municipal drinking-water wellhouse evaluation and design
Flood risk reduction for North Dakota city
Shoreline stabilization and restoration of Lake Minnetonka’s Big Island
Stormwater infrastructure management assistance
Restoration of trout habitat in Vermilion River
Response to denatured ethanol release
Aquatic invasive species (AIS) management in a Wisconsin lake
Stormwater-basin retrofits improve water quality and habitat
Evaluating tunnel system pressure
Solar-energy-system compliance
Natural stormwater-treatment system and park redevelopment
Cost analysis for meeting water quality standards
Green infrastructure retrofit of an urban shopping-mall parking lot
Berm-failure study at saltwater disposal well site
Dry Spotted Tail Creek stream restoration
Preliminary feasibility study for PFAS-related water quality concerns
Stormwater-development reviews for an urban watershed district
Urban watershed stormwater-development and permit reviews
Remediation and residential redevelopment of Whitehall Leather site
Rockford dam removal
Regulatory-compliance assistance for Freeway Landfill
Ecological residential development design preserves nature and city growth
Groundwater modeling and remedial improvements at closed landfills
Hall’s Island redevelopment and restoration
City of New Brighton water treatment plant design
Redevelopment services for New Brighton Exchange
Stressor-identification report for an impaired urban stream
Strategic planning for Freeway Landfill
Brownfields redevelopment for Mississippi WMO headquarters
Post-flood stream assessment and natural channel design
Redevelopment assistance for Clyde Iron Works site
Tongue River assessment
Brownfields redevelopment for watershed district headquarters
Preliminary design for PFAS-related drinking-water treatment
Groundwater modeling for water-supply wellfield expansion
Renovation of historic Peavey Plaza in downtown Minneapolis
Redevelopment of former Atlas Cement plant
Aquifer storage and recovery and water sustainability evaluation and implementation
Willow River Dam rock arch rapids design services
Water-quality and structural monitoring for channel dredging
Spillway redesign at Cedar Falls Hydro Generating Station
Flood risk management system upgrades and FEMA certification
PMF modifications at hydroelectric plants
Hastings levee certification
PMF study for the Dead River
Rushford levee system remediation
PFAS mass balance and sample collection
Calculating stormwater fees via remote-sensing technology
PFAS treatment during power plant decommissioning
Acid-generating rock identification and mitigation
PFAS-impacted drinking water response and treatment plant design
Gas processing equipment, outage procedure and fitness-for-service evaluation