A Construction Management Plan (CMP) should be provided to ensure that during construction the drainage network and surrounding environments are not impacted negatively.
|What the LLFA expect to see
A construction management will usually be conditioned. When applying to discharge this condition, a document highlighting how surface water will be managed during construction and how pollution is mitigated against should be provided. Within this it should highlight how the drainage scheme and SuDS features are to be built as early on as possible and that they will be flushed and restored to their full working order at the end of construction.
A construction management plan (CMP) is most commonly asked for at the discharge of conditions stage. Any scheme should ensure that appropriate mitigation procedures are in place to limit the impact of construction works on off-site flooding through surface water run off or on ground water. If left unmanaged the removal of topsoil prior to construction may result in excess water being discharged from site.
The drainage scheme should be implemented as early on as possible in order to ensure surface water is managed throughout not only the life time of the development but also the life time of the construction. An exception to this should be the installation of permeable paving. Permeable paving should be constructed towards the end to maintain its porosity and structural integrity.
Unless temporary drainage solutions are provided during construction, all drainage features and SuDS features should be fully maintained and restored to their full intended working capacity. This includes processes such as removing all sediment build up that may have occurred during construction. Care should be used in order to not remobilise these and flush them into the water system. Care should also be taken to minimise the compaction of any soil during construction particularly when infiltration is relied upon to manage surface water on site.
Page updated: 5/02/2020