1. Purdue Status Report Summer Meeting 2012 Midwest Spatial Decision Support Interest Group Region 5 EPA July 9, 2012 Bernie Engel, Larry Theller, Youn Shik Park, Laurent Ahiablame. Agricultural and Biological Engineering Purdue University

2. Topics L-THIA LID improvements Fox River Project update (L-THIA Owls)

3. Effectiveness of low impact development practices in two urbanized watersheds: Retrofitting with rain barrels/cisterns and porous pavements Laurent Ahiablame Prof. Bernard Engel, Prof. Indrajeet Chaubey

4. 4  How effective are LID practices at the watershed scale?  LID practices - lot level control measures  Current focus of research – runoff management with LID practices.  Impacts of LID practices on baseflow need to be investigated  at the lot scale  at the watershed scale The Problem

5. How to Proceed?  Monitoring – most appropriate (perhaps), expensive, time consuming, sometimes impossible.  Modeling – convenient, less expensive, time efficient, sometimes may be complex.  Modeling – L-THIA-LID

6. L-THIA Modeling of LID Practices  Standard procedure for LID modeling  Representation of LID practices  CN values  Consideration of design guidelines  Sizing factors  Computation of runoff, baseflow, total flow  Threshold area: IF watershed area ≥ 120 ha => baseflow  Computation of LID effectiveness index  Baseflow core equation  Regression model for Indiana conditions  Relationship between baseflow and LID practice  BFI versus CN  Baseflow pollutant coefficients

7. Improving L-THIA-LID  LID practices currently represented in L-THIA-LID  Bioretention/rain garden  Open wooded space  Porous pavement  Swale  Porous pavement + swale  Permeable patio  Green roof  Disconnected impervious surfaces

8. Improving L-THIA-LID L-THIA-LID Interface (VBA) Runoff (distributed approach) Baseflow LID Effectiveness Index

9. Little Eagle creek Little Buck creek Little Eagle Creek Little Buck Creek Land useArea (ha)Percent Area (ha)Percent Low Density Residential3872.854.83273.074.1 Commercial/Industrial2260.232.0538.912.2 High Density Residential271.03.81.40.0 Road/Street573.68.1366.38.3 Bare soil16.00.2-- Grass/Pasture77.41.1238.25.4 Total7070.9 4417.7 ScenarioDescription S1existing condition S225% rain barrel/cistern S350% rain barrel/cistern S425% porous pavement S550% porous pavement S6S2 + S4

10. Little Eagle Creek Flow (%)TP (%)TN (%) Runoff Scenario 2656 Scenario 311 12 Scenario 4333 Scenario 5556 Scenario 6889 Baseflow Scenario 2 Scenario 3-2 Scenario 4 Scenario 5 Scenario 6-2 Total flow Scenario 2253 Scenario 3596 Scenario 4121 Scenario 5243 Scenario 6475 LID Scenario Runs: 1991-2010 Effectiveness of LID practices

11. Little Buck Creek Flow (%)TP (%)TN (%) Runoff Scenario 2323 Scenario 3556 Scenario 4444 Scenario 5878 Scenario 6767 Baseflow Scenario 2000 Scenario 3 Scenario 4 Scenario 5 Scenario 6 Total flow Scenario 2121 Scenario 3243 Scenario 4232 Scenario 5464 Scenario 6353 Effectiveness of LID practices LID Scenario Runs: 1991-2010

12. Summary  Simulated runoff, baseflow, and total flow for the baseline compared well with observed values during calibration and validation periods.  Calibration: R 2 and NSE > 0.5  Validation: R 2 > 0.4; NSE > 0.3  Effectiveness of LID practices at the watershed scale  Runoff + pollutants: 2 to 12%  Baseflow + pollutants: -1 to -2%  Total flow + pollutants: 1 to 9%  Good LID options for retrofitting in urbanized watershed  25% rain barrel/cistern adoption  25% porous pavement adoption  25% rain barrel/cistern + 25% of porous pavement adoption

13. “Fox River” Project Corps 516(e) project is collaboration with Michigan State University Institute of Water Research. Tools work together behind the interface. High-resolution data for 4 Priority Watersheds. Medium-resolution data for entire Great Lakes area.

14. Extends L-THIA online tool to entire Great Lakes area.

15. Floating, semi-transparent toolbars, collapsible menus, open architecture for partners, improved editing performance. New Area of Interest tool : Polygon “Select by HUC” to use a single HUC 12, 10, 8 outline.

16. Tool will now allow use of a polygon as an area of analysis. This will improve ability to model zoning and LID BMP areas.

17. -Display of HIT target layers -EPA Waters layers -GIS layers -Multi-resolution data layers

18. New Results Options