County of Nassau Department of Public Works Bay Park Sewage Treatment Plant Super Storm Sandy Recovery Edward P. Mangano County Executive Shila Shah-Gavnoudias, P.E. Commissioner of Public Works
Bay Park Sewage Treatment Plant General Background Information Bay Park Sewage Treatment Plant originally constructed in 1949. Major expansions and upgrades during 1960 s and 1980 s. Current permitted capacity is 70 MGD. Current average daily wastewater flow is 50 MGD. The plant serves a population of approximately 550,000. 2
SUPER STORM SANDY IMPACT 3
4
Bay Park Sewage Treatment Plant Super Storm Sandy Impact and Recovery On October 29, 2012, as a result of Super Storm Sandy and the accompanying storm surge, at approx. 8 pm the Bay Park STP begins to flood and at approx. 10 pm the Bay Park STP goes off-line. Nassau County immediately mobilizes a team of Public Works employees, engineering consultants and construction contractors to begin damage assessment and restoration of wastewater treatment. The Bay Park STP remains off-line for approx. fifty-six (56) hours. On November 1, 2012, at approx. 6 am, wastewater flow through the Bay Park STP is restored. The initial treatment processes include: raw sewage pumping, influent screening, grit removal, primary settling and disinfection. 5
Bay Park Sewage Treatment Plant Influent Pumping Facility ~ Flooding 6
Bay Park Sewage Treatment Plant Effluent Screening & Disinfection Bldg ~ Flooding 7
Bay Park Sewage Treatment Plant Outfall Tide Pump Facility~ Flooding 8
Bay Park Sewage Treatment Plant Tunnel Access Stairway ~ Flooding 9
SUPER STORM SANDY RECOVERY 10
Bay Park Sewage Treatment Plant Removing Flood Waters 11
Bay Park Sewage Treatment Plant Clean-Up and Disinfection 12
Bay Park Sewage Treatment Plant Documenting and Assessing Damage 13
Bay Park Sewage Treatment Plant Re-Powering and Emergency Repairs 14
Bay Park Sewage Treatment Plant Recovery Timeline for Process Equipment Treatment Process/Equipment Date Influent Pumping/Raw Sewage Pumps Nov 1, 2012 Influent Screens, Grit Removal, Primary Settling and Disinfection Nov 1, 2012 Outfall Pumping/Temporary Pumping System Nov 1, 2012 Aeration Tanks/Process Air Blowers Nov 6, 2012 Sludge Digestion/Digesters, sludge pumps, and gas compressors Nov 12, 2012 Sludge Dewatering/Temporary Dewatering System Nov 12, 2012 Dechlorination System Nov 15, 2012 Primary Sludge Pumping Nov 16, 2012 Outfall Pumping/Effluent Tide Pumps Nov 20, 2012 Secondary Treatment/Final Settling, RAS and WAS Pumping Nov 21, 2012 Sludge Thickening/Temporary Gravity Belt Thickeners Nov 26, 2012 15
October 30, 2012 RAW SEWAGE SEWER SCREENING GRIT REMOVAL PRIMARY THICKENING DIGESTION OFF SITE DISPOSAL DEWATERING TO OUTFALL DECHLORINATION SCREENING & DISINFECTION FINAL AERATION TANKS OUTFALL WAS RAS Process Flow Diagram Bay Park Sewage Treatment Plant 16
November 1, 2012 RAW SEWAGE SEWER SCREENING GRIT REMOVAL PRIMARY THICKENING DIGESTION OFF SITE DISPOSAL DEWATERING TO OUTFALL DECHLORINATION SCREENING & DISINFECTION FINAL AERATION TANKS OUTFALL WAS RAS Process Flow Diagram Bay Park Sewage Treatment Plant 17
November 6, 2012 RAW SEWAGE SEWER SCREENING GRIT REMOVAL PRIMARY THICKENING DIGESTION OFF SITE DISPOSAL DEWATERING TO OUTFALL DECHLORINATION SCREENING & DISINFECTION FINAL AERATION TANKS OUTFALL WAS RAS Process Flow Diagram Bay Park Sewage Treatment Plant 18
