River Mole Conditions
River level, flood, sewage overflow and recent water quality information for Leatherhead, Box Hill and nearby River Mole locations
River Mole live level overview
This page combines Environment Agency river level gauges around the River Mole. Levels are normally monitored around every 15 minutes, but public updates may vary by site and increase during flood risk periods.
River levels: cached for 15 minutes • Thames Water overflow monitoring: cached for 10 minutes • River Watch reports: checked daily
River levels: cached for 15 minutes • Thames Water overflow monitoring: cached for 10 minutes • River Watch reports: checked daily
Flood alerts: No River Mole flood alerts found
Leatherhead
River Mole through Leatherhead and Fetcham
1.27m
Normal — Steady
| Last EA reading | 09:30, 11 Jun 2026 |
| Normal low | 1.00m |
| Normal high | 2.61m |
| Max on record | 3.73m |
Dorking / Box Hill
Closest upstream gauge for Box Hill and Stepping Stones
0.14m
Normal — Steady
| Last EA reading | 09:30, 11 Jun 2026 |
| Normal low | 0.09m |
| Normal high | 1.60m |
| Max on record | 2.73m |
Downside Bridge / Cobham
Downstream of Leatherhead towards Cobham
1.08m
Normal — Steady
| Last EA reading | 09:30, 11 Jun 2026 |
| Normal low | 1.01m |
| Normal high | 2.70m |
| Max on record | 3.46m |
Esher
Lower River Mole before the Thames
1.48m
Normal — Steady
| Last EA reading | 09:30, 11 Jun 2026 |
| Normal low | 1.27m |
| Normal high | 4.32m |
| Max on record | 3.24m |
About these river level locations
Leatherhead is the main local gauge for the town, Fetcham and the nearby riverside paths. Dorking / Box Hill is the best nearby upstream indication for Box Hill and the Stepping Stones area. Downside Bridge / Cobham helps show what is happening downstream after water has passed Leatherhead. The Dorking gauge has more than one EA level measure, so this page uses the normal river stage reading rather than the downstream stage value that can appear as a negative number.
These locations refer to the river level tiles above. For safety decisions, always follow official Environment Agency flood warnings and local advice. River paths, stepping stones and low-lying roads can become unsafe even when wider property flooding is not expected.
Data source: Environment Agency flood and river level data from the real-time data service.
Leatherhead river conditions
River level1.27m
Level statusNormal — Steady
Sewage overflow status🟢Clear
Most recent overflow activity2 Jun 2026, 04:45 to 3 Jun 2026, 01:00
This featured box combines the Leatherhead river level with the Leatherhead storm-overflow status. The overflow status does not prove the river is clean or safe.
Water quality and sewage overflow information
This section separates two different things: live sewage overflow signals from Thames Water, and wider water-quality reports from River Mole River Watch. The Thames Water data tells us whether monitored overflows are currently active or have recently operated; it does not test the river water itself.
Important: River level data is live/near-live. Thames Water sewage overflow data is also current, but it only shows whether a monitored overflow has discharged. It does not measure bacteria, chemicals, smell, sewage solids or whether the river is safe for people or dogs.
River Mole sewage overflow monitoring
Live data checked
09:56, 11 Jun 2026
This section shows reported storm-overflow activity on, or close to, the River Mole catchment. Green means no active discharge is currently reported, amber means recent activity, and red means a discharge is currently reported. This does not measure bacteria, chemicals or whether the river is safe for people or dogs.
🟢 No active sewage discharges currently reported on the listed River Mole sites.
ClearLeatherhead
Last activity: 2 Jun 2026, 04:45 to 3 Jun 2026, 01:00
Last activity: 2 Jun 2026, 04:45 to 3 Jun 2026, 01:00
0Currently discharging
2Locations with activity in the last 7 days
14Sites monitored
Most recent recorded overflow activity:
- Box Hill — Groundwater: Ended 10 Jun 2026 20:45 (13 hours ago)
- Dorking Road — Buckland Brook: Ended 4 Jun 2026 21:00 (6 days ago)
- Horley (Surrey) — River Mole: Ended 3 Jun 2026 07:15 (8 days ago)
- Leatherhead — River Mole: Ended 3 Jun 2026 01:00 (8 days ago)
About sewage monitoring
This table shows whether monitored Thames Water storm overflows have recently discharged into the River Mole catchment. River / Stream affected means where water from an overflow is reported to enter the environment. This may be the River Mole itself, one of its smaller tributaries, a brook, a ditch or, at some sites, groundwater.
This information does not measure bacteria, chemicals, smell, sewage solids or whether the river is safe for swimming, paddling or dogs.
This table shows whether monitored Thames Water storm overflows have recently discharged into the River Mole catchment. River / Stream affected means where water from an overflow is reported to enter the environment. This may be the River Mole itself, one of its smaller tributaries, a brook, a ditch or, at some sites, groundwater.
