Commercial Drainage Service
Drainage Investigations
For the problems that clearance does not solve: recurring blockages, unexplained flooding, persistent odour and systems nobody has an accurate record of. An investigation finds the cause before money is committed to a remedy.
Some drainage problems are obvious. A blockage clears, the run flows, and that is the end of it. Others come back — a yard that floods every winter, a smell in a tenanted unit that nobody can place, a run that blocks three times a year despite being jetted, or water appearing where there is no drainage shown on any plan.
Those are investigation problems, not clearance problems. Attending them reactively can go on indefinitely, because each attendance addresses the symptom in front of it rather than the reason it keeps occurring. An investigation works across the system instead of a single run, and finishes with a cause and a recommendation.
The drainage professional behind The Drain Lads has over 20 years of experience in the drainage industry. Investigative work is where that counts most: knowing what the pattern of a problem is telling you, which runs to check in what order, and when the evidence is genuinely conclusive rather than merely suggestive.
When this service is used
Blockages that keep coming back
The same run failing repeatedly, or several runs on one site failing in sequence, usually indicates a defect, a capacity issue or a use problem rather than bad luck.
Flooding with no obvious cause
Yards, car parks, basements, service areas or landscaped areas that surcharge in rainfall the system should comfortably handle.
Persistent odour in occupied buildings
Smells in offices, retail units, care settings and washrooms that cleaning does not resolve — often a dry trap, a defective connection, a redundant run or a broken stack.
Suspected misconnections
Foul discharging into surface water, or surface water into foul. These cause pollution issues, water authority involvement and capacity problems, and are common on altered or extended buildings.
Unknown drainage layouts
Older industrial sites, buildings that have been extended, and multi-tenant properties where nobody holds an accurate record of the chambers, runs and connections that exist.
Disputes and insurance claims
Where the cause and location of a fault determine who is liable for it, and where an evidenced conclusion is needed rather than an opinion.
What an investigation typically establishes
The outcome is a cause with evidence behind it, plus a clear position on what should be done about it and in what order.
- Which specific defect, run or connection is producing the recurring symptom
- Whether the system is defective, undersized for how the property is now used, or simply neglected
- Where foul and surface water are wrongly connected, and what that is causing downstream
- How the site actually drains, including chambers, runs and connections missing from existing plans
- Whether the problem originates on your property, on an adjoining property, or in the public sewer
- Whether a previous repair or alteration has created the problem being investigated
- Whether use — grease, wipes, process waste, site debris — is a contributing factor that maintenance can address
- What needs to be done now, what can be planned, and what only needs monitoring
Process
How an investigation is carried out
An investigation is a sequence, not a single visit. Each stage narrows the possibilities so the next one is targeted.
- Step 1
History and symptoms
We start with what has happened: when the problem occurs, what it affects, what has been done about it before, and any plans, survey reports or maintenance records that exist. The pattern usually narrows the field considerably.
- Step 2
Site inspection and tracing
Chambers are located and lifted, the layout is established and, where the system is undocumented, runs are traced and mapped so the investigation is working from what is actually in the ground.
- Step 3
Survey and testing
Relevant runs are cleaned as needed and surveyed by camera, with connectivity checks used where connections or misconnections are in question.
- Step 4
Findings and recommendation
You receive the cause, the evidence for it, and a proportionate recommendation — separating the work that resolves the problem from work that is desirable but not the reason you called.
Why investigation matters for commercial premises
Recurring drainage problems are rarely accounted for accurately. The visible cost is the attendance invoice; the real cost includes the trading time lost, the staff time absorbed, the tenant complaints, and the eventual failure that occurs when the underlying defect finally gives way.
Investigating first also protects the drainage budget in the other direction. It is common for an investigation to show that a proposed excavation is unnecessary, or that the problem lies outside the property boundary entirely — both of which save considerably more than the investigation costs.
For managing agents, facilities teams and landlords, there is a governance benefit too: a documented cause allows a decision to be justified, apportioned between parties where relevant, and closed out properly rather than carried forward year after year.
On-site considerations and disruption
Investigations are largely non-destructive, but they cover more of a site than a single reactive attendance does.
- Access is usually needed to several chambers across the site, sometimes including tenanted or restricted areas, so access is arranged in advance.
- Work can be planned around trading hours, deliveries, shift patterns and occupied periods where areas cannot be released during the day.
- Open chambers in yards, car parks and public areas are guarded and reinstated as the investigation progresses.
- Permits to work, inductions and confined space assessments are dealt with before attendance rather than on arrival.
- Where an investigation cannot reach a conclusion without further work, we say so and set out what that work is instead of guessing.
- Findings are reported clearly enough to be passed to a client, tenant, insurer or contractor without further explanation.
Related services
Services used within an investigation
Drainage problems rarely sit in one category. These are the services most often used alongside this one.
CCTV drain surveys
The primary evidence-gathering tool — pipe condition, defect location and connectivity within the runs.
View serviceDrain tracing & mapping
Establishing where runs, chambers and connections actually go on sites without accurate drainage records.
View serviceHigh pressure water jetting
Cleaning runs so they can be surveyed properly, and testing whether build-up is the cause or a symptom.
View serviceDrain repairs
Acting on the defect once the investigation has confirmed what and where it is.
View serviceCollapsed drains
Where an investigation finds structural failure rather than an obstruction or a build-up problem.
View servicePlanned drain maintenance
Preventing the problem from returning once the underlying cause has been resolved.
View service
Sectors that commission investigations
Typically properties with long histories, multiple occupiers, or drainage that has been altered over time.
FAQs
Questions we are asked about this service
If your question is not covered here, send the site details through and we will answer it directly.
Get an unexplained drainage problem investigated
Describe the property, the symptom and how often it occurs, along with anything already tried. We will set out how we would investigate it and what it would cost.