November 12, 2012 RAW SEWAGE SEWER SCREENING GRIT REMOVAL PRIMARY THICKENING DIGESTION OFF SITE DISPOSAL DEWATERING TO OUTFALL DECHLORINATION SCREENING & DISINFECTION FINAL AERATION TANKS OUTFALL WAS RAS Process Flow Diagram Bay Park Sewage Treatment Plant 19
November 15, 2012 RAW SEWAGE SEWER SCREENING GRIT REMOVAL PRIMARY THICKENING DIGESTION OFF SITE DISPOSAL DEWATERING TO OUTFALL DECHLORINATION SCREENING & DISINFECTION FINAL AERATION TANKS OUTFALL WAS RAS Process Flow Diagram Bay Park Sewage Treatment Plant 20
November 16, 2012 RAW SEWAGE SEWER SCREENING GRIT REMOVAL PRIMARY PRIMARY THICKENING DIGESTION OFF SITE DISPOSAL DEWATERING TO OUTFALL DECHLORINATION SCREENING & DISINFECTION FINAL AERATION TANKS OUTFALL WAS RAS Process Flow Diagram Bay Park Sewage Treatment Plant 21
November 20, 2012 RAW SEWAGE SEWER SCREENING GRIT REMOVAL PRIMARY PRIMARY THICKENING DIGESTION OFF SITE DISPOSAL DEWATERING TO OUTFALL DECHLORINATION SCREENING & DISINFECTION FINAL AERATION TANKS OUTFALL WAS RAS Process Flow Diagram Bay Park Sewage Treatment Plant 22
November 21, 2012 RAW SEWAGE SEWER SCREENING GRIT REMOVAL PRIMARY PRIMARY THICKENING DIGESTION OFF SITE DISPOSAL DEWATERING TO OUTFALL DECHLORINATION SCREENING & DISINFECTION FINAL AERATION TANKS OUTFALL WAS RAS Process Flow Diagram Bay Park Sewage Treatment Plant 23
November 26, 2012 RAW SEWAGE SEWER SCREENING GRIT REMOVAL PRIMARY PRIMARY THICKENING DIGESTION OFF SITE DISPOSAL DEWATERING TO OUTFALL DECHLORINATION SCREENING & DISINFECTION FINAL AERATION TANKS OUTFALL WAS RAS Process Flow Diagram Bay Park Sewage Treatment Plant 24
TREATMENT PLANT PERFORMANCE 25
35 Bay Park Sewage Treatment Plant Effluent Data Total Suspended Solids (TSS) and Carbonaceous Biochemical Demand (CBOD) Monthly Average (mg/l) 30 25 TSS Permit Limit: 30 mg/l CBOD Permit Limit: 25 mg/l 20 15 10 5 0 Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct TSS Effluent Conc. CBOD Effluent Conc. 26
Bay Park Sewage Treatment Plant Effluent Data Total Suspended Solids (TSS) November Daily Results (mg/l) 120 100 80 60 40 20 TSS Permit Limit: 30 mg/l 0 Permit Limit (TSS) Effluent Conc. (TSS) 27
Bay Park Sewage Treatment Plant Effluent Data Carbonaceous Biochemical Oxygen Demand (CBOD) November Daily Results (mg/l) 350 300 250 200 150 100 50 0 CBOD Permit Limit: 25 mg/l Permit Limit (CBOD) Effluent Conc. (CBOD) 28
Bay Park Sewage Treatment Plant Effluent Data Total Suspended Solids (TSS) December Daily Results (mg/l) 120 100 80 60 FST carry-over of solids; additional PST in-service FST #5 OOS; Drained and Repaired 40 TSS Permit Limit: 30 mg/l 20 0 Permit Limit (TSS) Effluent Conc. (TSS) 29
Bay Park Sewage Treatment Plant Effluent Data Carbonaceous Biochemical Oxygen Demand (CBOD) December Daily Results (mg/l) 140 120 100 80 FST #5 OOS; Drained and Repaired 60 40 20 CBOD Permit Limit: 25 mg/l 0 Permit Limit (CBOD) Effluent Conc. (CBOD) 30
Bay Park Sewage Treatment Plant Effluent Data Total Suspended Solids (TSS) and Carbonaceous Biochemical Demand (CBOD) Removal Percentage 100% 80% 60% 40% 20% 0% Permit Requirement: 85% TSS Removal % CBOD Removal % 31
CONTINUING THE RECOVERY 32
Bay Park Sewage Treatment Plant Recovery Plan ~ Next Steps Completion of Emergency Repair Projects Develop Permanent Repair Projects Identification of Mitigation Measures Extreme Weather and Climate Change Assessment 33