Hafren Dyfrdwy (Severn Dee) Water Auxiliary Stormwater Tank

Summary

Project: Auxiliary Stormwater Tank,

Location: Trewern Sewage Treatment Works

Customers Name: Hafren Dyfrdwy Water

Hafren Dyfrdwy (HD), along with many other water companies, were seeking innovative solutions to increase the storage capacity of the Trewern Sewage Treatment Works facility and ease pressure on the system during excessive storm periods.

We met with members from different departments of HD water, as well as Brettex Site Services, at the Trewern site to discuss the requirements of the project and provide a tailored storage solution which will increase the capacity of the current system.

Challenges

Materials: Stormwater water runoff can be collected from multiple locations and often picks up pollutants prior to entering the drains. These pollutants can range from Motor oils, chemicals, animal waste and litter. Therefore, it was imperative that we manufactured the tank liners from a material capable of withstanding and storing, not only the stormwater, but the potential pollutants it may carry. Hence, we selected our Landflex® ES material, capable of storing petrochemicals and hydrocarbons unlike standard tank liners typically manufactured from EPDM.

Logistics: Sewage treatment works are often un-manned sites meaning there is not always someone available to accept a delivery. For this reason, we delivered the tank ourselves when travelling to Trewern for the installation.

Results

The tank materials were manufactured within 2-3 weeks from receipt of order, and we were able to deliver and install the tank within 2 days.

The tank consisted of one low level outlet, one mid-level outlet as well as two high-level inlets/ overflows each being 4-inch and terminating at PN16 flanges.

Another additional item to the tank was the reinforcing ring attached to the top edge of the tank. The reinforcing ring provides added rigidity and strength to open top tanks.

Overall, this tank will increase the current systems working capacity by 61m3 reducing the likelihood of overspills and thereby protecting the environment of our local rivers.

The client and their partners were satisfied with the complete end-to-end solution provided.