1. An Overview of the GWK Retention Treatment Facility and
The August 11, 2014 Wet Weather Event
August 19, 2014
Tim Minor

2. August 11, 2014 Wet Weather Event Next Steps
Overview Elements
Brief History of the GWK Drainage District and GWK Retention Treatment Facility
Design
Operations
August 11, 2014 Wet Weather Event
Next Steps
Tim Minor

3. GWK Drainage System OK

4. GWK System Map OK

5. GWK System Map: Clawson VicinityOK
Towards GWK RTF

6. GWK RTF Design: Criteria
The GWK RTF is a Pollution Control Facility that screens out sanitary trash and other solids and provides disinfection using chlorine before discharging to the Red Run Drain.
Chlorine contact time and wet weather volume storage provided using the 124 Million Gallons of storage capacity available in the facility.
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7. GWK RTF Design: Criteria
Designed to address flows from a 10-year, 1-hour design event. Peak flow rate into the GWK RTF ≈ 3.1 Million Gallons per Minute (7,000 cfs).
GWK RTF construction and upgrades were required to reduce Combined Sewage Overflows (CSOs) and be in compliance with MDEQ rules and the Federal Clean Water Act.
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8. GWK RTF Design: Extent of Pollution Control Facility
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9. GWK RTF Design: Original Influent Weir
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10. GWK RTF Operations Explained: Operator’s Walk-through
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11. August 11, 2014 Wet Weather Event: Event Statistics
WRC has a network of rain gauges that provide rainfall depth from every wet weather event.
Rain Gauge 0880 is located at the GWK RTF and is used to determine rainfall amounts for much of the GWK RTF service area.
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12. Rainfall frequency is determined by referencing published texts.
August 11, 2014 Wet Weather Event: Event Statistics
Rainfall frequency is determined by referencing published texts.
At the time of the GWK RTF design “Technical Paper 40” was a reference text.
Today. “NOAA Atlas 14” is the reference text.
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13. August 11, 2014 Wet Weather Event: Radar Rainfall
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14. August 11, 2014 Wet Weather Event: Radar Rainfall
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15. August 11, 2014 Wet Weather Event: Comparison to Design Event

16. August 11, 2014 Wet Weather Event: Effect on GWKDD and RTF

17. August 11, 2014 Wet Weather Event: Effect on GWK RTF

18. August 11, 2014 Wet Weather Event: Effect on GWK RTF

19. Red Run at GWK Outlet (Dequindre)
August 11, 2014 Wet Weather Event: Effect on Red Run Drain
Red Run at GWK Outlet (Dequindre)

20. August 11, 2014 Wet Weather Event: Effect on Red Run Drain
Red Run at Mound
Red Run at Van Dyke

21. Collect community data from basement flooding
August 11, 2014 Wet Weather Event: WRC Next Steps
Collect community data from basement flooding
Hydraulic study of the GWK facility
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22. Oakland County Executive Office Announcement
“The flooding impacted thousands of individuals who now have many questions about how to recover from this disaster. The Multi-Agency Resource Center (MARCs) will be an opportunity to meet with experts who can answer some of those questions.”
– L. Brooks Patterson
The Southfield MARC will be open 11 a.m. – 7 p.m. Wednesday and Thursday at the Southfield Pavilion, Evergreen Road south of the I-696 expressway.
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