Three separate systems, three different standards, three different adoption routes. We help developers plan and deliver all three correctly from the outset.
Clean water, foul drainage, and surface water are three completely separate infrastructure systems. Here is what you need to know about each one.
Clean (potable) water is delivered from the water treatment works via the water company's pressurised distribution network. New water mains for residential and commercial developments are installed by a WIRS-accredited Self-Lay Organisation (SLO) such as USP, working under a self-lay agreement with the water company. All materials must be WRAS approved. The water main is pressure tested, chlorinated, and bacteriologically sampled before the water company formally adopts it. This is the system that supplies drinking water, bathroom, and kitchen supplies to each plot.
Foul drainage collects wastewater from toilets, sinks, baths, and showers and conveys it by gravity to the public sewer network. New foul sewers for residential developments must be designed to the Sewers for Adoption 7th Edition (SfA7) specification and adopted under a Section 104 agreement. The system is gravity fed, with pipes laid to consistent gradients, and requires CCTV survey on completion before the maintenance period begins. The foul sewer is entirely separate from the surface water system, and the two must never be connected.
Surface water drainage collects rainfall run-off from roofs, roads, and hard standings and conveys it to a suitable discharge point, such as a watercourse, soakaway, or public surface water sewer. In many areas, Sustainable Drainage Systems (SuDS) are required by planning policy to attenuate run-off and reduce flood risk. SuDS features may include permeable paving, swales, basins, and ponds. The adoption route for surface water infrastructure varies and may involve the Lead Local Flood Authority (LLFA), a management company, or the water company if a public surface water sewer exists.
All three systems must be planned independently from the earliest stage of the development programme. Each has its own design standard, approval authority, adoption route, and timeline. The clean water self-lay agreement and the Section 104 foul drainage agreement both need to be in place before connections to the public network can be made. SuDS approval may need to be discharged as a planning condition before any drainage work begins. A common source of programme delay is discovering late in the build that one system has not been approved, designed, or sequenced correctly. USP advises on all three systems at inception.
The critical parameters that distinguish clean water, foul drainage, and surface water infrastructure.
Multi-system water infrastructure expertise from a single WIRS-accredited provider.
Every water infrastructure project we deliver meets the highest industry standards. Worker safety, public safety, environmental responsibility, and project compliance from planning to sign-off.
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I contacted USP and within minutes had a chat with Justin who described exactly how the job would be done and provided a comprehensive quote including labour and materials and was able to start the work in just 7 days. Justin and his team were brilliant and did an amazing job. I can highly recommend USP.
Jack and Joel were absolutely amazing this morning and really put themselves out to dig a hole without having to dig another hole in my drive. More work for them but one happy customer.
From the initial quote through to work completion, Justin and his work partner were a mix of professional, knowledgeable, good-humoured, and clear in all explained (I felt an instant ease to agree to the work). The work itself was excellent and they left the place immaculate!
George and Jack come out today to move a gas meter. It wasn't a straightforward job, but they both took time to talk me through what they were doing and what the next steps are. Very friendly and polite and thought about the needs of our family.
Jack and George are great.
Bang on time, completed the work perfectly, no issues. Left the meter really neatly finished. Jack and Joel were very courteous and did a great job.
George and Jack turned up and did a first class job, very friendly and professional. Great job lads.
Jack and Joel were brilliant. Very polite, worked to my highest expectations. Left the area as clean and tidy, as was possible. And explained every step of the process to me, answering any questions I had.
Fantastic work from Jack and Johl.
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