East Tanfield STW

Storm overflow run by Northumbrian Water, discharging into Causey Burn.

Inlet storm overflow at sewage treatment works North Durham constituency
Right now
No live feed
Northumbrian Water does not publish a live status for this overflow; only the annual figures below are available.

"Not discharging" means the company's monitor reports no discharge right now — not that the water is clean. The feed publishes status only; no discharge volume is measured.

2026 so far
26spills
at least 23 h discharging on 26 days · live feed, before 28 Feb via Top of the Poops, not yet official · 21 discharges whose end the feed did not report (counted, no hours)
2025 official
78spills
321 h · −11% on 2024
Rank in Northumbrian Water
#29
of 1,547 overflows by 2025 spills (1 = most)
Monitor in 2025
100% working
Long-term average 93.6 spills a year

Year by year

The Environment Agency's official annual returns, counted the EA's way (12/24-hour spills). 2026 is our own running count, the same way, from the live feed: our own log of it begins on 28 February, and the discharges before that are Top of the Poops' record of the same feed. The feed reports only each overflow's latest discharge, so a discharge it moved past before we saw it end is counted as one spill with no hours: the hours are a floor. The official figure is published next spring.

2024
88 spills · 583 hmonitor 100%
2025
78 spills · 321 hmonitor 100%
2026so far
26 spills · at least 23 h

A spill is the EA's 12/24-hour count: the first 12 hours of a discharge count as one, each further 24 hours with discharge as one more. "Monitor" is the share of that year the monitor was working, so a 0 beside a working monitor is a real zero; "no data" means the monitor produced no usable data that year — not zero. Years before 2024 are matched to this site by name and location, because the EA's site IDs changed that year; a monitor figure beside one of them means the outlet's permit confirms the match.

Downstream of this overflow

The next gauge downstream that the river map places is Team Valley (River Team), 15.1 km along the river.

Water-sampling points downstream

The nearest Environment Agency sampling points the river map places below Team Valley. Points between this overflow and that gauge cannot be put in order with it on the map, so they are not listed.

A sample is dated: it is not the river now, and its results are on its own page. A sample taken after a discharge does not show that the discharge caused what was measured. Samples: Environment Agency Water Quality Archive, © Environment Agency and/or database right 2026, Open Government Licence v3.0.

A river gauge measures the level of the river; it does not measure this overflow's discharge, and a spill does not by itself explain a change there. Traced on OS Open Rivers (edition 2026-04), which leaves out many small channels.

Contains OS data © Crown copyright and database rights 2026.

What the 2025 return says

From Northumbrian Water's annual return to the Environment Agency for this overflow.

High-spill review
Performance - SW Infiltration
Investigation
Env Act (SODRP) investigation ongoing, Operational investigation ongoing
Improvement work
Operational improvement ongoing
Monitored since
2021
Water body
Team from Source to Tyne

This overflow spilled often enough to trigger the EA's high-spill review; the review line is the company's own stated reason.

Discharges we have recorded

577 discharge periods since 1 Jan 2021, 21 whose end the feed never gave. 533 of them come from Northumbrian Water's own event-duration-monitoring records (published on Stream, Jan 2021 – Dec 2024); this overflow has no live feed, so nothing after that log is held. The official annual count is the figure to quote.

Show 30 earlier (of 577)
StartedEndedDischarge time
2 h 29 min
37 min
2 h 24 min
29 min
1 h 1 min
18 min
46 min
2 min
not captured, before not captured
not captured, before not captured
1 h 53 min
1 h 6 min
1 min
not captured, before not captured
2 min
not captured, before not captured
2 min
not captured, before not captured
1 min
not captured, before not captured
2 min
not captured, before 0 min
2 min
1 min
not captured, before not captured
3 min
not captured, before not captured
not captured, before not captured
2 min
6 min

The year figures above use the EA's 12/24-hour counting method, so they are comparable with the official figures; the monitor log's 4,156 raw blocks were merged into 577 continuous discharge periods (gaps under 15 min joined).

Rain nearby last 30 days

Nearest live rain gauge: Rainfall gauge nr Stanley, 3.5 km away. Brown shading = when this overflow was discharging; ▼ = a discharge start.

Overflow shading is a timing match, not proof of cause — heavy rain and spills share a trigger. Times come from the water company’s event-duration monitor (site status only; no discharge volume is published).

Where it is

Nearest river gauge
Tanfield (River Team) · 0.2 km
Nearest rain gauge
Council area
County Durham
Site reference
NWL00487 · permit 235/1871
Coordinates
54.88842, -1.69815

Concerned about this overflow?

Report pollution you can see or smell to the regulator straight away; the company handles complaints about the overflow itself.

Write to the MP

The Environment Agency's return places this overflow in the North Durham constituency. An MP can ask the company and the regulator questions on a constituent's behalf. These words carry the official figures; change them as you like.

The link opens Parliament's own "Find your MP", which gives the MP's name and how to write to them. FloodRadar sends nothing and keeps nothing you write. Check the constituency against your own address: an MP acts only for people who live in it.

Annual spill figures: Environment Agency Event Duration Monitoring return, © Environment Agency copyright and/or database right, Open Government Licence (OGL) v3.0. Storm-overflow spill events: © the respective water company, published on Stream (data.streamwaterdata.co.uk) under CC BY 4.0. Discharges marked "via Top of the Poops", and this year's figures before 28 February, come from Top of the Poops' record of the same company feed, used under CC BY-SA 4.0: the feed's own start and end times as its pages print them, not their derived hours. Times are shown in UK local time. FloodRadar republishes the monitor's status and the EA's figures; it does not measure discharges itself. Constituency and council area from the EA's return: contains OS data © Crown copyright and database right 2026.