Meeting CSO Capture Requirements & Local Expectations in an Urban Environment Greening the Gray

Transcription

1 Meeting CSO Capture Requirements & Local Expectations in an Urban Environment Greening the Gray Bruce G. Munn Principal CC John Marino

2 Presentation outline Program history Clinton CSO Storage Facility Project Project goals Unique features Blending green with gray First year operations / lessons learned Program status

3 Where? Rochester Buffalo Syracuse Albany Scranton Pittsburgh Harrisburg

4 Program history Judgment on Consent signed in 1989 Amended Consent Judgment (ACJ) signed 1998 Capture >85% of average annual CSOs Removal of floatables Achieve water quality standards for bacteria in Onondaga Lake CC John Marino

5 Major projects completed Separated/closed 12 CSOs 4 Floatable control facilities 2 Regional treatment facilities 1 CSO storage facility Syracuse Metro WWTP upgrade 35 projects >$350M

6 County negotiated 4th stipulation ACJ in November MG Clinton CSO Storage operational by December 31, 2013 Incorporation of green infrastructure for further CSO reduction 95% CSO capture by December 31, 2018 Image placeholder

7 Clinton CSO Storage Facility Key project goals/challenges Keep all CSO storage below grade Allow reuse of parking lot above CSO storage Saline ground water up to 80,000 mg/l Comply with BMP s for ground water discharge Be consistent with Save the Rain Program Mitigate local construction concerns Begin operations by 12/31/13

8 Facility layout 84 West Jefferson St. Conveyance 30 West St. Conveyance 96 West Onondaga St. Conveyance

9 Construction geotechnical Jet grouting cylinders 70 feet below grade were used to create a base of the bathtub for the excavation area jet grout

10 Construction Diaphragm wall was used to construct east/west influent chambers

11 Soldier pile supported slurry walls Slurry wall construction was used to build reinforced concrete walls for the bathtub and the East and West Chambers

12 Tunnels Three rectangular box tunnels were constructed by open excavation

13 Construction project completion 20,000 cy of concrete 6.5 million gallons of storage volume 180,000 gpm effluent pumps 2,500 gpm dewatering pumps Three (3) 25,000 gallon flushing tanks 75,000 gallon storm water holding tank

14 Design approach for Green roof Sedum cuttings/vegetated matts Stormwater capture/reuse Bioswales

15 Design approach for Energy saving LED CSO storage Reduce the annual electrical consumption by more than 29,000 kw per year, saving the facility $3,800 per year CSO storage design saved $190,000/year pumping cost

16 Facility startup challenges Hydraulic testing of structures Where to you get 6.5 million gallons of water for testing? Mechanical equipment startup How do you test a 60,000 gpm effluent pump? System performance period Three complete CSO events or 12 months Facility outfall to Onondaga Creek with two effluent pumps operating

17 Operation to date Total event data (2014 & 2015 Q1, 2) Number of events 58 Total CSO retained (MG) 127 Total rainfall (inches) 36.7 Facility overflow (MG) 154 Capture Per CSO Event (GAL) 7,000,000 6,000,000 5,000,000 4,000,000 3,000,000 2,000,000 1,000,000 CSO event distribution Total rainfall per cso event (in)

18 Lesson learned flooding Facility flooding event March 2014 Onondaga Creek Typical Flow 200 cfs Rain and Snow Melt Caused Flood Event of 3,000 cfs Highest Recorded Flow Since 1982

19 Lesson learned flooding Flood event operations Use automated pump controls Use the influent sluice gates to isolate the facility Install low headloss check valves on CSO outfalls

20 Lesson learned cleaning Tunnel cleaning 30,000 gallon flushing tanks provided for each tunnel 850-foot long tunnels have 0.5% slope One year tunnel inspection showed minor grit buildup in only one isolated location First flush of tunnel #1

21 Lesson learned cleaning Hose monitors are effective for chamber cleaning A total of 7 monitors are positioned to cleanout the chambers Fixed flushing nozzles are installed around the intakes of the effluent and dewatering pumps to remove grit buildup Cleanup of West Chamber

22 Lesson learned grit removal Hydraulic clamshell buckets works well for removing grit and debris from grit sump Grit removal process is slow due to the 60-foot depth and time of travel Total of 307 cy of grit removed in 2014 Nature of grit varied throughout the year Considered installing a grit pump and cyclone to speed grit removal

23 program status CSO compliance % capture Deadline Stage /31/13 Actual /31/13 Stage /31/ Green infrastructure projects to date 13 CSOs eliminated $600M+ expended to date

24 Project team acknowledgement Onondaga County Department of Water Environment Protection Joanne M Mahoney, County Executive Matthew J Millea, (previous) Deputy County Executive Tom Rhoads PE, Commissioner Nicholas Capozza, Project Manager Environmental Engineering Associates, LLP GHD O Brien & Gere ARCADIS CDM/C&S joint venture Construction Management Jett Industries/Kiewit Construction General Contractor

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