Are temporary wastewater treatment plants the key to facilitating development in Ireland?
In Ireland, where housing needs are at their highest ever, with almost 15,000 people without a home, much-needed housing developments are being postponed due to a lack of investment in wastewater infrastructure.
There are sites and developers all over the country with projects on hold as local municipal wastewater treatment plants wait to be upgraded to the required standard. These projects are being evaluated individually and prioritised where the largest populations are located. This leaves small towns and villages questioning their future, with many families living in hotels.
The Irish Examiner published an article on the 5th of August 2024 discussing the town of Dunmanway in Co.Cork, where development of any type needing a connection to the main sewer won’t be permitted until the necessary municipal treatment plant upgrades are in place despite saying the town needs at least 126 new homes to cope with the population growth by 2028.
Temporary or containerised wastewater treatment plants may offer a solution to the developers, but the local authorities are slow to adopt temporary wastewater treatment plants as they are still dealing with the effects of the construction crash in 2008, where they were left responsible for servicing and maintaining treatment plants all over the country.
The benefit of a temporary wastewater treatment plant is it can treat the sewage to a pre-determined standard on-site and only allow the treated effluent to discharge to the main sewer, therefore reducing the organic loading the existing municipal treatment plant has to deal with.
It is also possible to discharge to groundwater using a percolation area depending on the hydraulic loading, space available, and ground conditions on the proposed site. This presents opportunities and removes one of the many barriers preventing housing and infrastructure development.
Over the last few years in Midleton in Co.Cork, Cork County Council has carried out works on the storm network to reduce the stormwater entering the municipal wastewater treatment plant, which, alongside temporary plants, created additional capacity and facilitated new large housing developments that previously wouldn’t have been possible.
It’s this collaborative thinking and shared vision that needs to be rolled out across the country to promote development in small towns and rural areas.
Temporary wastewater treatment plants are generally more flexible and fall into two categories: traditional wastewater treatment plants where they are buried in a suitable location or above-ground containerised systems. Both can be used on a long-term basis, but if a temporary wastewater treatment plant is the right solution for your project, the timeline plays a crucial role in the decision-making process.
For example, if you intend to use the treatment plant for 6-12 months, then containerised systems are more cost-effective because they are easy to install, suitable for use on other projects, and can be moved relatively quickly. They are plug-and-play and can be extended on a modular basis if the population equivalent changes. However, if the system is going to be in place for several years, a traditional wastewater treatment plant could be more practical in site-specific circumstances.
The biggest difference between a below-ground and above-ground installation is the requirement to pump the raw sewage to the wastewater treatment plant. Some projects can achieve a gravity flow while others have to be pumped, meaning an above-ground treatment plant cannot take advantage of this. Decommissioning and moving traditional wastewater treatment plants can be more challenging and time-consuming with the additional labour costs involved, but by utilising an SBR process, you can expect to see the same treatment standards with both alternatives.
According to another article written by Sean Murray in the Irish Examiner, housing and commercial development are not the only considerations: “wastewater treatment in many areas is not good enough to prevent wastewater discharges from impacting rivers, estuaries, lakes and coastal waters, and according to Uisce Éireann's estimates, it could take over 20 years to meet the required standards.”
To address whether temporary wastewater treatment plants are the key to facilitating development and protecting our environment, we must consider whether we can wait for centralised wastewater infrastructure to catch up or take proactive steps to solve the problem ourselves.
Temporary systems have already demonstrated their potential to create growth opportunities, but their broader adoption requires collaboration between developers, local authorities, and policymakers to ensure sustainable progress.
