Marshall Close CSO - Barnham

Storm overflow run by Southern Water, discharging into Barnham Rife.

Storm overflow on the sewer network Arundel and South Downs constituency
Right now
Not discharging
Last discharge ended on (1 day ago).
Times are UK time. Company feed updated 3 min ago

"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
59spills
at least 767 h discharging on 60 days · counted by us, not yet official · 10 discharges whose end the feed did not report (counted, no hours)
2025 official
71spills
434 h · −43% on 2024
Rank in Southern Water
#24
of 970 overflows by 2025 spills (1 = most)
Monitor in 2025
100% working
Long-term average 64.4 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 and the live 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.

2021
14 spills · 140 hmonitor 100%
2022
57 spills · 983 hmonitor 99.9%
2023
137 spills · 1,926 hmonitor 99.7%
2024
124 spills · 1,150 hmonitor 100%
2025
71 spills · 434 hmonitor 100%
2026so far
59 spills · at least 767 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
Not asset maintenance - Hydraulic capacity
Investigation
Env Act (SODRP) investigation ongoing, UWWTR investigation ongoing
Improvement work
No improvement action in reporting period
Monitored since
2016
Water body
Lidsey Rife

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

1,211 discharge periods since 15 Jul 2024, 10 whose end the feed never gave. 1,187 of them come from Southern Water's own event-duration-monitoring records (from its Rivers and Seas Watch service, Jul 2024 – Mar 2026); the live feed adds anything after that. The official annual count is the figure to quote.

Show 30 earlier (of 1,211)
StartedEndedDischarge time
not captured, before 29 min
3 min
not captured, before not captured
7 min
1 h 7 min
not captured, before not captured
not captured, before not captured
6 min
13 min
19 min
19 min
4 h 41 min
4 h 22 min
7 h 2 min
1 h 1 min
15 min
12 min
2 min
1 h 3 min
1 h 37 min
3 h 49 min
3 min
1 h 37 min
2 min
3 min
5 h 5 min
3 min
5 h 29 min
2 min
3 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 8,366 raw blocks were merged into 1,211 continuous discharge periods (gaps under 15 min joined).

What the feed showed

FloodRadar's own record of every change of state Southern Water's live feed has shown for this overflow, kept since : 43 states. The feed publishes its status now and its latest discharge, nothing older; the discharges above are read from this. It is here so the figures can be checked.

Show the last 40 states
SeenStatusSinceLatest discharge
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Discharging → no end yet
Discharging → no end yet
Discharging → no end yet
Discharging → no end yet
Discharging → no end yet
Discharging → no end yet
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Discharging → no end yet
Discharging → no end yet
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Not discharging →
Discharging → no end yet
Not discharging →
Not discharging →

Rain nearby last 30 days

Nearest live rain gauge: Rainfall gauge nr Fontwell, 3.2 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
Barnham (Barnham Rife) · 0.1 km
Nearest rain gauge
Council area
Arun District
Southern Water's own name for it
Marshall Close Barnham CSO - 108037
Site reference
SWS00557 · permit A01121
Coordinates
50.83006, -0.63937

Tell me when this overflow discharges

One message when the company's monitor reports a new discharge here. At most one every 6 hours.

Setting this alert needs JavaScript. The alerts you already have are on your alerts page.

The alert repeats the monitor's status: whether the overflow is discharging, not how much or why. It can only tell you about a discharge that starts after you turn it on.

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 Arundel and South Downs 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.

Live status: © Southern Water storm overflow activity data, licensed under CC BY 4.0. 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. Discharges marked "via Top of the Poops", 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.