UPGRADING GAZA WASTEWATER TREATMENT PLANT. Gaza City is populated with 550,000 inhabitants and it forms 45% of the Gaza strip population.

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1 Gaza City Gaza City is populated with 550,000 inhabitants and it forms 45% of the Gaza strip population. Gaza City has the oldest wastewater system in Gaza Strip; it consists of some of 280 kilometers of sewer Gaza City daily production of Wastewater is 60,000 cubic meters, only 45,000 cubic meters (75% of the produced wastewater) is pumped to the existing wastewater treatment plant.

2 History of GWWTP: 1977 Two pond treatment system (Existing Anaerobic ponds) UNDP added two ponds (Existing Aerated pond and Polishing Pond 12,000 m 3 /d) UNRWA rehabilitated the facilities without increasing the capacity USAID upgraded and expanded GWWTP to handle 32,000 m 3 /d (Existing Situation of the treatment plant)

3 GWWTP Salah Al Deen Road

4 GWWTP NOW:

5

6 Dimensions and volume of Existing basins: Anaerobic Ponds 1 &2 60 X 50 m Bottom, 91.2 x 81.2m Top Water Depth 4.3 m, Volume 20,000 m 3 each Effluent Polishing Pond 64 x 47 m Bottom, 99.2 x 63.4m Top Water Depth 4.5 m, Volume 20,600 m 3 Anaerobic Ponds X 42 m Bottom, 164 x 76m Top Water Depth 5.2 m, Volume 32,000 m 3 Aeration Pond 150 X 42 m Bottom, 184 x 76m Top Water Depth 4.6 m, Volume 38,000 m 3 No. of Mech. Aerator 16 (6-50HP & 8-25, 2 spare) Settling Channel / Pond 66.4 m Bottom length, 13.5m Top width Water Depth 5.8 m, Volume 2,200 m 3 Bio Towers (2 No.) m Diameter, 7.32 m Filter Media Height Volume 3,862 m 3 each Sludge Holding Pond 51.1 X 17.7 m Bottom, 85 x 51.7m Top Water Depth 4.5 m, Volume 2,800 m 3 each Sludge Holding time 9 days Sludge Drying Beds (8 N0.) X 12 m Bottom, x 24m Top Water Depth 1 m, Daily Sludge Loading 311 m 3 /day, Drying time 10 days

7 PROCESS SCHEMATIC DIAGRAM

8 Wastewater Characteristics - GWWTP CRITERIA Upgrading Existing New Upgrading Year 1998 Year 2008 Design flow 32,000 m 3 /d 45,000 t0 55,000 m 3 /d 75,000 m 3 /d Process 90,000m 3 /d Hydraulic Average BOD Influent 378 mg/l 500 mg/l 500 mg/l TSS Influent 750 mg/l 470 mg/l 500 mg/l COD Influent 810 mg/l 1000 mg/l 1000 mg/l BOD Effluent 50 mg/l 70 mg/l * 60 mg/l > 250 mg/l ** TSS Effluent 50 mg/l 70 mg/l * 60 mg/l > 250 mg/l ** * :Treatment Plant facilities completely on operation ** :Treatment Plant facilities Partially on operation

9 Gaza Central Wastewater Project - KFW 1. Construction of the new Buriej WWTP adequate up until 2025, Expected Stage 1 to come into operation in 2008???. 2. Construction of Wadi Gaza Central Pump Station (CPS). 3. Construction of DN 1400 pressure main from Wadi Gaza CPS to Buriej WWTP. 4. Construction of the DN 1500 Gaza City collector to divert the wastewater from GWWTP to Wadi Gaza CPS. 5. Connection of newly constructed Central Communities Gravity Collector to CPS via crossing under Wadi Gaza. 6. Procurement of Operation equipment for the pumping station, the treatment plant and excess sludge disposal.

10 Gaza Central Wastewater Project - KFW GWWTP Salah Al Deen Road CPS Buriej WWTP

11 Inlet Structure Oil and Grease Holding Tank Dewatering Screens Primary Sludge to SHT To Sludge Processing Units RAS - Return Activated Sludge WAS - Waste Activated Sludge SST - Secondary Settling Tank AST - Activated Sludge Tank SHT - Sludge Holding Tank Aerated Grit & Grease Removal RAS RAS/WAS pumps WAS Primary settling Tanks AST1 AST2 SST1 SST2 Distributer 2 Distributer 1 AST3 AST4 SST3 SST4 Buriej Wastewater Treatment Plant To Wadi Wetland Polishing

12 Buriej Wastewater Treatment Plant Inlet Structure Screens (Slit 6 mm, 3 channels at stage 1 and 4 at stage 2). Aerated Grit and Grease Removal. Sand Classifier. Oil and Grease Holding Tank Primary Sedimentation Tanks (4 units in stage 1 and 6 in stage 2 Rectangular section 73 m length, 1500 m 3 capacity). Distributer 1 Activated Sludge Tanks (4 main lines at stage 1 and 7 at stage 2, 113.8m length and 5.6m water depth, 100,000 m 3 total volume in stage 1). Distributer 2 Final Sedimentation Tanks (4 Circular at stage 1 and 6 at Stage 2, 60 m Diameter, 3.8 m depth)

13 Buriej Wastewater Treatment Plant - Continue Wadi Wetland Polishing. Emergency overflow, Bypass System. Blower Station. Sludge Treatment Units Return Sludge and Waste Activated Sludge Pumping Station. Sludge Thickeners Sludge Storage Tanks Mechanical Dewatering Units Emergency Sludge Storage Bay. Sludge Stacking Area. Emergency sludge Lagoons

14 Objectives of Rehabilitation Works 1. Ensure an environmentally sound and hygienically safe treatment of sewage and reduce health risks to the population of Gaza City and close communities in the center of Gaza Strip by: Increasing Hydraulic and Treatment Capacity. Better effluent Quality. 2. Contribute towards protecting the regional groundwater resources by: Reuse the treated Wastewater in Agricultural Infiltrate the treated wastewater.

15 Proposed Emergency Works 1. Upgrade GWWTP to treat 75,000 m3/d. (following Slide). 2. Upgrading of Pumping station no. 1 Construction of a station wet pit and replace the existing three variable speed motors pump by another fix speed pumps with a suitable capacities Modifying the electrical panel. Replacement of the 24 Asbestos pressure line by a 24 cement lined steel pipes. 3. Construction of Pumping Station No Construction of force main from PS3 to PS11 5. Construction of Sewer networks in Tal El Hawa and El Sheikh Ejjlien Area.

16 GWWTP Upgrading Inlet Chamber Sand Removal BOD 5 500mg/l COD 1000 mg/l TSS 500 mg/l Anaerobic pond 1 Anaerobic pond 1 Anaerobic pond 3 Anaerobic pond 4 Sludge Two Bio Towers Oxygen Supply Aerated Pond Two Bio Towers Sludge Existing Facility Polishing Lagoon Under Construction with Settling channel Existing Pressure line Proposed Upgrading BOD 60mg/l 5 COD 200 mg/l Exis. Pump Station TSS 60 mg/l Proposed Pressure line

17 GWWTP NOW: Sand Removal Inlet Chamber New Sludge D.B. Settling Channel New Sludge D.B. Anaerobic pond 3 New Bio Towers