Drainage and septic tanks
A septic tank sits close to a ditch and the survey did not measure the distance. Why is a binding-rules question for the papers, not a figure the survey guessed?
A binding-rules question belongs with the papers, not with a distance the survey guessed, because the survey did not measure how far the tank is from the ditch. The visit can say the tank sits close to the ditch. It cannot invent a clearance. Rules about where a tank may discharge, and how near a watercourse it may sit, are for the permits and the authority. The finding is unmeasured proximity. The survey has not produced a figure, and it should not be asked to pretend it did.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Binding rules for small sewage discharges are a regulatory scheme. They turn on facts the survey did not collect, including a measured distance and the nature of the discharge. Close to a ditch is a visual description. It might worry you enough to ask the question. It is not the measurement the rules use. Writing a guessed figure into the report would look like a survey result. It would be fiction. The survey stops at proximity without a tape.
The solicitor should ask for any permit, exemption or installer paper, and a specialist can measure if a number is genuinely required. Do not let a seller quote a distance the survey refused to invent. If the papers are silent, that silence is the problem to resolve. It is not resolved by going back to the report and pressing it for a figure it already declined to give.
What should you ask your surveyor?
- Did you describe the tank as close to the ditch without a measurement?
- Have you refused to invent a clearance?
- Which papers, rather than the survey, would hold a rules answer?
What are the typical next steps?
- Keep the note as unmeasured closeness to the ditch.
- Do not add a distance the survey did not take.
- Ask for the permit or installer papers through the solicitor.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
If the ditch is dry on the day, does that remove the rules question?
No. A dry ditch is still a ditch. The survey did not measure the gap, and dryness does not answer a binding-rules point. The papers, not the weather on inspection day, are where that question about the tank's position belongs.
Who holds the permit papers if nobody measured?
The owner should have them if they exist, and the solicitor should ask. The survey is not the permit file. Lack of a measurement is why the survey cannot answer the rules. It does not put the permit in the report.