Integrated Constructed Wetlands

Irish Water is highlighting the benefits of nature based solutions to treat wastewater in small rural communities on the UN’s World Toilet Day which focuses on making sanitation a global development priority. The theme for World Toilet Day this year is ‘When Nature Calls’ and focuses on solutions that harness the power of ecosystems to help treat human waste before it returns to the environment. An example of such a solution are our operated constructed wetlands. We operate these facilities in two locations, Dunhill in Waterford and Clonaslee in Laois.

Integrated Constructed Wetlands are a type of nature-based wastewater treatment system that are designed to look and function as a natural wetland. Constructed wetlands are created for the purpose of treating wastewater in small rural communities in an environmentally-friendly way before allowing it to return to the water system safely.

Constructed wetlands are usually made up of a primary settlement tank where wastewater from the community is collected and from that, several ponds follow which are planted with wetland plants. The ponds are usually gently sloped towards a river to allow water to flow very slowly through the wetland before flowing away. Any particles that have been carried in the water will settle on the bottom and the plants and natural microorganisms (e.g. bacteria, algae and fungi) in the wetlands will break down and remove certain pollutants and elements e.g. phosphorus in the water. 

Rich in biodiversity and home to many species of flora and fauna 

Integrated constructed wetlands are carefully planned to integrate into the natural surrounding landscape and are built using natural materials like native plants, trees, soil, sand and stones. Both of these sites treat the wastewater from the communities in which they are located. They are also utilised by the community as recreational facilities. They are rich in biodiversity and are home to many species of flora and fauna such as ragged robin, flag iris, meadowtails, cattails and spreadwort which attract bees and butterflies that can help with pollination. Wildlife living on these sites, includes otters, frogs and newts. Clonaslee Integrated Constructed Wetland has featured on ECO EYE as the site is recognised as a shining example of green technology and an innovative way to treat wastewater.

Committed to sustainability in the way we treat wastewater

Speaking about Integrated Constructed Wetlands James O’Toole, Irish Water Engineer said “These sites demonstrate Irish Water’s commitment to sustainability in the way we treat wastewater. They are fantastic recreational resources for communities like Dunhill and Clonaslee to enjoy. These facilities enhance  biodiversity, protect the environment and are a sustainable solution for wastewater treatment in rural areas.  Integrated Constructed Wetlands form part of Irish Water’s sustainable model for wastewater treatment in Ireland.”

Irish Water is involved in a number of Integrated Constructed Wetland projects around the country. Dunhill in Co. Waterford, Glaslough in Co. Monaghan and Clonaslee in Co Laois, were already progressed prior to the formation of Irish Water, while a number of others are currently at design or planning stage including at Lixnaw in Co. Kerry and Saleen in Co. Cork. A further 11 sites are undergoing feasibility assessment at present.

Integrated Constructed Wetlands

For more information, visit our Wastewater Treatment in Wetlands section. 


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