Sewer record maps

We have a duty under Section 199 Water Industry Act 1991 to maintain sewer record maps showing public sewers and lateral drains.

About our sewer record maps

Our public sewer maps record the location and position of sewers and drains in our region.

On occasion, we find historical errors and incorrect entries, which can be rectified with simple amendments, but correcting the status of a pipeline can introduce a change in ownership and responsibility.

We use Water UK's guidance to validate corrections to public sewer assets. We have also produced our own internal guidance.

We are not seeking widespread changes to sewer records. The most common reasons for reviewing them are reported flooding incidents, Surface Water Management Plans and flood risk planning.

Changes in ownership

If a change in ownership occurs, we will provide evidence to the affected landowners and statutory authorities before any changes are made.

Opportunities to validate, verify or raise objection will permit a collaborative approach.

Where we authenticate valid changes to sewer records, we will seek to agree any handover measures and transition periods.

These will vary according to the scale of the affected asset and relevant circumstances.

Transition periods

There are a number of options that may be considered over a transition period.

Firstly, handover arrangements will be agreed. This may involve sharing the following records:

  • record plans, drawings and GIS information
  • a list of scheduled maintenance activities (where required).

To assist with an orderly transfer, we may agree a transition period to secure resources, make funding arrangements and meet any identified needs.

Types of transition periods include:

  • immediate transition to a third party
  • Wessex Water funding maintenance for a defined period of one to two years – the Lead Local Flood Authority (LLFA) or Risk Management Authority (RMA) to allocate and apply resources within this period
  • Wessex Water continuing scheduled maintenance to clear debris and grids for a period, including emergency responses to flood events by the LLFA or RMA
  • Wessex Water retaining partnership maintenance obligations in the long term.