Over the course of the Longford Central RWSS scheme, two works contract were carried out which significantly improved the existing water treatment and water supply infrastructure.
The first contract that was carried out involved the improvement of water treatment facilities at Lough Forbes WTW. Prior to the upgrade, the existing clarification tank was overloaded. This resulted in poor treated water quality. This also led to the more frequent backwashing of filters.
Following the upgrade of facilities, the following positive impacts were realised:
- Improved treated water quality produce at Lough ForbesWTW
- Reduction in the frequency of backwashing, resulting in less backwash pumping and less backwash water being wasted
- No increase in abstraction from adjacent lake (Lough Forbes)
- No works carried out in Lough Forbes or its foreshore
- Improved backwash water settlement, resulting in improved quality of supernatant returning to Lough Forbes.
- New facilities for sludge thickening and drying resulted in lower sludge transport costs
- EcIA was carried out for this project and found that the works would have no significant adverse impact on existing wildlife in the vicinity of Lough Forbes Complex SAC and Ballykenny-
Fisherstown Bog SPA
- Upgrade works were carried out in existing site, without the need for increased land area
The second contract that was carried out involved the construction of a new treated water rising main from Lough Forbes WTW to Prucklish, and the construction of storage reservoirs at Prucklish and Lisnannagh. Prior to this work being carried out, the existing rising main exhibited high headloss and leaks. The contract also increased the volume of water storage at Prucklish and Lisnannagh, in order to provide a secure water supply to the Longford Central area, including LongfordTown.
Following the completion of these works, the following positive impacts were realised:
- Significantly reduced pumping costs at Lough Forbes due to lower headloss in the rising main
- Significantly reduced leakage between Lough ForbesWTWand Prucklish Reservoir
- Use of durable materials for rising main, resulting in long design life
- EcIA was carried out for this project and found that the works would have no significant adverse impact on existing wildlife in the vicinity of Rinn RiverNHA
- Increased security of supply for central Co. Longford, including main economic hub of Longford Town.
- Provision of additional storage facilities was carried out in existing reservoir sites, without the need for increased land area
- Reuse of existing excavated material to form the embankments for the new reservoir tank