Useful definitions
Below we’ve given simple explanations for the terms you might find in your search report, together with extra useful information.
Adoption of sewers:
An adoption agreement transfers ownership and maintenance of the sewer to the sewerage undertaker. It’s then their obligation to carry out the improvements needed to meet increasingly stringent environmental standards.
Sewerage undertaker:
A limited company appointed by the Secretary of State to provide, maintain and improve a system of sewers and sewage treatment works.
Building over agreement:
As building over public sewers or water mains could cause damage and restrict access, no such building is permitted without a special agreement, known as a building over agreement.
Cesspool:
A sealed tank with no outlet used for storing sewage. They must be emptied regularly and the running costs can be substantial.
Combined sewer:
A sewer carrying foul water and surface water.
Conveyancing 29 form or CON29:
A standard form of conveyancing enquiry normally addressed to the local authority, published by the Solicitors’ Law Stationery Society Limited. The Conveyancing 29 form asks standard questions on such issues as planning, development, highways and smoke control orders. It also asks about drainage. Since 1989 sewerage undertakers have been responsible for maintaining records of public sewers.
Easements:
In this context an easement is a legal restriction on the activities landowners can undertake on and above an asset, such as a water main. In particular, tree planting and building are generally prohibited. Easements have been used when extra powers are deemed necessary by the water undertaker to protect the asset.
Foul sewer:
A sewer used to transport mainly foul sewage to a treatment works. It may also contain surface water from rainfall, when it may be termed a combined sewer.
Pre-1937 sewers:
The Public Health Act of 1936 set out a range of responsibilities for operating and maintaining sewerage systems, but recognised that little was known about existing sewers. Some had been maintained by private individuals and others by local authorities. Some of the costs had been recharged to the owners, and the location of all these early sewers had not been surveyed and was unknown. The Act acknowledged the different status of these early sewers and made provisions in respect of them.
Private drain:
A privately owned sewer draining only one property. If there’s no cesspool or private treatment works, the drain connects with a private or public sewer.
Private sewage treatment plant:
Generally a small sewage treatment works (which could be a septic tank) owned and operated by a community, hotel or household. These should conform to the same operational and environmental standards as the sewage works operated by the water companies. The running costs for small plants can be substantial, and as environmental standards are raised there may be a need for additional capital investment.
Private sewer:
A privately owned sewer draining more than one property. Connection to and use of such sewers normally requires private agreement. Rights of drainage or access, or easements to inspect, maintain, repair or replace the private sewer are usually required if the sewer passes through the adjoining land outside control of the property owner. All downstream sections must be properly maintained to avoid flooding with sewage.
Private water supplies:
Where a property has no connection to the water mains, a suitable private spring or surface water source may be used. This may require extensive treatment to make the supplies safe and will be subject to examination and control by the local environmental health officer. Approval under the Building Act 1984 for new building work to domestic properties will not be granted unless adequate water supplies and drainage facilities are available.
Public sewer:
A sewer vested in and maintained by the sewerage undertaker. Members of the public generally have the statutory right to connect into and use the public sewer on offering payment of sewerage charges.
Rising mains:
Pipes carrying untreated sewage pumped under pressure. There is no right of connection into them.
Section 102 declaration:
A sewerage undertaker may make, or may be asked to make, a declaration that sewers or sewage disposal works already in existence will be adopted and maintained at public expense from a particular date.
Section 104 agreement:
An agreement made under section 104 of the Water Industry Act 1991 between a housing developer and the sewerage undertaker for the adoption of sewers the developer intends to build in order to serve new houses. The agreement is often supported by a bond to guarantee proper performance.
Septic tank:
An unpowered settlement chamber for treating sewage and drainage waters. Overflow from the tank goes to a soak away, drainage field or occasionally a sewer. Houses with septic tanks are responsible for the operation, maintenance and occasional emptying of the chamber. Septic tanks function best in well-drained land, and it’s becoming less acceptable to operate a septic tank in low-lying land, particularly near rivers and streams. Septic tanks causing pollution may need to be decommissioned and the property connected to the public sewer.
Sludge main:
A pressurised pipe carrying treated or partially treated sewage sludge.
Soak away or drainage field:
Buried pipes are aggregates that allow treated effluents or surface water to disperse. They are owned and maintained by the property owner.
Surface water sewer:
A sewer used only for the transport of uncontaminated surface water or rainwater in an area where separate sewerage systems have been provided. This may discharge safely to a local watercourse or to the foul sewerage system for treatment with the foul flows.
Water Service Company:
A provider of sewerage and possibly water services in an area.
