Stormwater System Maintenance

Surface water, or stormwater, systems are designed to move rainfall away from buildings, car parks, and hardstanding areas. But when maintenance is missed, even a well-designed system can start to fail, leading to standing water, surcharging gullies, blocked catch pits, and localised flooding.

ICE Drainage provides stormwater system maintenance across London and the Home Counties, supporting facilities management teams, property managers, commercial landlords, schools, retail parks, industrial sites, and multi-tenant developments.

What's included in a stormwater system?

Stormwater systems vary by site, but typically include rainwater downpipes and connections, surface water gullies, catch pits and silt traps, inspection chambers and manholes, channel drains, surface water pipework, flow controls such as hydro-brakes, attenuation systems depending on the site, and outfalls to sewers, watercourses, or soakaways.

Because stormwater systems carry debris-heavy runoff, they need regular cleaning to keep performing as designed.

Why stormwater maintenance matters

Poorly maintained surface water drainage can cause localised flooding in car parks and access roads, standing water near entrances and loading bays, slip hazards and site safety issues, water getting into buildings, damage to landscaping and hardstanding, and emergency call-outs during storms.

A planned maintenance approach reduces reactive spend and protects the site during heavy rainfall.

Common causes of stormwater drainage problems

Surface water systems most commonly fail due to silt build-up in catch pits and chambers, leaves and organic debris, especially near trees, litter and debris washed into gullies, blocked channel drains and gratings, restricted flow controls such as hydro-brakes, poor upstream silt control, or damage and defects in the pipework.

Even small restrictions can cause big problems once heavy rain arrives.

Signs your stormwater system needs maintenance

You may need stormwater maintenance if you're noticing gullies overflowing during rainfall, standing water that takes a long time to clear, visible silt and debris in catch pits or manholes, blocked or slow channel drains, flooding that's getting worse over time, or repeated weather-related incidents and call-outs.

For FM teams, these symptoms often show up as recurring winter issues.

Our stormwater system maintenance service

We take a practical, safety-led approach designed for commercial environments.

1) Site review and access planning

We confirm the key drainage assets on site and plan safe access, including any requirements for traffic management or out-of-hours working.

2) Gully, catch pit, and chamber cleaning

We remove silt and debris from surface water gullies, catch pits and silt traps, and inspection chambers and manholes. This restores capacity and stops debris being pushed further into the network.

3) Channel drain cleaning

Where channel drains are present, we clean and clear gratings and channels, outlet connections, and any build-up that's restricting flow.

4) Flow control checks

If the site has a hydro-brake or other flow control device, we can inspect and clean it to reduce the risk of restriction.

5) Condition observations and recommendations

We identify issues that can undermine performance, such as damaged gratings or frames, poor benching or snag points in chambers, areas of repeated silt accumulation, and signs of defects that need further investigation. Where needed, we can recommend a CCTV survey or targeted remedial work.

Planned preventative maintenance for stormwater systems

Stormwater systems are a strong fit for planned maintenance, particularly on sites with large roof areas and hardstanding, high leaf fall, known flood risk areas, regular construction or landscaping activity, or busy car parks and loading bays.

A planned programme helps reduce emergency call-outs, improve site safety, protect assets and surfaces, and demonstrate proactive management to stakeholders.

Stormwater maintenance for facilities management

For FM teams and property managers, stormwater maintenance supports better winter readiness and risk control, reduced reactive spend and fewer incidents, clear reporting for budgeting and approvals, and consistent standards across multi-site portfolios. We can support both reactive call-outs and planned programmes.