From reed beds to cesspits, the ways to drain your waste

SEPTIC TANK

A tank buried in the garden that runs into an attached soakaway. Although traditionally the most popular option, new pollution rules mean such systems are no longer so common – though if you already use one it is not affected by recent legislation. If you need to repair or replace the tank in the future, you will have to invest in a large hygienic soakaway system that must be well maintained. The tank is often emptied once a year. Installation: From £5,000 Yearly cost: At least £100

AERATED SEWAGE TANK

Waste goes into a tank where it is aerated – with oxygen-breathing bacteria breaking down dirty sewage. Treated sewage then leads off into an irrigation soakaway. Alternatives include rotational machines as well as non-powered filtering systems. Often includes a blower and pump that works around the clock – using £50 of electricity a year. Prone to occasional breakdown so a regular service is often advisable – but it can cost hundreds of pounds. Installation: From £5,000 Yearly cost: At least £150

CESSPIT

A huge tank buried in the ground that collects sewage and dirty water waste. The only way it can escape is usually by being taken away by tanker. We each use on average 150 litres of water a day – so in theory a family of four could call out a tanker once a month to have it emptied. But old-fashioned cesspits were often built of brick so that waste naturally seeped out into the ground. Households with these can limit emptying to once a year. Installation: From £5,000 Yearly cost: Up to £1,000

REED BED

The common reed has the ability to transfer oxygen out through its roots if laid in a gravel bed, left. The plant can help digest pollutants in sewage. Often used as a secondary treatment for drainage coming out of a septic tank. Usually requires pumps and reed maintenance plus additional soakaway area. Installation: From £10,000 Yearly cost: Often £500