East Riding of Yorkshire councillors have told Yorkshire Water that its progress in cutting sewage and wastewater discharges across the region is not keeping pace with the rest of England, at a meeting of the council's Environment & Regeneration Committee held earlier this month at County Hall in Beverley and reported on 14 September 2026 (Hull Live).
The committee heard that while discharge hours across England have fallen by more than 30%, the reduction recorded in East Yorkshire is only 6.4%, despite rainfall running about 8% lower than the 2021 baseline year used for the comparison (Hull Live).
Key takeaways
- Yorkshire Water's East Riding discharge hours have fallen only 6.4% against a national fall of more than 30%, against a baseline of 8% lower rainfall than 2021 (Hull Live).
- The company does not currently convert discharge data into volume statistics, so it cannot quantify how much wastewater is spilling across the East Riding (Hull Live).
- Just 16 sites in East Yorkshire account for half of all recorded discharge hours, according to research by Cllr Phil Redshaw (Hull Live).
- Yorkshire Water has agreed to review those 16 sites and to meet the councillor again on storm overflow reduction activity (Hull Live).
- A wider company investment of £1.5bn over five years is under way to cut sewage discharges into rivers and coastal waters, with a separate £250m-plus programme on Yorkshire's coast (BBC).
What happened at the East Riding committee
At the Environment & Regeneration Committee meeting at County Hall in Beverley, the company was praised for some improvement in reducing the number of discharges, but councillors argued the improvement is not keeping pace with other water companies around England (Hull Live).
Yorkshire Water was criticised for basing its targets on the number of discharges and their total time, rather than on the volume of waste discharged, and the meeting heard the company does not currently convert discharge data into volume statistics, meaning it cannot quantify the amount of wastewater discharged across the East Riding (Hull Live).
Cllr Phil Redshaw, Liberal Democrat member for Cottingham North and the group's spokesperson on environment and transport, told the meeting: "I am also pressing them to establish what options are open to them to calculate or measure the volumetric flow rates across all or even part of the system, since any other measures remain extremely subjective. The key issue is not simply the number of incidents, but the duration of the discharges" (Hull Live).
He added: "I want to know what Yorkshire Water is doing at these worst-performing sites and what reduction in discharge hours we can expect to be delivered in the next four years" (Hull Live).
His research has found that just 16 sites across East Yorkshire account for half of all discharge hours, and the company has now agreed to a follow-up meeting with Cllr Redshaw on storm overflow reduction activity and to review the sites identified, with further research shaping investment plans into water quality (Hull Live).
Adam Ashman, from Yorkshire Water, told the meeting that more needed to be done but explained a volumetric data-gathering system was a clear ambition, and that a major challenge in the region is groundwater-induced storm overflows: "We're looking at a number of ways to address those. A huge amount of work is going on at individual sites to look at how we deal with this operationally or whichever means we've got to improve that" (Hull Live).
Cllr Redshaw also raised the issue of longer-term security of water supplies, welcoming the fact that Yorkshire Water has so far avoided widespread hosepipe restrictions but warning that several new service reservoirs are under construction and that there is currently no new large traditional reservoir under construction in Yorkshire (Hull Live).
Separately, Yorkshire Water has told campaigners that it is investing £1.5bn over five years to reduce sewage discharges into rivers and coastal waters, with projects under way across West and North Yorkshire, and that the programme followed a previous £180m investment and helped cut discharges by 24.5% in 2025, after a 12% reduction in 2024 (BBC).
Specification read
The reported performance gap in East Riding is measured in discharge hours, not flow: only 16 sites carry half the hours, rainfall is 8% below baseline, and the company does not currently publish volumetric spill data (Hull Live). Without a published m³/day spill figure, the engineering scale has to be inferred: a 6.4% reduction in hours against a national 30%+ reduction implies those 16 sites are still spilling for tens of thousands of hours a year, and a typical combined-sewer overflow at this class of catchment will pass on the order of tens of thousands of cubic metres per storm event, i.e. flows in the tens of MLD range per site during peak wet weather (general industry range, not from the sources).
This is fundamentally a hydraulic and primary-stage problem, not a biological-treatment problem. The treatment train that addresses it runs screening → grit removal → primary settlement → biological stage (A2O, MBBR, SBR or MBR depending on footprint and consent) → tertiary filtration and disinfection (UV or chlorination), with storm storage and flow attenuation sitting ahead of the works. The 16 hot-spot sites in East Riding are about attenuation, infiltration reduction, and primary-stage capacity, because the spills are triggered by groundwater ingress and storm loading rather than by failure of the secondary biological stage (Hull Live).
Yorkshire Water has also pointed to a £1.5bn five-year programme and a £250m-plus coastal investment, including a wastewater and surface-water scheme at Scarborough still in community consultation (BBC). If your catchment looks like this one — combined sewer with high groundwater ingress, peak wet-weather flows that exceed the biological-stage hydraulic capacity, consent pressure around discharge duration and receiving-water quality, and a regulator asking for volume rather than event-count data — then the procurement focus for the next four years is on attenuation tanks, primary settlement upgrade, MBBR or MBR capacity, and flow-monitoring on every overflow, not on a new tertiary polish. Operators comparing options in this class of works can shortlist through our Municipal hub and review packaged primary-plus-biological skid configurations on our Integrated Sewage Treatment page; for a comparable buyer's-engineering view of a UK catchment under similar pressure, see our Effluent Treatment Plant in London: 2026 Buyer's Engineering Guide, and for the upstream physical-primary decision that typically precedes this kind of biological upgrade, our DAF or Clarifier for Fabricated Metals Wastewater in Whitewhite: 2026 Buyer's Guide walks through the trade-offs.
FAQ
What exactly did the East Riding council committee criticise Yorkshire Water for?
It criticised the company for measuring progress in number and duration of spills rather than volume, and for a 6.4% reduction in East Riding discharge hours against a national fall of more than 30% on 8% lower rainfall than 2021 (Hull Live).
How much is Yorkshire Water committing to spend on sewage discharges?
Yorkshire Water has said it is investing £1.5bn over five years to cut sewage discharges into rivers and coastal waters, building on a previous £180m programme, and has earmarked more than £250m for work on Yorkshire's coast, including a Scarborough scheme still in community consultation (BBC).
What is the lead time on a storm-storage or attenuation tank at a UK wastewater site?
Attenuation tanks typically run 9–18 months from order to commissioning on a UK municipal site, with site civils and consents on the critical path (general industry range, not from the sources). The East Riding committee has asked Yorkshire Water to set out the next four years of discharge-hour reductions at its 16 worst-performing sites, which is the window in which such assets would be designed and built (Hull Live).
How should a buyer shortlist suppliers for a groundwater-driven overflow fix?
Shortlist on hydraulic first-stage performance and on verified flow-monitoring rather than on tertiary polish: ask bidders for m³/day attenuation at peak wet weather, infiltration-reduction evidence, and continuous overflow flow data, and weigh those against biological-stage upgrade cost (general industry range, not from the sources). The East Riding debate is exactly that shift, from event counts to volumetric evidence, that the company has said it will adopt (Hull Live).
