Niroth water treatment plant

As compared with the rest of Cambodia, Phnom Penh, the capital, is well-supplied in drinking water. However, this city with a population of 1.6 million is adversely impacted by uneven access to drinking water from one community to the next – a problem aggravated by its fast-paced population growth and industrial development. In response to this situation, the Phnom Penh Water Supply Authority (PPWSA) decided, as part of its 2005-2020 Master Plan, to build a new treatment plant in Niroth to produce drinking water. The project includes a water-intake system in the Mekong River, a raw-water pumping station, a filtration facility, and a treatment plant that feeds potable water into the city’s distribution system. Given the project’s considerable scope, a decision was made to divide it into two phases, with each phase encompassing a capacity of 130,000 cubic metres a day. A call for tenders was issued for each phase, and VINCI Construction Grands Projets won the call for tenders for the second phase in 2014, one year after the entry into service of the initial phase.

BACKGROUND

To keep pace with population growth in Phnom Penh, the PPWSA was restructured in the early 1990s. In the last eight years alone, demand for water in this city has doubled.
Since 1993, the restructured PPWSA has increased its supply of drinking water sevenfold, reduced losses by a factor of ten, and multiplied sales by 24. Niroth is the city’s fourth-largest plant in terms of size and its leading plant in terms of production. Its input raises overall production from 300,000 to 560,000 cubic metres a day.

TECHNICAL OVERVIEW

The treatment plant project includes installation of pumping equipment (four new 160-kW pumps) where the existing water-intake system is located. The new treatment plant includes construction of 12 plate settlers with four coagulation chambers and 12 flocculation chambers. Also, construction of dosing and storage facilities for reagents (lime and aluminium sulphate), 12 sand filters, and a semi-underground treated-water storage tank with a capacity of 23,000 cubic metres.
The infrastructure will also feature new chlorination equipment in the existing chlorination building, electrical cabinets and wires, automation systems and SCADA applications, six new 500-kW pumps for treated water in the existing pumping facility, two 50-cubic-metre surge-control tanks, interconnection pipes (cast-iron pipes ranging in diameter from 600 to 1,200 millimetres), and drainage networks. Implementation of the new plant and its connection with the existing plant are both integral parts of the contract.
The foundations for all structures will consist of 1,056 piles, 400 x 400 millimetres at the pilehead and 22 metres long. This is the first water-management construction project for VINCI Construction Grands Projets in Cambodia. It is also one of our largest projects calling for the construction of a drinking-water treatment plant.

The structure is fully automated and is equipped with pumps that can operate at variable speeds, resulting in greater energy efficiency.

IMPACT

Thanks to this project, VINCI Construction Grands Projets is contributing to improving water supply in Phom Penh by doubling the capacity of the Niroth treatment plant, located in the southern districts of the Cambodian capital. This new facility is designed to enhance the city’s ability to provide safe, high-quality water to the population. The Niroth plant is designed to meet the strong increase in demand, which is tied to demographic and industrial growth in and around Phnom Penh. The objective is to double the capacity of the existing plant, thereby enabling nearly 400,000 people (that’s a quarter of the city’s population) to gain access to drinking water.
The new drinking-water production plant in Niroth reflects the dynamic growth that Cambodia has experienced in the past several years and the authorities’ willingness to provide access to basic services such as potable water. Finally, this project also illustrates how VINCI Construction Grands Projets projects contribute to international development through a diversity of construction initiatives: in Cambodia, the Company has also worked to expand air terminals in Phnom Penh and Siem Reap for Cambodia Airports.

Project participants

Client
Phnom Penh Water Supply Authority (PPWSA)

Project management
Safège

Key figures

Implementation dates
September 2014 to March 2017

Concrete
13,500 m3

Steel
2,600 t

Earthworks
26,000 m3

Rehabilitating and expanding the drinking-water treatment plant

Kantale

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