Project Outline

Under this design, build and operate (DBO) contract Murphy delivered a new water treatment plant to serve the town of Arklow and its environs. The project entailed delivery of the following:

  • A new water treatment plant with a production capacity of 6.1MLD over 20 hours.
  • 14 no. raw water abstraction boreholes.
  • 1 no. surface water abstraction point at Goldmines.
  • Treated water supply pumping station.
  • Decommissioning and demolition of obsolete infrastructure.
  • Operation and maintenance of the completed facility for a period of 20 years.

Key Challenges

Raw water supply is primarily sourced from boreholes but has the facility to draw up to 40% from the surface water intake at Goldmines depending on conditions.

Our design delivered the flexibility to overcome changes in raw water sources by incorporating parallel treatment streams.

These streams cater for the varying characteristics between surface and borehole water without and ensure output is not disrupted.

Project Delivery & Innovations

The design-build solution delivered by Murphy included:

  • 14 no. raw water abstraction boreholes.
  • 1 no. surface water abstraction point at Goldmines.
  • Chemical storage, dosing and mixing system for coagulation, two-stage flocculation, pH correction, preliminary oxidation of soluble iron and manganese and chlorination.
  • Dissolved air flotation (DAF) on stream for surface water supply.
  • Rapid gravity sand filters.
  • High lift pumps and surge protection for treated water feed to Lamberton Reservoir.
  • UV disinfection of treated water for deactivation of cryptosporidium.
  • Water quality monitoring on raw and treated water.
  • Sludge thickening and dewatering facilities.
  • EICA installation including SCADA system and communications links to allow abstraction points.
  • Decommissioning and demolition of obsolete infrastructure.

Murphy will operate and maintain this facility on behalf of Irish Water until 2035.

Key Facts 

The new infrastructure was delivered without any outages or interruption to the water supply.