Silt Traps & Catch Pits

If your gullies, channel drains, or surface water lines keep silting up, the problem often isn't the pipework, it's the lack of anywhere for silt and debris to settle first. Without that, everything gets carried straight into your drainage system, leading to blockages, flooding, and repeated maintenance call-outs.

ICE Drainage installs and maintains silt traps and catch pits across London and the Home Counties, supporting commercial property teams, hospitality sites, and facilities management with practical solutions that protect drainage assets and reduce repeat issues.

What is a silt trap?

A silt trap is a chamber or feature designed to slow down water flow so heavier material, such as silt, grit, sand, and debris, can settle out before the water continues into the drainage system. Silt traps are commonly used in surface water drainage systems, car parks and service yards, loading bays and external hardstanding, sites with landscaping runoff, and areas prone to leaf litter and debris.

By capturing solids early, silt traps help prevent blockages further down the line and reduce how often you need disruptive jetting.

What is a catch pit?

A catch pit is a chamber installed in a drainage run that gives debris and silt somewhere to collect, provides an access point for inspection and maintenance, and protects downstream pipework, soakaways, and attenuation systems.

Catch pits are especially useful upstream of soakaways, attenuation tanks, flow controls, and long surface water runs. They're a simple addition that can drastically improve how reliable and maintainable a system is.

When you need silt traps or catch pits

You may benefit from installing or upgrading silt traps and catch pits if you're seeing repeated silt build-up in gullies and surface water lines, channel drains that overflow during rainfall, blocked surface water drains in car parks or yards, soakaways that have failed due to silt, attenuation systems needing frequent cleaning, or flooding caused by debris being washed into the system.

If you're constantly paying for reactive clearance, adding the right interception points is often the most cost-effective long-term fix.

Commercial applications

We commonly install and maintain silt traps and catch pits for hotels and leisure sites with large external areas, restaurants and pubs with service yards and bin areas, facilities management teams managing multiple sites, commercial buildings with car parks and loading bays, and schools and public buildings where leaf litter and runoff are common.

The goal is to keep surface water systems flowing and reduce disruption.

Our approach: assess, install, and make it maintainable

1) Site assessment

We look at where silt and debris is entering the system, the existing gully and channel drain layout, the falls and flow routes, where interception would work best, and any access or maintenance constraints.

2) Recommendation and design

We recommend the right type and location for a silt trap or catch pit, suitable chamber sizing for the catchment area, how it connects into existing pipework, and any additional improvements, such as channel drain upgrades or repositioning a gully.

3) Installation and reinstatement

We install with long-term performance in mind, using correct excavation and base preparation, proper connections and flow direction, accessible covers and safe access points, and sensible reinstatement of the surrounding area where agreed.

Keeping silt traps working

Silt traps and catch pits only protect your system if they're maintained. We can support planned maintenance that includes routine emptying and cleaning of chambers, inspecting inlet and outlet condition, checking for structural damage or collapse, and clearing upstream channel drains and gullies. For FM teams and hospitality groups, this can be built into a wider planned maintenance programme.

Protecting soakaways and attenuation systems

If you've invested in a soakaway or attenuation tank, protecting it from silt is essential. A failed soakaway can be expensive to put right. Installing upstream interception, such as catch pits or silt traps, is one of the best ways to extend the asset's life, reduce blockages, improve performance during heavy rainfall, and lower your long-term maintenance costs.