Trade effluent consent or an environmental permit

Where the effluent goes decides which consent you need. Discharge trade effluent to a public foul sewer and you need a trade effluent consent from the sewerage undertaker under section 118 of the Water Industry Act 1991. Discharge to a surface watercourse or to groundwater and you need an environmental permit from the Environment Agency under the Environmental Permitting (England and Wales) Regulations 2016. Neither is a planning consent, and a planning permission grants you neither.

Plenty of fit-out programmes assume the planning permission settled the drainage. It did not, and the two consents have different applications, different timescales and very different charging regimes.

Discharge to sewer and who consents

Trade effluent is liquid waste from a trade or industrial process, which in practice covers far more than factories: commercial kitchens, car washes, laundries, laboratories, dental practices, food production and brewing all generate it.

The route is a notice of the proposed discharge to the sewerage undertaker, which may then give consent with conditions. Those conditions typically cover the maximum volume and rate of discharge, the composition and temperature limits, the discharge point, pre-treatment such as grease interception or pH correction, and sampling access.

Discharging trade effluent to a public sewer without consent is an offence. That point deserves emphasis because the operator of a new kitchen or workshop frequently does not know the consent exists as a requirement.

If the undertaker does not give consent within the statutory period following the notice, or imposes conditions the applicant objects to, there is an appeal route to the water services regulator. Check the current procedure, because the practical answer is usually negotiation with the undertaker rather than an appeal.

Discharge to a watercourse and who permits

A discharge to inland freshwater, coastal water or groundwater is a water discharge activity or a groundwater activity under the 2016 Regulations, and it needs a permit from the Environment Agency unless an exemption or a set of general binding rules applies.

Small domestic sewage discharges are the familiar exemption, subject to general binding rules on the type of treatment, the location and the volume. Trade effluent discharges are rarely exempt.

The permit application asks about the receiving water: its quality, its flow, the effect of the discharge on it, and the monitoring the operator will carry out. Standard rules permits exist for some common activities and are determined faster. A bespoke permit, where the discharge or the receiving water does not fit a standard set, takes longer and costs more.

What each application asks for

For a trade effluent consent, assemble a process description, the expected volume and discharge pattern, an effluent characterisation covering chemical oxygen demand, suspended solids, pH, temperature, fats, oils and greases and any specific substances, a site drainage plan distinguishing foul from surface water, and details of any pre-treatment.

For an environmental permit, assemble the effluent quality and volume, the discharge point with coordinates, a description of the receiving water, an assessment of the effect on water quality against the relevant standards, the treatment process and its reliability, and the proposed monitoring.

In both cases the drainage plan is the document that gets scrutinised first, and in both cases a site where foul and surface water have been cross-connected for thirty years produces an awkward conversation. Survey the existing drainage before you apply.

Monitoring and charging arrangements

Trade effluent charges are calculated on a volumetric formula that reflects the volume discharged and the strength of the effluent, measured through chemical oxygen demand and suspended solids, together with the cost of treatment and sludge disposal. The practical consequence is that reducing the strength of the effluent, through screening, grease interception or settlement, reduces the bill as well as improving compliance.

Permit holders pay an application fee and an annual subsistence charge, and carry their own monitoring obligations with results reported to the Agency.

Budget for both the capital cost of pre-treatment and the ongoing charge. A business plan built without the discharge charge in it is usually out by a meaningful amount on a wet process.

Where planning conditions overlap

Planning conditions reach into this territory without granting either consent.

A permission may require a foul and surface water drainage strategy to be approved before works start, evidence of capacity from the undertaker, the provision of grease interception, pollution prevention measures during construction, or a condition preventing occupation until drainage works are complete.

Those conditions are discharged with the authority, not with the undertaker or the Agency, and they are satisfied by documents rather than by the consent itself. A Foul Sewage Assessment is usually the document that addresses capacity and the method of disposal, and a Drainage Strategy deals with surface water, attenuation and outfalls. Where water supply is also constrained, a Water Supply Assessment covers the other half of the picture.

The sequencing argument is the same one that applies when choosing between a Basement Impact Assessment or a Flood Risk Assessment: establish which regime governs before commissioning the report.

Timescales against a fit-out programme

The planning permission is often the fastest of the three.

Allow a realistic period for a trade effluent consent, including time for the undertaker to ask for effluent sampling you have not yet generated, which is the classic problem for a new process. Allow longer for a bespoke environmental permit, and longer again if the receiving water is already under pressure.

Then allow time for the physical works. A grease management system, a balancing tank or a settlement stage all need space, access and power, and retrofitting them into a completed fit-out is where the money goes.

One sequencing tip that saves whole months. Ask the undertaker for a pre-application discussion before the lease is signed, with the process description and the expected effluent strength in hand. The capacity position at the receiving treatment works is something only they know, and a site served by a sewer that is already at its consented load will get a consent with tighter conditions and a larger pre-treatment requirement than the same process two streets away.

The equivalent step for a watercourse discharge is to ask the Environment Agency about the status of the receiving water body. Where it is already failing against a quality standard, the permit conditions will be tighter and the assessment required with the application will be longer.

Deciding which consent applies

Four questions settle it.

Where does the effluent physically go: a public sewer, a watercourse, groundwater, or a private treatment plant with its own discharge. Is the liquid trade effluent, or domestic sewage, or clean surface water. Is there an exemption or a set of general binding rules that covers it. And does the existing drainage actually do what the record plan says it does.

If the answer to the last question is unknown, commission a drainage survey first. Every other decision depends on it.

To see which drainage and water documents a scheme is likely to need, browse all 66 PlanScope report types.

This is general guidance, not legal advice; check the position with your local planning authority, the sewerage undertaker, the Environment Agency or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.