Improving Water Quality With Phosphorus Removal StructuresChad Penn1, Josh Payne1, Delia Haak2, Josh McGrath3 , Jeff Vitale1, and Garey Fox1

1Oklahoma State University 2Illinois River Watershed Partnership 3University of Maryland

Department of Plant and Soil Science

chad.penn@okstate.edu, 405 744 2746

• Loss of dissolved phosphorus (P) from agricultural, horticultural, urban, and recreational lands to water bodies can promote eutrophication.

• Current best management practices are ineffective in reducing dissolved P losses.

• Soils built up with P will continue to release dissolved P in runoff for many years after fertilizer applications cease.

Industrial by-products

Disposal $$

Poor water quality

Highly sorptive

Use industrial by-products as P sorbing materials (PSMs) to

filter pollutants in runoff

+

=

clean water

polluted water

By-product layer with retained contaminant

Periodically replace the spent material

• contaminants are actually removed from watershed

•removal can be quantified for credit purposes

Landfill space

Runoff Filtration Success Stories

Funding provided by

What are the issues? Computer program for designing P removal structuresCurrent Construction

Site hydrology

1. Peak flow rate

2. Annual flow volume

3. Dissolved P level

+Model

P removal & lifetime

1. Target P removal (%)

2. Target lifetime

+

PSM characterization

1. P sorption

2. Safety

3. Physical properties

Design parameters

1. Area

2. Mass of PSM

3. Depth of PSM

Input Output

Plant optimum soil test P level

Chesapeake Bay Watershed, Centreville, Maryland: Poultry farm runoff

• Runoff captured in pond

• Pond drainage filters through metal boxes containing steel slag

• Initially removed 100% of P; cumulative removal to date is 25%

Stillwater, Oklahoma

• Residential and golf course runoff

• Structure treats 150 acres with steel slag

• Initially removed 100% of P

• Cumulative removal to date is 25%

• Currently testing more sorptive material in structure

Green CreekGreen Creek

flowflowdirectiondirection

poultry poultry houseshouses

proposed proposed structure structure locationlocation

Eastern Oklahoma Poultry Farm

• High peak flow rates: 16 cfs

• Runoff from around poultry houses

• Illinois River Watershed

• Currently designing for target cumulative removal of 45% over 1 year

$$

Economic Justification