Blocked highway drains
Bromley Council is responsible for around 35,000 highway drains (gullies) and their connections. Many of these connect to the public sewer network, which is maintained by Thames Water.
Planned drain cleaning
We clean highway drains through a planned maintenance programme.
Most drains are cleaned once every three years, although drains in areas that high risk for flooding may be cleaned more often.
To help overcome issues caused by parked vehicles, we will normally make up to two attempts to access and clean each drain during its scheduled maintenance cycle. Unfortunately, access may sometimes be blocked on both occasions. Where this happens, the drain will be attended again during its next scheduled visit.
Because of the large number of drains across the borough, we do not normally introduce temporary parking restrictions or road closures for routine cleaning works. However, where a separate reactive visit is required and access is essential, traffic management measures may be considered, subject to operational requirements and the necessary approvals.
If temporary parking restrictions are in place, we ask motorists to follow the signage provided. This helps us complete works safely and efficiently while minimising disruption.
Reported blocked drains
If you report a blocked drain, we aim to inspect it within five working days to determine whether further work is required.
During an inspection, we will typically check:
- Whether the gully pot is clear
- Whether the outlet is visible
- Whether water can flow through the drainage system
Some drainage issues can only be properly assessed during wet weather, which may mean further investigation is needed before a decision can be made.
How we prioritise work
Reactive drainage work is prioritised according to whether it is assessed as being in a ‘critical location’.
A drain may be considered as being in a critical location if its condition is likely to cause:
- Flooding to nearby properties, or
- Significant standing water, and
- There are no nearby working drainage assets available to take the excess water.
A drain may be considered as being in a non-critical location where:
- Flooding or significant ponding is unlikely, or
- Other nearby drains are able to manage the additional water flow.
Where a planned maintenance visit is due in the near future, a separate reactive visit may not always be necessary.
Non-critical drains will normally be flagged for attention during the next scheduled maintenance visit.
Complex drainage issues
Some drainage problems can take longer to identify and resolve.
Additional investigations may be required, including:
- CCTV surveys of the drainage system
- Specialist drainage investigations
- Involvement from other organisations, such as Thames Water
It is important to note that standing water does not always mean a drain is blocked. Water can collect temporarily because:
- The road surface naturally slopes or dips
- Heavy rainfall exceeds the drainage system's capacity
- Water is draining away more slowly than usual
Reporting the correct problem
If leaves, litter or other debris are covering the top of a drain grate, please report this as street sweeping rather than Blocked Drain. This allows the street cleansing team to respond appropriately, rather than initially handling the report as a blocked gully and thus delaying corrective action.
The blocked drain category should be used where:
- The blockage appears to be inside the drain, or
- Water is not draining away as expected.
Manual dig-out works
Some drains contain compacted silt or debris that cannot be removed using standard cleansing equipment.
In these cases, a manual dig-out may be required.
At non-critical locations, these works are normally grouped together and completed as part of a planned programme to make best use of resources and minimise disruption.