GPS drainage mapping surveys for London properties. You get an accurate plan of pipe routes, invert levels, flow directions and manhole positions. Plans like this help with extensions, build-over applications and estate drainage records.
A drainage mapping survey joins a CCTV camera inspection to GPS positioning. The result is an accurate plan of your drains. It shows where each pipe runs, which way it flows and the invert level at each manhole. It also shows how your private drains meet the public sewer.
In London, a plan like this matters for any extension or basement near a drain run. Thames Water needs evidence that the work will not harm the public sewer. Many older properties have no drain records at all, because Victorian pipes were never formally mapped. A survey is often the only way to learn the layout before design work starts.
Managing agents and freeholders also ask for mapping surveys. Blocks of flats, HMOs and converted Victorian terraces often dispute who owns shared drains. A single survey by a neutral party gives everyone one record to rely on. As a result, a dispute that could run for months through solicitors can end soon after the report arrives.
We supply plans in a clear format for architects, structural engineers, Thames Water and local planning authorities.
Good plans save time on later work. Since designers know where the pipes run, they can avoid costly clashes. Contractors, meanwhile, can dig with confidence. The plan stays useful for repairs, sales and future building projects.
Prices vary because every job differs. Mapping survey prices for homes depend on the complexity of the network, the number of manholes and the detail you need in the plan. We quote commercial and estate surveys one by one. Request a quote online.
Yes. Thames Water asks for a pre-build CCTV survey that shows the condition of the public sewer. This applies to any extension or structure within 3 metres of an adopted sewer. A mapping survey gives you that evidence. It also gives you a plan that shows the sewer position next to your planned structure.
Often it can. A mapping survey plus a Thames Water drainage search shows which pipes you own and which belong to Thames Water. This matters most in converted Victorian terraces and blocks of flats, because ownership there is often unclear.
A standard home survey takes one to three hours on site, depending on the network. The plan follows the survey. Complex estates and commercial sites with many manhole runs need longer for the finished plan.
While you plan the work, read our guide Thames Water vs. Homeowner: Who Is Responsible for Your London Drain?. It covers what to check before you ask for a quote.