Storm overflow register · Yorkshire Water

Permit Applied For sewage works: storm overflow spills 2025

Permit Applied For sewage treatment works, run by Yorkshire Water, has 14 monitored storm overflows discharging to Permit applied for. In 2025 they recorded 568 spills totalling 3,810 hours, against 829 spills and 7,225 hours in 2024. By hours spilling, it ranks 1 of 283 Yorkshire Water works, where 1 spilled longest.

Every spill in 2025

Each blue mark is one spill, placed by when it started and sized by how long it lasted. Hover over a mark for the date and duration.

Hours spilling by month, 2025

Hours, measured by the event duration monitor.

Longest single spills

Started (GMT)	Overflow	Duration
5 Jan 2025, 13:00	Permit applied for	5.1 days
13 Nov 2025, 11:15	Permit applied for	3.7 days
20 Feb 2025, 15:45	Permit applied for	2.9 days
20 Nov 2025, 12:30	Permit applied for	2.8 days
29 Nov 2025, 16:45	Permit applied for	2.7 days

Estimated 2025 spill volume and pollution

Estimate, not a measurement. Monitors record how long an overflow spills, not how much. This calculator back-calculates a spill rate from the size of the works, using the Environment Agency's permit formulae, and multiplies it by published storm-sewage concentrations. How it works.

This works serves fewer than 2,000 people, or was not matched to a UWWTD report, so its size is not published. The population equivalent above is a placeholder of 1,000. Enter the population served if you know it.

Volume, central estimate65,282 m³range 26,003 – 163,894 m³

In litres65.3 millionrange 26.0 million – 163.9 million L

Olympic swimming pools26at 2,500 m³ each

Organic load, as people's raw sewage97,923person-days of untreated BOD

Assumed spill rate while spilling: 1.9 – 11.9 L/s (central 4.8 L/s), from a dry-weather flow of 1.9 L/s.

Pollutant released	Low	Central	High	Concentration used (low / typical / high)
BOD₅ (organic load)	1,040 kg	5,875 kg	32,779 kg	40 / 90 / 200 mg/L Low/high: Europe range, Ellis & Jenkins 2005; typical: UK, Ellis & Jenkins 2005 (both via botturi)
Suspended solids	2,730 kg	27,745 kg	118,167 kg	105 / 425 / 721 mg/L Low/high: Europe range; typical: UK, Ellis & Jenkins 2005 (via botturi)
Ammonium-N	49 kg	411 kg	1,524 kg	1.9 / 6.3 / 9.3 mg/L Low: Germany, Brombach 2005; typical/high: Paris range 3.3–9.3 midpoint and top, Gasperi 2012 (via botturi); no UK value found
Total phosphorus	31 kg	170 kg	885 kg	1.2 / 2.6 / 5.4 mg/L Low/high: Paris, Gasperi 2012; typical: Slovakia (via botturi). UK figure of 10 mg/L treated as an outlier
E. coli	2.6 trillion organisms	65.3 trillion organisms	1.6 × 10¹⁵ organisms	10,000 / 100,000 / 1.0 million per 100 mL Median range at CSO and retention-tank outlets, Stott et al. 2018 (via botturi); typical = log midpoint

Low combines the low spill rate with low concentrations, and high combines high with high, so the true figure is very likely inside the range. Long spills become more diluted as they go on, so the central figure tends to overstate the load of long events. The calculator does not estimate the effect on the receiving water, which depends on river flow or tide at the time of the spill.