Balder Catchment (trib of Tees) sewage map and spill data

3 storm overflows listed in the 2025 annual return name this water. All are operated by Northumbrian Water. Check the latest company report for each outlet below.

3
Outlet records: 186
Spills in 2025: 2,229
Recorded hours: 3
Linked to a live feed

2 records show monitor operation below 90%. Annual figures describe the whole of 2025, not today.

Official waterbody record ↗How spills are counted Search the national map

Outlets on Balder Catchment (trib of Tees)

Filter by the latest company report. The map follows the filters.

Filters apply to the map and list. Recent stops need a current report and a recorded stop time. They do not show whether water is safe.

Showing 3 of 3 outlets

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Balder Cottage CSO
Northumbrian Water · River Balder
Current status unknown
2025 annual record:0spills0hours

Cotherstone STW
Northumbrian Water · River Balder
Current status unknown
2025 annual record:161spills2,196.5hours
The Hagg CSO
Northumbrian Water · Tributary of River Balder
Current status unknown
2025 annual record:25spills32.7hours

Most recorded spills in 2025

The highest 2025 counts among these outlets. A count is events, not volume or harm. Equal counts share a rank.

1
Cotherstone STW
Northumbrian Water
161spills
2
The Hagg CSO
Northumbrian Water · monitor coverage 86.9%, below 90%
25spills
3
Balder Cottage CSO
Northumbrian Water · monitor coverage 75.1%, below 90%
0spills

Spills over time

The median outlet on Balder Catchment (trib of Tees) recorded 25 spills in 2025, against 11 across England.

1 outlet has a comparable count for both 2024 and 2025, with the monitor working at least 90% of each year. 0 recorded more spills, 1 fewer and 0 the same. Together it went from 228 to 161 spills, a fall of 29%.

Year	Outlets with a count	Total spills	Median per outlet	England median
2025	3	186	25	11
2024	3	273	45	19
2023	1	223	223	20

Earlier returns list fewer of these outlets, so totals are not comparable between years. The median per outlet and the like-for-like change are fairer comparisons. Counts are events, not volume.

All outlet records on Balder Catchment (trib of Tees)

3 outlet records in alphabetical order. Each link opens the outlet page with its latest report and annual history.

Balder Cottage CSORiver Balder · 0 spills in 2025
Cotherstone STWRiver Balder · 161 spills in 2025
The Hagg CSOTributary of River Balder · 25 spills in 2025

Sources and dates

Outlet locations, waterbody links and spill figures come from the Environment Agency 2025 event duration monitoring annual return. The latest company reports come from each operator’s live feed and carry their own dates. Waterbody ID: GB103025072240. The official waterbody record is a source lookup; its classification is not imported here.

All sources How the data works Report pollution

Questions about Balder Catchment (trib of Tees)

Which outlets are linked to Balder Catchment (trib of Tees)?: The source links 3 outlet records to waterbody GB103025072240. The link comes from the annual return; it does not model where a discharge travelled.
How many spills were recorded for Balder Catchment (trib of Tees)?: 3 records report 186 spills in 2025 and 2,229 recorded hours. All listed records have a usable count. Outlets can discharge at the same time, so the hours are not the time the whole water was affected.
Who is responsible for the outlets on Balder Catchment (trib of Tees)?: Northumbrian Water operates every listed outlet. Contact the operator or the official pollution service if you see a problem in the water.
Which outlets on Balder Catchment (trib of Tees) are linked to a live feed?: 3 of the 3 records are matched to a monitor in a company live feed. A link does not mean the monitor is working now. Use the status filters above to see the latest report for each outlet, with its date. The rest show annual figures only.
How complete is the monitoring for Balder Catchment (trib of Tees)?: 2 of the listed records have monitor operation below 90% for 2025. Events can be missed when a monitor is not working, so low counts from those outlets may understate activity.
Does this show if Balder Catchment (trib of Tees) is safe?: No. Event duration data does not measure bacteria, chemicals or current water quality. Use official local water-quality advice for that question.