Drainage RAMS: a complete guide for UK drainage and groundworks contractors (2026)

Why drainage contractors need a RAMS

A RAMS is a Risk Assessment and Method Statement combined into one document. For drainage work it is the document that proves you have thought through the confined spaces, the excavation and the buried services before anyone climbs into a chamber or breaks ground.

Drainage is one of the genuinely dangerous trades. The two things most likely to kill on a drainage job - a confined space full of toxic gas, and an excavation that collapses and buries someone - are exactly the hazards a thin RAMS glosses over. Add raw sewage carrying disease, buried gas and electric services, and work in live highways, and it is clear why a main contractor will scrutinise your RAMS hard before letting you on site.

On any commercial site, new build, civils project, or work running under a principal contractor and CDM 2015, a written RAMS is expected and almost always mandatory before you can start. Given the risks involved, even smaller drainage jobs should have a proper documented assessment.

Who asks for a drainage RAMS?

The people who will want to see it include main contractors and principal contractors letting you onto their site, water companies and utilities, councils and highways authorities, housebuilders and civils contractors, and facilities managers. A clear, trade-specific RAMS keeps your team safe and gets you through the approval gate without delay.

The hazards a drainage RAMS must cover

A generic RAMS will not pass a competent contractor's check, because it will not properly address the hazards that make drainage dangerous. These are the ones that matter.

Confined spaces and toxic gas: the biggest killer

Drains, sewers, chambers, manholes and tanks are confined spaces under the Confined Spaces Regulations 1997. People die in them every year. The danger is not just being trapped - it is hydrogen sulphide, methane and carbon monoxide building up, and oxygen being displaced, sometimes with no warning smell. Hydrogen sulphide in particular deadens the sense of smell and then kills.

This is the most important section of a drainage RAMS, and the one an assessor reads first. Your document must set out a safe system of work for confined-space entry: atmosphere testing with a calibrated gas monitor before and during entry, forced ventilation, a permit-to-work system, trained and competent operatives, and - crucially - an emergency rescue plan that does not rely on someone else climbing in after a casualty. A drainage RAMS that treats confined spaces vaguely will and should be rejected.

Excavation collapse

The second great killer in drainage is the trench that caves in. A cubic metre of soil weighs over a tonne, and a collapse buries and suffocates before anyone can react. Excavation safety follows the HSE's guidance, including HSG185, and the HSE's guidance on excavations.

Your RAMS should set out how excavations will be made safe: trench support such as trench boxes and shoring, or battering and stepping the sides to a safe angle, keeping spoil and plant back from the edge, safe access and egress, and daily inspection by a competent person. Vague references to "the excavation will be made safe" do not cut it - the method must say how.

Sewage, leptospirosis and biohazard

Contact with raw sewage and contaminated water exposes drainage workers to infection, including leptospirosis (Weil's disease) from rat urine, hepatitis and gastrointestinal illness. Leptospirosis can be fatal and starts with flu-like symptoms that are easy to dismiss.

Your RAMS should cover the controls: gloves and protective clothing, covering cuts and grazes, not eating or smoking without washing, proper welfare and washing facilities on site, and making operatives aware of the symptoms of Weil's disease so they can tell a doctor about sewage exposure. This is a hazard unique enough to drainage that covering it well marks out a credible document.

Buried services

Digging strikes underground gas, electricity and water can cause explosion, electrocution and flooding. Safe digging follows the HSE's guidance HSG47 on avoiding danger from underground services. Your RAMS should set out obtaining service plans, using a cable avoidance tool (CAT and genny) to locate services, hand-digging trial holes near known services, and safe-digging practice rather than going straight in with a machine bucket over unknown ground.

Traffic management

Drainage work is often in or beside live roads. Working in the highway brings traffic management duties under the New Roads and Street Works Act and the Chapter 8 signing requirements. Your RAMS should cover the traffic management plan, signing, lighting and guarding, exclusion of the work area from traffic, and high-visibility clothing. Being struck by a vehicle is a real and frequent cause of death in roadside work.

Plant, manual handling and slips

Excavators and other plant working alongside people on foot create a struck-by and crush risk - your RAMS should set out exclusion zones, banksman arrangements and segregation of plant and people. Manhole covers, pipes and chamber rings are heavy and awkward, bringing manual handling duties under the Manual Handling Operations Regulations 1992, so cover lifting aids and team lifts. Open excavations and chambers are also a fall risk for the team and the public, so cover edge protection, covers and barriers.

A worked example: RAMS for a new foul connection to an existing sewer

It helps to see how the hazards turn into an actual method statement. Take a common job: excavating to lay a new foul drain and connecting it into an existing sewer via a manhole, on a site beside a live road. Here is how a sound RAMS would walk through it.

Before work starts

The RAMS records that service plans have been obtained and a cable avoidance tool will be used to locate buried services before digging, that the manhole connection is identified as confined-space work requiring atmosphere testing and a permit, and that a traffic management plan is in place for the roadside element. It confirms trained and competent operatives, a gas monitor and rescue equipment on site, and welfare and washing facilities for sewage exposure.

