Environmental services aims

Bromley Council are responsible for highway gullies and their connections to the surface water public sewage system. There are approximately 35,000 roadside gullies under our responsibility. The surface water public sewage system itself is the responsibility of Thames Water.

We undertake a cyclic clean of all our highway drainage assets including roadside gullies. The majority are attended on an every other year basis, but assets in areas which have been identified at higher risk of flooding are programmed as often as three times per year.

Under this cyclic programme, assets are attempted twice. Because of the number of assets under our responsibility, where access is prohibited on both of those occasions, and the drain is in a non-critical location or no surface flooding is presenting, we will attempt again on the next cyclical visit. In some instances, particularly where the asset is in a critical location, we may arrange temporary parking restrictions or road closures to carry out the works. Such restrictions must be co-ordinated and scheduled and cannot be undertaken upon request. Please do not park your vehicle where ‘no parking’ signs have been displayed as this will hinder and delay works.

‘Critical location’ gullies are defined as those which would contribute to or cause flooding of nearby property, or contribute to or cause excessive surface water pooling, and there are no downstream or nearby operational drainage assets which are capable of taking the increased flow. ‘Non-critical location’ gullies are defined as those which would not contribute or cause flooding of nearby properties, or do not contribute nor cause excessive surface water pooling, and there are downstream or nearby operational drainage assets that are capable of taking the increased flow.

Where specific issues, such as individual blocked drains, are reported, we aim to inspect within five working days to decide whether work needs to be to be undertaken. Typically, we assess whether the gully pot is clear, if the outlet is visible, and/or whether water is flowing. Some drainage issues can only be assessed in wet conditions which may delay our response. Subsequent arrangement of reactive (ad-hoc) work will be dependent on whether the gully is determined to be in a critical location. We may not arrange reactive work when a scheduled cyclical attendance is forthcoming, balanced with the criticality of the location in question.

Complex or less obvious drainage issues can take longer to resolve and may require investigation with CCTV and/or third party involvement to establish where in the drainage infrastructure a blockage has occurred.

Pooling water can also be a result of natural gradients and road camber and may not be due to blockages within the drainage system itself. Other times it may be because the capacity of the drain is smaller than the volume of water, which will mean it simply drains more slowly. Where such issues exist within the council’s inventory, consideration may be given to including the location on our forward drainage works plan.

Debris on top of the gully grate will be referred to our street cleansing service provider for attendance. Therefore, when considering raising a new report for a ‘Blocked drain’, please try to distinguish whether it is blocked only on the surface or inside the gully pot itself as this will help us to be more guided in our initial response. If it is a surface blockage with detritus, please raise a report under the ‘Street sweeping’ category rather than ‘Blocked drain’.

Assets that are compacted with silt and detritus which ordinary equipment cannot dislodge will require a manual dig-out. These are undertaken in bulk for efficiency, rather than individually, where the gully is in a non-critical location. These are added to a forward works programme and attended in due course.