mapshed model for the christina basin · farm animal population • used usgs in -stream monitoring...

VUSP Symposium October 14, 2015

Using MapShed Model for the Christina Basin TMDL Implementation and Water Quality Restoration Dani-Ella Betz Chester County Water Resources Authority Dr. Barry Evans Penn State University Stroud Water Research Center Appreciation for PA DEP funding and technical assistance

VILLANOVA

Delaware County

Lancaster County

State of Delaware

Montgomery County

Project Goals

Tool to assist with 2006 Christina Basin TMDL sediment, bacteria, nitrogen and phosphorus TMDL 565 sq. miles TMDL NOT watershed-wide

After a comparison of models, we chose MapShed. GIS-based watershed modeling tool Worked with Barry Evans to localize and calibrate

the MapShed model for the Christina Basin

• Chester County Enhanced Input Data: Land Use (1995 and 2010) Weather Water Extraction Septic Systems Farm Animal Population

• Used USGS in-stream monitoring stations to

calibrate Brandywine, Red Clay and White Clay

MapShed for Christina Basin

EPA TMDL Loading Rates – Sediment (TSS)

-

500

1,000

1,500

2,000

2,500

3,000

3,500

Bas

elin

e Lo

adin

g R

ate

(kg/

ha/y

r)

Christina Basin TMDL - HSPF Model Watersheds Baseline Sediment Loading Rates

Sediment Loading Rate

Attenuation

Wetlands, ponds, impoundments behind dams influence loading rates.

Reduces pollutant loads at watershed 0utlet, but hides influence of “hot spots” Source: Merritts, Franklin&Marshall College

Baseline Scenario: 1994- 1998 (TMDL developed) 2012 Current Scenario: 2010-2012 updated land cover that

revised loading rates incorporating land conversion and any known BMPs implemented state-compiled government data at county-level

MapShed for Christina Basin

Future Scenarios: What combinations of BMPs can achieve the TMDL percent reduction needed?

MapShed for Christina Basin

Results for Brandywine Modeled 15

Brandywine TMDL sub-basins that had WLA

Greatest source of pollutants in 2012 scenario

Future bmp implementation scenario

Source of Pollutants 2012 Land Use & BMPs

Municipal Reductions Required

Future BMP Implementation Scenario

Data inputs per basin

Future Scenario Results

Current Application

W. Goshen Township TMDL Strategy for Brandywine Creek and Chester (Goose) Creek Used MapShed baseline sediment loading Input existing detention basins Able to meet requirements with proposed suite

of bmps, including significant investment in stream restoration

Future Applications

Assist municipalities to determine future effort required to meet TMDL .

Potential tool to evaluate financial investment and decisions William Penn Foundation ‘s SWAT (Soil and Water

Assessment Tool) will be compared to MapShed.

Use of MapShed to track water quality

restoration progress watershed-wide.

For More Information

MapShed Model (NOT MapShed for the Christina Basin): http://www.mapshed.psu.edu/ Christina Basin MapShed: Contact Dani-Ella Betz at Chester County Water Resources Authority