Sequence of work and controls

Set up: install traffic management and signing, establish the exclusion zone, and brief the team. Locate services: scan with the cable avoidance tool and hand-dig trial holes near any known services before machine digging. Excavate: dig the trench, supporting it with a trench box or battering the sides to a safe angle, keeping spoil and the excavator back from the edge, with safe access and egress and daily inspection by a competent person. Lay the drain: install pipework in the supported trench, with plant and people segregated and a banksman for the machine. Connect at the manhole: treat the chamber as a confined space - test the atmosphere with the gas monitor, ventilate, enter only under the permit with the rescue plan ready, and never rely on someone climbing in after a casualty. Sewage hygiene throughout: gloves, covered cuts, no eating or smoking without washing. Backfill and reinstate: backfill the trench, reinstate the surface, remove traffic management, and clear the site.

Why this reads as competent

The assessor sees the two killers - confined space and excavation collapse - controlled with real measures, buried services located before digging, traffic managed and sewage hygiene covered. That is the difference between a RAMS for this job and a template with the name changed.

A pre-work checklist for drainage RAMS

Before you submit a drainage RAMS, or before the team starts on site, run through a short check. A RAMS that can answer yes to these is one that will pass and, more importantly, keep people safe.

• Confined space planned - if any chamber, sewer or tank entry is involved, is there atmosphere testing, ventilation, a permit and a rescue plan that does not rely on someone following the casualty in?
• Excavation made safe - does the method say how - trench support or battering, spoil and plant kept back, safe access and egress, daily inspection by a competent person?
• Services located - are service plans obtained, a cable avoidance tool used and trial holes hand-dug before machine digging?
• Traffic managed - for roadside work, is there a traffic management plan with signing, lighting and an exclusion zone?
• Plant and people segregated - are exclusion zones and a banksman set out where excavators work near operatives on foot?
• Sewage hygiene - are gloves, covered cuts, washing facilities and awareness of Weil's disease covered?
• Manual handling - are lifting aids and team lifts specified for manhole covers, pipes and chamber rings?
• Fall protection - are open excavations and chambers protected with edge protection, covers and barriers for the team and the public?

Common reasons a drainage RAMS gets rejected

Knowing why documents get sent back is the fastest way to write one that does not. These are the failings an assessor sees most often on drainage RAMS, and given the lethal hazards, an assessor scrutinises these documents hard.

Confined-space entry has no rescue plan. The most serious failing - identifying a chamber or sewer entry but not setting out atmosphere testing, a permit and how someone would actually be rescued. This is an immediate rejection because it is exactly where people die.

Excavation is vague. "The excavation will be made safe" without saying how - support, battering, inspection - does not satisfy an assessor who knows trenches collapse and kill.

Buried services are not located. A method that goes straight in with a machine over unknown ground, with no service plans or cable avoidance tool, is a frequent and dangerous gap.

Traffic management is missing. Roadside drainage work with no traffic management plan ignores a common cause of death in this trade.

Sewage hygiene is ignored. Saying nothing about leptospirosis, washing facilities and hygiene for work in contact with sewage overlooks a hazard unique to the trade.

How to write a drainage RAMS that passes

A RAMS that gets approved first time shares a few features whatever the trade.

Make it specific to the job

The fastest way to get a RAMS rejected is to submit something obviously generic. Name the site, the actual work - whether it is new drainage installation, repair, CCTV survey, jetting, or connection to a sewer - the depth and ground conditions, whether confined-space entry is required, and the real traffic arrangements. An assessor can tell within seconds whether the document describes this job or is a template with the name changed.

Follow the sequence of work

The method statement should walk through the job in order: setting up and traffic management, locating services, excavation and support, the drainage work itself including any confined-space entry, backfill and reinstatement, and clearing the site. Each stage links to the hazards it creates and the controls that manage them.

Rate the risks honestly

The risk assessment side rates each hazard by likelihood and severity, then again after your controls are in place. This residual-risk approach follows HSE's risk assessment guidance and is what a competent assessor expects, with confined spaces and excavation rated as the life-threatening hazards they are.

Keep it readable

The people who need to follow a RAMS are the operatives on site, not just the assessor. Plain language, a clear sequence and a short list of real controls beat pages of boilerplate nobody reads - and in a trade where the hazards are lethal, a RAMS that is actually read and understood matters more than most.

Doing it the fast way

Writing a full drainage RAMS by hand for every job is exactly the paperwork that eats evenings. That is the problem Complys was built to solve: answer a few questions about the job and the trade, and it generates a complete, drainage-specific risk assessment and method statement you can edit, download and share. The hazards above - confined spaces, excavation, sewage, buried services, traffic - come built into the templates, so you start from a document that already knows the trade rather than a blank page.

If you want the wider picture first, our guide to what a RAMS is and how to write one covers the fundamentals, and the difference between a RAMS and a risk assessment clears up the most common confusion. You can also see every trade we cover on the RAMS builder hub.

However you produce it, the goal is the same: a RAMS that keeps your team safe, gets you onto site without delay, and stands up when a contractor checks it.