PurewaterEnvironmental

A septic tank simply separates solids from liquid and relies on the ground to treat what's discharged, so it can only ever discharge to a drainage field. A Purewater sewage treatment plant actively treats the effluent using aeration, producing a clean, oxygenated discharge that meets the standard needed to go to a watercourse or ditch, as well as to a drainage field. If you don't have suitable land for a soakaway, a treatment plant is usually the only compliant option.

Sizing is based on population, not property size — Purewater plants are rated by population equivalent (PE), typically covering anywhere from a single dwelling up to larger commercial loadings. As a rule of thumb, work out the maximum number of bedrooms/occupants and select a model rated at or above that figure, since undersizing leads to poor treatment and higher running costs. If you're between sizes or serving a mixed-use site, it's worth getting the loading confirmed before you order.

Yes — installation of a sewage treatment plant falls under Building Regulations (Part H), so your installer or building control body needs to sign it off. If the treated effluent discharges to a watercourse rather than a drainage field, you'll also need to register or apply for a permit with the Environment Agency (or NRW in Wales) before it goes live. Discharges to ground via a drainage field are generally exempt but still need to meet the General Binding Rules.

Yes, but the tank needs to be specified and installed correctly to resist flotation — this usually means anti-flotation collars, a suitably sized concrete base and, in some cases, ground anchoring straps. Your installer should carry out a site survey and check ground conditions before installation, as getting this wrong risks the tank lifting out of the ground once backfilled. Always flag a known high water table when ordering so the correct kit is supplied.

Purewater plants need an annual service by a competent engineer to check the air blower, diffusers and general operation, plus periodic desludging — typically every 6 to 12 months depending on usage and tank size. Regular servicing keeps the plant working within its permit conditions and avoids costly failures, and most manufacturers require proof of servicing to keep the warranty valid. Budget for this ongoing cost alongside the initial purchase.

Plants are usually delivered on a kerbside pallet or crane-offload lorry, so you'll need clear site access and someone available to take delivery — these units are large and not something one person can move by hand. Installation involves excavation, a concrete or as-specified base, correct backfill (often pea shingle for GRP tanks), electrical connection for the blower, and final commissioning. It's a job for a competent groundworker or specialist installer rather than a DIY weekend project.