What are the ongoing costs of running a new sewage treatment plant?

There are three main running costs to factor in:

Electricity – the Graf sewage treatment plant is highly efficient. For an average domestic property, electricity consumption is less than that of a 60-watt lightbulb, equating to approximately £65 per year.

Emptying – the tank will need to be emptied on average every two to three years. You can arrange this with any approved tanker operator.

Annual servicing – under the General Binding Rules, sewage treatment plants must be serviced annually by a competent person. The cost is approximately £150 + VAT per year and will rise in line with inflation. WCI covers the cost of discharge monitoring for the first five years following installation under the scheme.