Operating and maintaining your sewage treatment plant

Operation

a) Sewage treatment is an ongoing process and the micro-organisms must stay healthy for the system to work. You should de-sludge the system regularly to prevent the build up of sludge and solids so that sewage flows freely through the unit. You should check that anyone you use to remove sludge from the system is registered with the environmental Agency to carry waste. This may be the local sewer provider or a private contractor. Sludge should normally be removed every 12 months or in accordance with the manufacturer’s instructions.

b) Sewage treatment plants use biological treatment that requires a stable environment to work well. You should check that the plant is protected against substances that might damage it and kill the micro-organisms. Check with the manufacturer’s instructions on the use of cleaning materials, such as bleach. Do not use the connecting drains to dispose of chemicals, oils, solvents, grease or paintbrush cleaning fluids.

c) No clean uncontaminated roof or surface water should enter the sewage treatment system. This may be a legal requirement. This can reduce the system’s capacity and can cause solids to be flushed out which may cause pollution and flooding.

d) You must make sure that when the system is installed, a notice is fixed within the building describing the maintenance needed for your sewage treatment plant. This will help subsequent occupants of the property and ensure that the system continues to be maintained effectively. The notice should detail the treatment system’s size, type and location along with details and frequency of the required maintenance operations.

Property Volume per person or activity Property Volume per person or activity

(litres per day) (litres per day)

Domestic 200 Offices 50 (without a canteen)

Hotels 300 per guest Factories 50 (without a canteen)

Restaurants 30 if full meal luxury catering Public Houses 12 per customer

Campsites 75 Caravans 100 if non serviced touring

Day school 50 (without a canteen) Rest Homes 350

Boarding school 200 per resident Hospitals 450

e) If the site changes ownership, the manufacturer’s instructions and any consent to discharge for the system should be transferred to the new owners.

f) You must make sure there is adequate vehicular access to empty and maintain your system.

Maintenance

Use operators experienced in dealing with sewage treatment plants to carry out the maintenance identified in the manufacturer’s instructions. The manufacturer of your system should be able to provide you with the details of an appropriate company. We recommend that you enter into a maintenance agreement with a suitable contractor. British Water have established a service training scheme for accreditation of engineers and details of accredited engineers can be found on their website.

a) If the system requires a power supply, it must be available with no breaks in supply, as this can lead to the death of the micro-organisms. We recommend you fit an alarm to warn you of any electrical failure.

b) If the system discharges to a watercourse, the outfall should be inspected monthly to check effluent quality. If you notice any deterioration, maintenance contractors should be called out to assess the performance of the unit right away. Deterioration of effluent quality is indicated by the development of grey slime on the bed of the stream, bad smells coming from the stream or an obvious difference in the plant life downstream of the discharge point.

Bio Pure
Marsh
Bio Disk
Conder
Modular

Why Package sewage treatment plants?