Drain Alterations & Diversions

If a drain is in the way of an extension, a new structure, or a change to your building's layout, it needs to be properly moved or diverted, not just worked around. Get it wrong and you risk a drain that no longer falls correctly, can't be accessed for maintenance, or conflicts with foundations and services.

ICE Drainage carries out drain alterations and diversions for homeowners, developers, and commercial clients across the UK. We plan the new route, carry out the work safely, and make sure the finished system performs as well as, or better than, what was there before.

What are drain alterations and diversions?

A drain alteration changes part of an existing drainage run, for example adjusting its route, level, or connection point. A diversion moves a section of drain around an obstruction entirely, such as new foundations, a basement, or a structure being built over the original line.

Common reasons for alterations and diversions include:

• Extensions or new structures built over or near an existing drain
• Foundations or piling that would otherwise clash with the drain's route
• Basement or lower-ground developments requiring a new fall or connection
• Changing a building's layout, including new kitchens, washrooms, or drainage demand
• A drain that's in poor condition and easier to reroute than repair in place
• Coordinating drainage with wider groundworks or landscaping

What we consider before altering or diverting a drain

Getting this right depends on more than just moving the pipe. We look at:

• The drain's current route, depth, and condition, usually confirmed with a CCTV survey first
• Whether the line is public or private, and if the water company needs to be involved
• The correct fall and gradient for the new route, so the drain still flows properly
• How the diversion will connect back into the existing system or a new discharge point
• Access for future maintenance, including manholes and inspection chambers
• Any building regulations or planning requirements tied to the wider project

Our process

1) Survey and planning

We confirm the existing drain's route and condition, and work out the best new path based on your building plans, ground conditions, and any constraints on site.

2) Design and agreement

We propose the alteration or diversion route, including new falls, connections, and access points, and agree this with you and your architect or contractor before work starts.

3) Excavation and pipework

We excavate along the new route, install the new pipework to the correct line and level, and connect it in cleanly at both ends.

4) Testing and reinstatement

We test the new section to confirm it's flowing correctly and watertight, then reinstate the surface, whether that's ground, paving, or flooring, as agreed.

5) Handover

We provide details of the new drain route and any new access points, which is particularly useful for future maintenance or if drainage plans need updating.

Coordinating with your wider project

Drain alterations rarely happen in isolation. We're used to working alongside architects, structural engineers, and main contractors on extensions, refurbishments, and new builds, and we can time the work to fit around the rest of the project rather than holding it up.

Book a drain alteration or diversion

If you need a drain moved, altered, or diverted as part of building work, ICE Drainage can help.

Contact ICE Drainage to discuss your project. We'll survey the existing drain, plan the new route, and carry out the work properly from start to finish.