Alexandria Wastewater Program (Phase I)

Alexandria’s sewer and stormwater networks, pumping stations and treatment plants were old and deteriorating. Sewer breaks were frequent and untreated sewage flooded into the city streets. Raw sewage was directly discharged into the Mediterranean Sea polluting both the sea and the beaches. To address such critical situation, a phased implementation plan was initiated by the Government of Egypt and funded by the USAID to improve and expand Alexandria’s wastewater system.

ECG, in joint venture with two global US consultants Metcalf & Eddy and CH2MHill, designed and supervised the construction of pumping stations, two major treatment plants, two bored 21 km tunnels, 1,200 mm dia. each, under-crossings, force mains, collectors, sewer networks, sea outfalls, drain improvement, sludge disposal facilities and mechanical sludge dewatering facilities.

From 1980 to 1995, the following sub-projects were implemented under the Wastewater Upgrade Programme (Phase I):

• Review and update of Alexandria Wastewater Master Plan up to the year 2000. This review included in-depth feasibility study for re-use of treated wastewater to develop an agricultural area: 70,000 acres. The review also considered the disposal of primary treated wastewater effluent through sea outfalls.
• Field investigations included comprehensive soil investigations and survey programmes. The survey comprised land survey and aerial photography, 750 km². Works also comprised ground control of horizontal and vertical stations tied to the national second-degree network and mapping in scales: 1:1000, 1:500 and 1:5000.
• Abu Qir Force Main: 1.2 km, 450 mm dia.
• Sidi Bishr Force Main: 1.3 km, 1,000 to 1,200 mm dia.
• Smouha Force Main: 1.7 km, 600 to 1,800 mm dia.
• East Zone Force Main: 5.5 km, double line and 1,500 to 1,800 mm dia.
• Smouha Collectors: gravity sewers 6.1 km, 200 to 2,750 mm dia. and associated manholes.
• Sidi Bishr Collectors: gravity sewers 4.3 km, 1,200 to 1,500 mm dia. And associated manholes.
• Abu Qir Collectors: gravity sewers 6.7 km, 300 to 1,500mm dia. and associated manholes.
• Smouha Sewage Networks: gravity sewers, 11 km, 200 to 900 mm dia. and associated manholes.
• Abu Qir Sewage Networks: gravity sewers, 32 km, 200 to 800 mm dia. and associated manholes.
• El Siouf ElKeblia and Hagar Elnawatiya Sewage Networks: gravity sewers, 8 km, 200 to 800mm dia. And associated manholes.
• Hydrodrome Drain Improvement: New transition structures and appurtenances.
• Smouha Drain Improvement: Addition of new sewers, manholes, junction boxes, transition structures and appurtenances. New East Zone Pumping Station: 21m deep, max. lifting capacity 600,000 m³/day. For dry construction: 20 m long steel sheet piles were driven to form 54 m dia. circular cofferdam.
• New Smouha Pumping Station: 17m deep, max. lifting capacity 340,000 m³/day. For dry construction: 20 m long steel sheet piles were driven to form a 45 m dia. circular cofferdam.
• New Sidi Bishr Pumping Station: 13m deep, max. lifting capacity 165,000 m³/day.
• New Maamoura Pumping Station: 12m deep, max. lifting capacity 100,000 m³/day. For dry construction: 20m long steel sheet piles were driven to form 45 m dia. circular cofferdam.
• An intensive dewatering system was designed and implemented during the construction period.
• Upgrading the East Treatment Plant including new headwork structures, new flow split structure, demolition of existing clarifiers and construction of eight new ones, eight new pumping stations and new on-site employee housing.
• Upgrading West Treatment Plant: New influent pumping station (955,500 m³/day), new headworks, new primary sedimentation tanks, yard piping (200 to 2,750 mm dia.), modifications to existing buildings and new on-site employee housing.
• El Siouf El Keblia and West Zone Tunnels: 21 km, 1,200 mm dia. Tunnel boring machine or shield and jacking equipment according to soil characteristics. All manholes were constructed by caisson sinking methods.
• Smouha and East Zone Undercrossing:
• Smouha force main: Crossing two highways and a double track branch line railroad (by jacking method) and with a canal (by tunnel boring machine).
• East Zone force main: Crossing two highways and a double track main line railroad (by jacking method) and with a canal (by boring tunnel machine).
• Smouha drain: Crossing with two highways and a double track branch line railroad (by jacking method).
• Sludge Disposal Facilities: Grit, scum and screenings of the treatment plants.
• Mechanical Sludge Dewatering Facilities: New sludge equalization tanks, new dewatering pump station with equalization tank, blower and sludge transfer pumps, new dewatering building with sludge feed pumps, belt filter passing polymer system and sludge cake conveyors.