Coldharbour Lane Pumping Station

Storm overflow run by Southern Water, discharging into Tributary Of The Hilden Brook.

Storm discharge at pumping station Tonbridge constituency
Right now
No live feed
Southern 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
38spills
at least 516 h discharging on 38 days · counted by us, not yet official · 1 discharge whose end the feed did not report (counted, no hours)
2025 official
44spills
521 h · −51% on 2024
Rank in Southern Water
#95
of 970 overflows by 2025 spills (1 = most)
Monitor in 2025
99.9% working
Long-term average 66.9 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 Southern Water's monitor log. 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.

2021
80 spills · 1,569 hmonitor 100%
2022
47 spills · 592 hmonitor 100%
2023
90 spills · 1,254 hmonitor 99.8%
2024
89 spills · 1,211 hmonitor 99.2%
2025
44 spills · 521 hmonitor 99.9%
2026so far
38 spills · at least 516 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.

What the 2025 return says

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

High-spill review
Performance - GW inundation
Investigation
Env Act (SODRP) investigation ongoing, UWWTR investigation ongoing
Improvement work
No improvement action in reporting period
Monitored since
2016
Water body
Hilden Brook

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

60 discharge periods since 15 Jun 2024, 1 whose end the feed never gave. 58 of them come from Southern Water's own event-duration-monitoring records (from its Rivers and Seas Watch service, Jun 2024 – Sep 2026); 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 60)
StartedEndedDischarge time
1 d 9 h
1 d 4 h
2 d 23 h
2 d 4 h
1 d 9 h
15 h 47 min
1 d 18 h
2 h 50 min
16 h 45 min
1 d 2 h
16 h 42 min
6 h 32 min
11 h 51 min
3 h 31 min
4 h 54 min
4 h 15 min
3 h 32 min
2 h 16 min
1 h 40 min
1 h 0 min
2 h 33 min
1 h 17 min
1 d 7 h
1 d 17 h
21 h 31 min
2 d 12 h
1 d 7 h
3 d 1 h
1 d 10 h
22 h 41 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 64 raw blocks were merged into 60 continuous discharge periods (gaps under 15 min joined).

Rain nearby last 30 days

Nearest live rain gauge: Rainfall gauge nr Sevenoaks, 2.7 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
Nearest rain gauge
Council area
Tonbridge and Malling District (B)
Southern Water's own name for it
Coldharbour Lane Hildenborough CEO - 108613
Site reference
SWS00190 · permit A01475
Coordinates
51.21757, 0.25096

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 Tonbridge 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.

Find the MP for Tonbridge

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. Spill-event history: Southern Water's Rivers and Seas Watch release history (riversandseaswatch.southernwater.co.uk), © Southern Water. Shown by FloodRadar: only releases Southern Water marks Genuine and that have ended; those it marks Not Genuine or still has under review are left out. 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.