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Pit dimensions and the three test timings in; the soil infiltration rate and the storage volume the BRE Digest 365 method requires out, with the storm-duration table behind it.
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Quick answer: The Environment Agency’s report for 2 to 8 October 2026, published on 9 October, shows England has received just 10% of its long-term average October rainfall so far (6% in the east and south-east). Yorkshire moved into drought on 9 October, taking the total to 11 areas. Reservoirs are 54% full, 21% below average. Groundwater is still in its seasonal decline, with Tilshead and Chipstead classed exceptionally low. Infiltration tests taken now are a best case, not a design case.
What the report says
Rainfall this month has been well short of what the aquifers need. Weekly totals ranged from 5mm in east England to 24mm in the north-west, leaving October to date at 6% of the long-term average in the east and south-east, 16% in the north-west and north-east, and 10% for England overall. September as a whole was already dry, at 65% of average, according to the previous weekly report.
- Reservoirs: England is 54% full, down 1.3 points on the week and 21% below average for the time of year. 19 reservoirs or groups are under half full and eight are classed exceptionally low (Abberton, Ardingly, Clatworthy, Colliford, the Dove Group, Hanningfield, the Pennines Group and Wimbleball).
- Groundwater: levels are following their expected seasonal decline. All chalk sites are normal or lower, several notably or exceptionally low. Tilshead (Upper Hampshire Avon Chalk) and Chipstead (Epsom, North Downs Chalk) are exceptionally low; Jackaments Bottom (Cotswolds limestone) is notably low.
- Rivers: flows rose at just over half of the roughly 55 sites reported, but 26 sites (48%) are still notably or exceptionally low.
- Drought status: 11 areas are in drought, including Yorkshire from 9 October. The North East, Cumbria and Lancashire, and Greater Manchester, Merseyside and Cheshire remain in prolonged dry weather.
- Hosepipe bans: temporary use bans apply in all or part of the areas of 10 water companies.
The next dates to watch are the National Drought Group meetings on 12 and 19 October, and 31 October, when formal section 57 abstraction restrictions in parts of East Anglia end. We have not seen the outcome of the 12 October meeting from a primary source.
Why it matters for drainage evidence
Our earlier coverage explained why September tests flatter a soakaway: dry ground takes water quickly, and the water table sits at its annual minimum. The new figures extend that window. With October rainfall at a tenth of normal, recharge has not begun, so the same caution now applies through the whole of this month and probably into November.
In practice:
- Date-stamp every test and record antecedent rainfall and the groundwater level you actually measured.
- Do not use today’s water table as the design water table. Take the highest expected groundwater level from long-term monitoring, borehole logs or winter observation, then apply your separation distance to that.
- Stress the slowest fill. BRE Digest 365’s three-fill approach controls short-term wetting, not a multi-year deficit.
- Expect questions from the LLFA. With SuDS now tied to national standards in the NPPF, a test report that ignores the season is easy to challenge.
The wider policy picture
Separately, trade press reported on 12 October that Government has launched a Flood and Drought Resilience Taskforce, led by Floods and Drought Minister Emma Hardy, with a first meeting on 14 October. Water Magazine’s report says it will feed a longer-term resilience strategy and mentions easier on-site reservoirs. It does not describe changes to Building Regulations, planning or Part G, and we have not seen the Defra announcement itself, so treat this as context rather than a rule change. The Part G water efficiency position is unchanged.
What to do now
If you have a drainage strategy relying on a soakaway designed from an autumn test, flag the test date in your report and record the seasonal assumptions you made. Where the design only works at the measured rate, consider winter monitoring before the condition is discharged.
SoakMonkey will run the BRE Digest 365 calculation from your trial pit results; the judgement about whether the test conditions represent a wet winter still needs to be recorded in your report.
Sources: Dry weather and drought in England: 2 to 8 October 2026 (Environment Agency, 9 October 2026) · Dry weather and drought in England: 25 September to 1 October 2026 · Water Magazine, 12 October 2026