Morpeth Sewage Works £27m Upgrade Begins Late October

Work on a £27 million upgrade of Morpeth Sewage Treatment Works is due to start in late October. Northumbrian Water says the scheme will cut the phosphorus in the treated water it returns to the River Wansbeck. It will also give the works more capacity for a growing town.

The company announced the project on 13 October (Northumbrian Water). Its partner Mott MacDonald Bentley will build it.

What the work includes

According to Northumbrian Water, the programme covers:

• new treatment equipment, built inside the existing works
• upgrades to the final stage of treatment, so the water leaving the site is cleaner
• more treatment capacity, to cope with population growth across the catchment
• a temporary site compound next to the works while building goes on

The money comes through the Water Industry National Environment Programme (WINEP). That is the list of environmental improvements regulators require water companies to carry out.

How long it will take

The press release says construction will last “around two years”. The company’s own project page gives a longer timetable. It lists a start in October 2026 and an estimated end date of March 2029, and describes the investment as “up to £27 million” (Northumbrian Water Community Hub).

Why phosphorus matters

Phosphorus is a nutrient. Too much of it in a river feeds algae, which can choke plant life and the wildlife that depends on it. Northumbrian Water’s project page makes the same point.

The Environment Agency’s latest assessment of this stretch of river, the Wansbeck from the Font to the Bothal Burn, is mixed (Environment Agency Catchment Data Explorer):

• overall ecological status: Moderate, in both 2019 and 2022, below the Good that rivers are meant to reach
• phosphate: High, the best grade, in both years
• water plants (macrophytes): Poor

So on the agency’s last published figures, phosphate in this stretch was already rated well. The weak points were elsewhere. Northumbrian Water has not said which reading or which length of river the new limits are aimed at.

The storm tank spills

The upgrade is about everyday treatment, not storm overflows. But residents asking about the river will want the overflow record too, and it is public.

The works has a storm tank that overflows into the Wansbeck when heavy rain overwhelms it. The Environment Agency’s annual returns show how often that happened (EA storm overflow annual returns):

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The return gives a long-term average of 25.33 spills a year for the tank, so 2025 was below it and 2024 well above. The hours are the raw monitored time, before the counting rule that groups spills into 12 and 24-hour blocks.

A second overflow at the inlet to the works recorded 15 spills, about 28 hours, in 2025. That figure is incomplete. Its monitor worked for only 38% of the year because of a set-up problem, which the return says was resolved in August. The same overflow recorded no spills in 2023 or 2024. A sewer overflow in the town, Morpeth CSO D, recorded none in any of the three years.

Northumbrian Water has not said whether the new work will change how often the storm tank overflows.

What it means for you

• Expect construction traffic near the works from late October, with a compound set up alongside. Northumbrian Water has not yet published delivery routes or working hours.
• Follow the project page for updates. The company says it will post progress there and answer questions left in the comments.
• See the other overflows near you. The figures above are whole-year totals. The Environment Agency’s spill frequency map shows every monitored overflow in the county.

Northumbrian Water’s project manager, Paul Davison, said the company would “work closely with our delivery partners to minimise disruption wherever possible”.

For other work on Morpeth’s roads, see our Northumberland roadworks page.