Graf UK urges architects to get their hands dirty

Wastewater treatment specialists Graf UK are calling on architects to help improve ground water quality throughout the UK. David Stagg, their technical product doyen, explains why.

We realise that asking architects to become more involved in wastewater treatment is a big one and they might not want to get their hands dirty but they are major influencers when it comes to the two factors that are driving this contentious issue.

One is that Natural England is increasingly “advising” local authorities to halt the determination of planning applications unless the developments can prove they will be nutrient (nitrogen and phosphate) neutral. High levels of these nutrients, which come partly from wastewater treatment discharges, cause excessive growth of green algae which smothers rare habitats and wildlife.

The other is an update to the General Binding Rules of January 2020. This is a bid by the Environment Agency to reduce the level of sewage pollution in the nation’s watercourses. Under the new rules, anyone with a septic tank discharging into a watercourse must replace it or upgrade the foul water solution.

SEPA (the Scottish Environment Protection Agency) requires wastewater treatment systems for up to 15 people to be registered on a public database so they know what system a property is running and where the effluent discharges to. A system catering for more than 15 people requires a licence and must meet a quality standard determined by SEPA so this can dictate the type of system installed. Here again, is where architects have an influence.

While architects are required to specify solutions for foul water drainage and disposal to Building Regulations Approved Document H, until such time as there is a national governing body for wastewater treatment monitoring, the Environment Agency, SEPA and NRW (Natural Resources Wales) are the individual organisations setting effluent quality standards.

These governing bodies have 100s of regional offices which generally operate independently, so are not set up the monitor this situation. In addition, approval for a sewage treatment plant is usually via a local authority’s building control department, but as all local authorities operate independently and already have large workloads, that’s an unlikely solution too.

As well as specifying a sewage treatment system that is appropriate for the level and regularity of use and the ground conditions, architects need to ensure it is installed, commissioned and maintained properly to avoid effluent issues down the line.

While the haphazard monitoring of sewage treatment, in England and Wales at least, looks set to continue for the foreseeable future, it has fallen to some manufacturers to become self-monitoring in themselves, working more closely with, and even training and providing technical back-up, to the specialist contractors who install, commission, service and maintain their systems.

This greatly reduces the potential for sewage treatment plants to develop issues which could affect local water quality, and if they do, for the issue to be nipped in the bud.