Commercial drainage surveys

Commercial drainage is rarely what the drawings say it is. Yards get resurfaced, units get subdivided, interceptors get bypassed, and surface water gets connected into foul by somebody in a hurry twenty years ago. By the time it matters, nobody has a current record.

A drainage survey underway on a commercial site

We survey it, grade it and map it — the same day.

Call 0800 772 33 99 · Discuss a site

Who this is for

Managing agents and landlords — condition reporting across a portfolio, and evidence at the point where a tenant leaves.

Facilities and site managers — planned maintenance instead of emergency call-outs, and a record of where the system actually runs.

Building surveyors — drainage evidence to attach to a schedule of condition or a building survey, coded to a standard a third party will accept.

Developers and contractors — pre-adoption and as-built surveys, and the evidence pack for a build over agreement or a section 185 diversion. See build over agreements and sewer diversions.

What we survey

  • Yard and service road drainage, including gullies, channels and catchpits
  • Interceptors, petrol interceptors and grease traps — condition and whether they are actually doing anything
  • Foul and surface water runs, with the two properly distinguished, which they frequently are not on site
  • Roof drainage and downpipe connections
  • Larger diameter runs beyond domestic scale
  • Car parks, loading areas and hardstanding, where access is through covers under live traffic

Schedules of condition and dilapidations

At the start and end of a lease, drainage is one of the few building elements that cannot be inspected by looking at it. A coded, graded survey with a site plan gives both parties something specific to argue from rather than an assertion.

Taken at the start of a term, it is the cheapest insurance a tenant can buy. Taken at the end, it is what a landlord needs in order to substantiate a claim.

Planned maintenance rather than emergencies

For premises with grease traps, interceptors or a history of surcharging, scheduled jetting is straightforwardly cheaper than reactive call-outs — and a great deal cheaper than a day’s lost trading. We can survey first, establish what the actual risk is, and set an interval that reflects it rather than a generic one.

High-pressure drain jetting

What you get

MSCC-coded observations positioned in metres, a Drain Repair Book grade for every section, a site plan of the system, and the full video. Reporting the same day, by NADC-certified surveyors, with the certification number on the report.

We do not carry out drain repairs, relining or excavation. For a commercial client that is usually the point: the survey is evidence, not a sales document, and whoever tenders for remedial work is doing so against a report with no interest in the outcome.

Common questions

Can you work out of hours or around trading? Access arrangements are usually the constraint on a commercial site rather than the survey itself. Tell us the constraint and we will work to it.

Do you carry the right insurance and accreditation? Yes — surveys are by NADC-certified surveyors and every report carries the certification number. Insurance details are available on request.

Can you survey a live system? Usually, though flow affects what the camera can see. For larger runs we would discuss controlling flow beforehand.

Can you produce a report our surveyor can append to theirs? That is what the MSCC coding and the DRB grading are for — it is written to be read by a third party.

How large a site can you handle? We have surveyed systems of thirteen separate runs in a single visit. Tell us the scale and we will tell you honestly whether it is a job for us.


Talk to the person who will do the work.

0800 772 33 99

Request a call back

Surveys across the West Midlands, south Staffordshire, east Shropshire and north Worcestershire. Unblocking closer to home.

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