The project consists of the construction of the Wastewater Treatment Plant, 6 km of sanitary sewage networks in Burunga, three pumping stations, two load-break chambers in the pressure network, 6,227 m2 of built area to house the operation and maintenance services, general administration and laboratory services, workshops, industrial buildings for the treatment process, buildings for electrical installations, a guardhouse for surveillance of the pumping stations and civil works for site development: dirt roads, roads, lighting, rainwater system and landscaping, all within a budget of 85 million euros.
The Arraiján Este treatment plant is designed with a water line composed of:
- Raw water elevation
- Raw water feed and general bypass by 40” GRP piping.
- Removal of fines by self-cleaning sieve filter
- Grit removal and grease separation in aerated channel
- Flow measurement by bypass and electromagnetic flowmeter system
- Active sludge biological treatment including nutrient removal, with nitrification and denitrification and removal of phosphorus.
- Secondary decantation
- Filtering by 20-micron mesh discs
- Disinfection by UV radiation in channel
- Treated water tank and clean water tank
- Flow measurement and disposal of treated wastewater into the Aguacate River.
The excess sludge line consists of: screening on a rotary sieve drum, thickening on thickening tables, mixing pond, pumping of mixed sludge for anaerobic digestion, ferric chloride dosing for phosphorus removal, pH regulation with slaked lime and digested sludge buffer tank. Production and storage of gas in a diaphragm gasometer, excess gas combustion flare, gas blowers to conduct the digester gas to the boiler, sludge heating system consisting of a hot water boiler with a dual gas and gas-oil burner, spiral heat exchangers and gas suppressors are also included in the design brief.
The contract includes the design of both the first construction phase of the wastewater treatment plant and its projection to 2050. The plant’s treatment capacity for this horizon year will be 86,400 m3/day (1 m3/sec) in five active sludge treatment and anaerobic digestion modules. The contract also includes calculation and design of the trunk conduit system and its connection with existing networks. Aqualia will take care of the construction of phase one — composed of three treatment modules with a capacity of 53,568 m3/day (0.62 m3/s) — and O&M of the same for the first 10-year concession period.
The plant will be located in Nuevo Chorrillo in the township of Cerro Silvestre on the right bank of the Aguacate River, on a plot of land with an area of approximately 19.5 hectares.
The Fundavico, Montevista, Altos de Cáceres II, Brisas del Sol, Colinas del Sol, Nuevo Chorrillo and Lluvia de Oro 1 housing estates, which are currently endowed with a sanitary sewerage system, will be the first to connect to the new WWTP by the interconnection collectors and the newly designed trunk system (pressure network). The estimated construction period of the plant is three years.
This project was financed by the Andean Development Corporation (CAF) and the Government of the Republic of Panama.
