Queenston Manor Apartments - LID Saves the Day! Justin R. Ring, P.E. EHRA, Inc. jring@ehrainc.com Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Site is 7.4 acres Developer Traditional development requires 4.07 ac-ft of detention volume Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Goal of modern “conventional” drainage is to remove runoff quickly, efficiently and completely Conventional drainage achieves this goal, but requires large infrastructure expense Queenston Manor Apartments LID DRAINAGE REQUIRES A CHANGE OF PERSPECTIVE Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013 EHRA, Inc.

Queenston Manor Apartments HCFCD CHANNEL Typical detention storage 7 residential buildings QUEENSTON BLVD. NORTH Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments LID drainage concepts and principals: decentralize conveyance and detention distributed “micro-scale” practices - spread it out mimic natural drainage processes – time of concentration, infiltration, volume and flow time-tested technology, different application like conventional methods, drainage is still designed to avoid flood damages and support mobility slower does not mean less efficient Queenston Manor Apartments LID DRAINAGE REQUIRES A CHANGE OF PERSPECTIVE Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments HCFCD CHANNEL Raingardens Underground storage Pervious pavement (parking) Vegetated swales QUEENSTON BLVD. NORTH Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments HCFCD CHANNEL LID design spreads drainage throughout site as an amenity Redesign yielded 2 additional buildings 48 more apartment units QUEENSTON BLVD. NORTH Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Hydrology Queenston Manor Apartments Analyzed 2-year (6-hour), 10-year (24-hour) and 100-year (24-hour) events Rational Method Peak Flow for each DA Hydrographs for each DA using Clark’s Method in HEC-HMS Used actual Tc and calibrated Storage Coefficient R to match Rational Method Peak Flow Queenston Manor Apartments Hydrology Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Hydrology Queenston Manor Apartments HYDROLOGY 7.2-ac site divided into 41 “inlet” drainage areas: Pervious pavement sections Vegetated swales Raingardens Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Hydrology Queenston Manor Apartments HYDRAULICS Dynamic routing using EPA-SWMM software System of nodes and links Nodes: Raingardens (storage area) Pervious Pavement (storage area) Manholes/Junctions Links: Underground pipe (6” - 24”) Overflow Inlets Queenston Manor Apartments Hydrology Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Hydrology Queenston Manor Apartments HYDRAULICS 3 outfalls into adjacent HCFCD channel 54 nodes 51 links Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Landscaping Queenston Manor Apartments December 10, 2013 Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Landscaping Engineered Soil Plant Selection Queenston Manor Apartments Landscaping Engineered Soil Plant Selection Winecup Louisiana Iris Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Queenston Manor Apartments Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Conclustion Queenston Manor Apartments Distributed features contribute to more efficient detention storage and land use Engineered soil filter provides dramatically better SWQ benefits compared to conventional “trash rack” Much greater engineering/analysis effort required than conventional route Increased return on investment for developer Queenston Manor Apartments Conclustion Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

More Efficient Land Plan Attractive Development Queenston Manor Apartments NET RESULT More Efficient Land Plan + Attractive Development MORE Product = Happy Client! Conclustion Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013

Thank You – Questions? EHRA, Inc. Civil Engineering Surveying Land Planning Platting Landscape Architecture Hydrology & Hydraulics Construction Phase Services Public Works Bridges & Structures Transportation Planning Low Impact Development for Local Governments and Designers Workshop - Johnson County Stormwater Management Program December 10, 2013