Interceptor Sewer Contract

Contract No.2 - Mullingar Sewerage Improvement Scheme (MSIS)-Interceptor Sewer

Contract Two, which has been completed, consisted of the laying of more than 4 kilometres of new sewers to convey sewage from the existing drainage network of Mullingar to the waste water treatment plant at Clonmore, and to serve the proposed development of Robinstown. Approximately 1 kilometre of the sewer was constructed by tunnelling, to minimise disruption in the town centre and to carry the sewer underneath the main Dublin – Sligo railway line. The first tunnel, 1800mm in diameter, is from near the junction of Clonmore Road and Lynn Road to the Bleach Yard. The second tunnel starts at 1500mm diameter, at the Pearse St. entrance to the Town park, passes beneath the car park beside Supervalue and Texas Mullingar, ending at 1200mm diameter beside the Royal Canal embankment.

This contract had many challenging aspects which include deep open cut excavations, soft ground conditions, several crossings of the River Brosna, a crossing of the Royal Canal and tunnelling beneath the Railway Embankment and the Town centre, using various pipe diameters from 1800mm down to 600mm. Westmeath Co. Co. took advantage of the canal crossing to construct a new culvert for the river Brosna to alleviate flooding, and also had a new pedestrian underpass constructed to replace the old one.

The route was selected to minimise the impact on the Town, residents and business community of Mullingar. Considerations such as disruption to Traffic, Residents and Businesses, ground conditions, proximity to buildings, archaeology, ecology, crossing of roads, streets, rivers, railway lines, canals, existing services and public amenities, all played an important role in the route selection.

The main components of the Interceptor Sewer Contract are as follows: -

  • Construction of the main Interceptor Sewer (600mm to 1800mm dia.) from Springfield / Robinstown to the Lynn Road Pumping Station.
  • Decommissioning of existing Bleach Yard Pumping Station.
  • Interception of spills from ten Combined Sewer Oveflow points.
  • A 750mm dia. sewer in Mount Street / Bleach Yard.