This information does not measure bacteria, chemicals, smell, sewage solids or whether the river is safe for swimming, paddling or dogs.
| Location | River / Stream affected | Status | Last activity | Latest start | Latest stop |
|---|---|---|---|---|---|
| Leatherhead | River Mole | 🟢Clear | Ended 3 Jun 2026 01:00 (8 days ago) | 04:45, 2 Jun 2026 | 01:00, 3 Jun 2026 |
| River Lane | River Mole | 🟢Clear | Ended 21 Jan 2026 19:45 (140 days ago) | 18:30, 21 Jan 2026 | 19:45, 21 Jan 2026 |
| Stoke Road, Cobham | River Mole | 🟢Clear | Ended 26 May 2026 15:50 (15 days ago) | 22:32, 24 May 2026 | 15:50, 26 May 2026 |
| Cobham Bridge, Adj Cobham PS | River Mole | 🟢Clear | Ended 21 May 2026 07:30 (21 days ago) | 06:45, 21 May 2026 | 07:30, 21 May 2026 |
| Esher | River Mole | 🟢Clear | Ended 17 Feb 2026 02:15 (114 days ago) | 07:15, 16 Feb 2026 | 02:15, 17 Feb 2026 |
| Dorking Road | Buckland Brook | 🟢Clear | Ended 4 Jun 2026 21:00 (6 days ago) | 08:30, 3 Jun 2026 | 21:00, 4 Jun 2026 |
| Dorking | River Mole | 🟢Clear | Ended 10 Feb 2026 03:30 (121 days ago) | 17:45, 5 Feb 2026 | 03:30, 10 Feb 2026 |
| Castle Gardens, Dorking | River Mole | 🟢Clear | Ended 27 Jan 2026 15:00 (134 days ago) | 07:45, 27 Jan 2026 | 15:00, 27 Jan 2026 |
| Brockham Bridge | River Mole | 🟢Clear | Ended 21 May 2026 10:45 (20 days ago) | 10:15, 21 May 2026 | 10:45, 21 May 2026 |
| Stonebridge SSO, Brockham | River Mole | 🟢Clear | Ended 2 Jun 2026 07:00 (9 days ago) | 06:30, 2 Jun 2026 | 07:00, 2 Jun 2026 |
| Box Hill | Groundwater | 🟠Recent discharge | Ended 10 Jun 2026 20:45 (13 hours ago) | 19:45, 10 Jun 2026 | 20:45, 10 Jun 2026 |
| Horley (Surrey) | River Mole | 🟢Clear | Ended 3 Jun 2026 07:15 (8 days ago) | 18:45, 2 Jun 2026 | 07:15, 3 Jun 2026 |
| Ironsbottom (Sidlow) | Tributary of River Mole | 🟢Clear | Ended 17 Feb 2026 05:45 (114 days ago) | 02:30, 17 Feb 2026 | 05:45, 17 Feb 2026 |
| Crawley | Tributary of River Mole | 🟢Clear | Ended 16 Feb 2026 04:00 (115 days ago) | 16:45, 15 Feb 2026 | 04:00, 16 Feb 2026 |
A clear status only means the listed overflow is not currently reporting an active discharge. It does not mean the River Mole is clean or safe.
River Mole River Watch water quality update
Cached 24 hours
Updated 3 May 2026
Showing: River Mole River Watch - April 2026 update.
This River Watch section is checked and cached locally once every 24 hours. It is a recent water-quality summary, not a live pollution reading.
River Mole River Watch - April 2026 update
Poor phosphate pressure
Updated 3 May 2026
April 2026 was exceptionally dry. River Mole River Watch reported that low river flows allowed pollution concentrations to strengthen, with catchment mean phosphate rising to 0.62 mg/L and the highest proportion of Poor/Bad phosphate results so far in 2026.
- April showed no recorded river storm overflow discharges to the Mole or its tributaries in the main dataset.
- Box Hill EDM recorded around 7 hours of discharge to groundwater on 26 April after a long dry spell.
- Stepping Stones nitrate rose strongly in April, reflecting the low-flow concentration issue.
River Mole River Watch - March 2026 update
Bad catchment status
Updated 13 Apr 2026
The March update reported the catchment returning to overall Bad water quality status after three months of Moderate condition. River Mole River Watch also launched monthly E.coli testing on Earlswood Brook.
- Phosphate, nitrate and conductivity all rose compared with February.
- A third of sites reported Poor or Bad results in March.
- Leatherhead was highlighted in relation to high storm overflow duration from January to March.
Thames Water storm discharge map
Near real-time EDM
Updated by Thames Water / Water UK feeds
Thames Water publishes near real-time Event Duration Monitoring data. EDM can indicate when storm overflows are currently discharging and the date, time and duration of the last recorded discharge.
- EDM indicates overflow activity; it does not directly test water quality or bacteria levels.
- A clear EDM status does not prove the river is safe for swimming, paddling or pets.
- Use the official map for the latest live storm overflow position.
Official EA classification - background only
These official classifications are useful background for the long-term health of the river, but they are retrospective. They should not be read as today’s pollution level or as a real-time safety check.
Mole - Dorking to Leatherhead: Official Catchment Data Explorer water-body classification for the Box Hill / Stepping Stones area. Useful background, but not current pollution monitoring. Open EA page
Mole - Leatherhead to Hersham: Official Catchment Data Explorer water-body classification for Leatherhead and the downstream River Mole. Useful background, but not current pollution monitoring. Open EA page
Safety note: Please do not treat this page as a swimming, paddling or dog-safety clearance. River water can be polluted even when no overflow is currently active, especially after rain, because runoff, drains and older discharge events can still affect water quality.