Due to the age of the sewerage network, there is an increasing need to carry out “rehabilitation” (repair and maintenance work) to ensure optimum service is delivered to customers. As part of the ongoing commitment to improving services to customers, NI Water has a long-term programme for the improvement of the existing sewerage network.

NI Water have an ongoing programme to undertake CCTV surveys of existing sewers to identify and prioritise parts of the sewerage system that require rehabilitation. We continually undertake repair and renovation of existing sewers, and replace sewers that collapse or are otherwise beyond their useful lifespan. Works on this major project are currently being delivered through a number of contracting partners, at various locations throughout Northern Ireland.

What will the work entail?

The work may involve the relaying, relining or repair of existing sewers. Wherever possible the work will be undertaken using specialist “no-dig” or “low-dig” methods, which minimise the amount of ‘open’ excavation required. This is to minimise disruption to the public, businesses and road users as much as possible. However, where these methods are not possible, work will be carried out by “traditional” open trench methods.

At some locations, the work may involve lane/road closures, which will be agreed with the Department of Infrastructure in advance. All appropriate signage will be in place to inform the public, and we will work closely with our contracting partners to ensure disruption is minimised as far as possible.

On occasions, due to the location and nature of the works it may be necessary to carry them out during the evening/night time hours. This may be to allow the works to be undertaken safely, protecting the safety of road users, the public and construction workers, or to reduce the impact on road users/businesses.

What benefits do these works provide?

When work is completed in a specific area, it will: -

• Improve the condition of the system
• Reduce the likelihood of sewer collapses and blockages
• Reduce the associated likelihood of out-of-sewer flooding 
• Reduce long term disruption to customers and road users as a result of ongoing maintenance
• Reduce long term maintenance costs

NI Water fully realises that work of this nature can be unavoidably disruptive, more so at some locations than others, particularly where temporary road closures and traffic diversions are required. In partnership with our Project Managers AECOM, contractors Geda Construction, we will work closely with the Department for Infrastructure and other key stakeholders to minimise inconvenience and disruption to local residents, businesses and road users as far as practicably possible.

In addition to the planned work programme, NI Water also have an ongoing programme of unplanned sewer rehabilitation works. This entails more reactionary type works, which are often emergency in nature and are also carried out throughout Northern Ireland. Due to the nature of these works, there may be a limited amount of notice for the public as they are often undertaken to prevent a sewer collapse or property flooding.

 

Existing sewer requiring emergency repair

Bag it and Bin it – Help us look after the upgraded sewers!

NI Water spends approximately £2.5 million a year on clearing blocked sewers. We would like to ask for the public’s assistance in reducing these by not placing inappropriate items in the toilet, down a drain or into the sewers.

Find out more at   https://www.niwater.com/bag-it-and-bin-it/

 

Following acceptance that agreement could not be reached for NI Water’s proposals for the solution involving access to Balmoral Golf Club land, the whole project had to be reconsidered to devise an alternative solution for the Sicily and Marguerite Park areas that would not increase flood risk elsewhere.

It has become clear that in order to address the flooding of Sicily Park, an extension of the Belfast Stormwater Tunnel is required. At present Phase 2 (including the tunnel extension) cannot proceed without funding the Living With Water Programme. Therefore, at this stage, it is only feasible to address flooding in the Marguerite Park area. Consequently, the project will now be split into two phases as illustrated in the map below.
Phase 1 will address flood risk in the Marguerite Park area, and will involve laying new, large diameter sewers between Musgrave Park and the Lisburn Road (Marguerite Park area). We anticipate construction will commence in early 2021 and take 18-24 months to complete.

Phase 2 will address flood risk in the Sicily Park area. The timing of this phase depends on completion of the (separate) project to extend the Belfast Stormwater Tunnel to Musgrave Park. Funding for Phase 2, and the tunnel extension project, will be applied for in NI Water’s ‘Living With Water Programme’* funding requirement, which will be submitted to the NI Utility Regulator at the same time as our ‘PC21’ funding requirement.**

Other Improvements
NI Water, in partnership with DfI Roads, will undertake road drainage improvements in the vicinity of the Sicily/Locksley Park junction during Phase 1. In combination with previously completed drainage infrastructure improvements in the area, this work will help further reduce flood risk in the Sicily Park area until Phase 2 is completed.

