Percolation Tests carries out BRE365 soakaway percolation testing and foul infiltration testing across Nottingham, supporting planning applications and drainage design throughout the city and surrounding county.
We are based in Wolverhampton, about 48 miles away, and Nottingham is well inside the area we cover as standard. We have carried out 16 tests within twenty-five miles of Nottingham.
Ground conditions in Nottingham
Nottingham is well known for its Sherwood Sandstone bedrock, which generally percolates well and has historically made the area suitable for soakaway drainage — the sandstone is even riddled with man-made caves cut into it for this reason. However, overlying clay deposits and made ground in parts of the city can still produce slower percolation results, so a site-specific test remains essential rather than relying on the area’s sandstone reputation alone.
In practice that means results around Nottingham are rarely uniform. Sandstone can take water well, but where glacial till, boulder clay or made ground sits over it the picture changes within a very short distance — one corner of a plot can drain freely while another barely moves. Ground water matters here too: BRE365 requires the base of a soakaway to stay clear of the water table, and a site can fail on that alone however well the soil itself drains. None of it can be read off a map, which is why the test is asked for.
What we test for
- BRE365 percolation testing for surface water soakaway design
- Foul effluent infiltration testing (Part H) for septic tanks and treatment plants
- Drainage strategy support for planning submissions
What a BRE365 test involves
The method comes from BRE Digest 365, and it takes longer than most people expect. It is not one hole and a stopwatch.
- Trial pits are dug where the soakaway is proposed and taken below its intended base. How many depends on the size of the site and what the drainage design needs.
- Each pit is filled to at least 75% of its effective storage depth before timing begins.
- Each pit is then filled and timed three separate times, recording how long the water takes to fall from 75% to 25% of the effective storage depth.
- The slowest result is the one used, so the design is based on the worst case rather than a flattering one.
Because every pit is tested three times and has to drain fully in between, a proper test is not an hour’s work. We would rather tell you a site is unsuitable than hand over a figure that will not stand up at planning.
Planning conditions in Nottingham
Applications in the Nottingham area are dealt with by Nottingham City Council, and drainage conditions are attached routinely — particularly on rural plots, barn conversions and self-builds with no mains surface water connection. The condition normally asks for infiltration testing to BRE365 and a soakaway design based on the result, approved before work starts.
Testing early is worth the trouble. If infiltration turns out not to be viable the drainage strategy has to change, and discovering that after the groundworks are priced is an expensive surprise.
Septic tanks and foul drainage
Surface water and foul drainage are tested differently, and the results are not interchangeable. A drainage field for a septic tank or treatment plant is sized using BS 6297, which Part H of the Building Regulations refers to. If your site near Nottingham needs both a soakaway and a drainage field, we can carry out both tests in one visit rather than two.
What you receive
- A full report with the recorded times for every pit and every fill
- The calculated infiltration rate, ready to hand to your engineer or planner
- Trial pit locations and depths
- Photographs of the testing on site
- A clear statement of whether a soakaway is viable, and if not, why not
Coverage
We test across Nottingham city centre, West Bridgford, Beeston, Arnold, Carlton, and the surrounding suburbs. Available Monday to Friday.
Get a quote
Contact us for a free, no-obligation quote for percolation or infiltration testing anywhere in Nottingham. Call 01902 475653 or request a quote online.
Nearby areas we cover
Recent work near Nottingham
Percolation testing around Nottingham
Each dot is a site we have tested. 13 within twenty-five miles of Nottingham.