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

2. 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

3. 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.

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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

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

13. 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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

28. 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

29. 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

30. 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