Project Development
Project development for all phases is ongoing, however, we appreciate it is taking more time than anticipated. This is a major infrastructure project, with many complexities. As we had to reconsider the project solution and design, we had to change our plans and tailor site investigations for the detailed design work accordingly. As part of this, extensive analysis of all of the existing drainage networks in the area was also necessary.

Results from initial investigations have also revealed information that requires further investigations to address certain engineering challenges. Whilst more time consuming, it is important that we address these challenges to reach final designs, which, as far as possible, will minimise constructional risks and disruption to all those who will be affected.

NI Water appreciates the development of this project has taken considerable time and understands the frustration of local residents impacted by flooding and we are thankful for their considerable patience.

Our operational staff, along with the other statutory agencies, will continue to monitor the area closely during periods of heavy rainfall to mitigate the effects of flooding.


* Living With Water Programme - A multi-agency initiative headed by the Department for Infrastructure to develop a Strategic Drainage Infrastructure Plan (SDIP) for Belfast to support economic growth, protect the environment and address flood risk.
** PC21 funding requirement – NI Water Capital Works Funding Programme, which covers the period 2021-2027.
 

NI Water are due to undertake a £4m programme of work to replace ageing wastewater pumping stations at Brompton Road and Stricklands Glen as part of the latest phase of a wider multi-million-pound investment to improve water quality along the North Down coast.

Stricklands Glen Pumping Station 

The scheme, which is due to get underway in full in early April, will also involve the upgrade of the associated sewerage network to help prevent out-of-sewer flooding in the future.

For further details click on the links below:

Background

The Benone Vacuum Sewerage System was installed in the early 1990s. Consisting of 60 valve chambers and 6,000m of sewers, the system serves local caravan parks, tourist amenities and a small number of private houses. In addition, flows from the Downhill area are also pumped to the Benone vacuum system. It was originally designed to cope with a summer population equivalent (PE) of 2,250 and a winter PE of 120, but figures show that in recent summer months the population equivalent in the area has increased to more than 3,300. The increase in visitors to the Benone area during peak tourist seasons, coupled with unseasonal heavy rainfall, mean that on occasions the existing system struggles to cope with the pressures being exerted on it, resulting in a high level of call outs from NI Water.

Need for upgrade

Vacuum sewerage systems consist of sealed structures designed only to transfer sewage to either a wastewater pumping station or a treatment works, and are not intended to convey storm (surface) water. If, during heavy rainfall, the system becomes overwhelmed – due to infiltration – it can lead to a loss of vacuum and result in localised out-of-sewer flooding.

To address the problem, NI Water undertook an appraisal of the existing Benone vacuum system and work is well underway to complete a £2.1m programme of work to enhance the performance of the network to meet present and future needs.

NI Water and its design team developed a solution that optimises the performance of the network with minimal impact on local amenities.

The solution involves replacing the majority of the existing valve chambers with conventional sewers and the introduction of new wastewater pumping stations (WwPS) which will reduce the hydraulic loading on the network. The small section of the vacuum system being retained along the Seacoast Road and in part of one caravan park will be enhanced to improve reliability and accessibility.

A total of 5 new WwPS will be constructed at strategic locations in the network:  Benone Tourist Complex; Benone Avenue North and Benone One Transfer have now been completed, with work on schedule to complete Golden Sands and Benone Avenue South Pumping Stations by Easter 2021.

New pumping mains and sewers will be included in the scheme to allow these new pumping stations to connect to a new terminal pumping station adjacent to the Benone vacuum station; which in turn will utilise the existing twin pumping mains to transfer flows to Aughil WwPS and on to the new wastewater treatment works at Magilligan.

Benefits of the scheme

Once complete, this major scheme will provide a more robust sewerage network, capable of coping with an increased number of tourists to caravan parks and local amenity areas in Benone.

The introduction of conventional wastewater pumping stations will reduce the likelihood of out-of-sewer flooding and provide a more reliable system that will require less operational maintenance.

NI Water and our project team appreciate the support of local landowners and other stakeholders in developing a suitable, cost-effective solution that meets the needs of a wide section of the tourism industry in Benone. We would like to thank the local community for their patience as we complete this essential project.