Build-Over Agreement Drawings in Romford
Drainage drawings and survey information to support a Thames Water build-over application.
Drawings for the water company application
Building an extension or a new property over or close to a public sewer usually needs the water company's agreement first. We prepare the drainage drawings and survey information that go with a Thames Water build-over agreement application, so the people designing and building the project have what they need.
The supporting information can include existing and proposed drainage layouts and the findings of a CCTV drain survey of the pipes involved. Owners, builders and developers use it to understand what the drainage means for an extension, a new building or another construction project.
Applications and approvals stay with Thames Water and depend on its requirements and the circumstances of each project. We help with the drawings and information, and we cannot promise the outcome.
What's included
- Existing drainage drawings
- Proposed drainage layouts
- CCTV survey information for the pipes involved
- Supporting details for the application
- Drainage input for extensions and new buildings
Related photos



Building over or near a public sewer
Public sewers often run under gardens and driveways, and a planned extension can end up on top of one. The water company wants to know what is underneath and how the new building will affect it before it agrees, which is where good drawings and a survey of the existing pipes earn their keep.
We are based in Romford and prepare this information for projects across Romford, London and Essex. If a drain needs repairing or replacing before building starts, we can deal with that too.
What customers say
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The job was perfect, they were very good and friendly , excellent in time keepingJoseph U.Oct 2026
Excellent work from Jake and Ben. Any issues in the future will get in touch thanks a lot.. OmarSanzar I.Oct 2026
Great service from Jake! Highly recommendA M.Oct 2026
Amazing Service – Highly Recommended! I can’t thank the drainage team enough for their amazing work! I had a serious problem with my pipes, and everything was completely blocked. The team spent hours working hard to clear the blockage and sort out the problem. They were extremely professional, friendly, patient, and dedicated. Even though it was a difficult and time-consuming job, they didn’t give up and made sure everything was properly cleaned and working again. I was really impressed by their hard work, kindness, and positive attitude. They went above and beyond, and I truly appreciate all their effort. A massive thank you to the whole team! You are a credit to your company. I would highly recommend you to anyone who needs drainage services!Prisca N.Oct 2026
Phoned these guys that came out within two hours and got my mum‘s drains unblocked within 40 minutes. She’s always had a problem with this for a long time, it’s nice to deal with honest reliable people and at a very fair price definitely recommend this company, thank you again guys.Ray M.Oct 2026
Fully recommend to anyone with plumbing issues as they genuinely care to provide a good service and check up on the situation after. Had Jake over to check my loft bathroom and main bathroom on separate occasions and sorted out the problem ASAP and told us the next best steps to reduce costs in the long run. They encouraged us to go with the most cost effective option even if it was not benefitting them directly (in this case our newly done bathroom was having issues which came under a warranty).Ishaq U.Oct 2026
Highly recommend! Toilet was blocked they came out straight away. sorted quickly. Great price!Lucy B.Sep 2026
The team done a great job, I had 3 manholes to replace on my drive that were collapsing. They replaced with much better heavier duty ones.Jay N.Sep 2026
Not going to lie these guys actually know their stuff, not some shady guys that’ll give you the run around that your landlord knows… Anyway they came out on the day in an emergency and even went beyond to check the root of the issue! Will be coming back to them as they’re no nonsense. Also they said ETA was 1-2 and they made it here at one, don’t usually leave reviews but they definitely deserved oneS C.Sep 2026
My kitchen gully was Blocked. Called Essex drainage & construction and they unblocked it promptly within 1 hour. Very happy with their service, would definitely use again.Sangam G.Sep 2026
A very professional amazing job. This is the first time I have used this firm and I would highly recommend. Very polite and hard working individuals. The job was a difficult one but nothing was too much trouble, a very through job carried out, thankyou so much, would definitely recommend ⭐️Bernie M.Aug 2026
great company, really helped me out when I needed it most! couldn’t recommend enough 10/10 servicePeri S.Aug 2026
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Your questions about Build-Over Agreements & Drainage Drawings
Can't see your question? Call or message us and we will help.
What is a build-over agreement?
It is the water company's permission to build over or close to a public sewer. Thames Water applications usually come with drainage drawings and information about the pipes involved.
Do you submit the application for me?
We prepare the drawings and survey information that support an application. The decision stays with Thames Water and depends on the project.
Do I need a CCTV survey?
It often helps, because it shows the position and condition of the drains involved. We can survey the pipes and use the findings in the drawings.
Do you cover my area?
We are based in Romford and cover Romford, London and Essex. Thames Water serves much of London. Elsewhere in Essex another water company handles the sewers, so give us the address and we will confirm who to apply to.
Who do you work for?
Property owners, builders and developers, on domestic and commercial projects.
Related services

CCTV Drain Surveys
A camera inspection of underground drains to find exactly what is wrong.
View service
Drain Repairs
No-dig patching and lining, excavation repairs and pipe replacement.
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Sewage Treatment Plants
Treatment plants for properties without a practical mains sewer connection.
View serviceTell us about your drain problem
Send the details and we will call you back. If water or sewage is coming into the property, call 07871 537331 now.
- Call07871 537331
- WhatsApp07871 537331
- Email[email protected]
- Hours24 hours, 7 days
