GEOTECHNICAL, DRAINAGE & SUDs

Geotechnical Site Investigation

We can scope and supervise appropriate geotechnical ground investigation to match the requirements of the proposed development. Ground investigation aims to collect all necessary geotechnical information related to underlying soil/rock/groundwater conditions to allow for geotechnical and structural design calculations.

Investigation will be carried out in accordance with relevant British Standards. Geotechnical purposes are often combined with required elements of a Phase 2 Contaminated Land Site Investigation to maximise the amount of information obtained.

Coal Mining Risk Assessment

In accordance with UK planning guidance, all sites identified by the Coal Authority as being within a Development High Risk Area must undergo a Coal Mining Risk Assessment (CMRA) as part of planning consent. The purpose of a CMRA is to report on a desk-based & site walkover review of all available information on the coal mining legacy relevant to the site, to assess potential risks and to propose further investigation or mitigation measures to address any such arising.

Soakaway Drainage Design & Testing

To scope and supervise soakaway design and testing assessments in accordance with BRE 365, to establish whether a soakaway drainage system is suitable for your site.

SUDs (Sustainable Urban Drainage schemes)

SUDs are an approach to managing rainwater falling on roofs and other surfaces through a
sequence of actions. The key objectives are to manage the flow rate and volume of surface runoff to
reduce the risk of flooding and water pollution. SUDS also reduce pressure on the sewerage network
and can improve biodiversity and local amenity.

DEFRA (2011)

SUDs control surface water runoff with the intention of replicating natural site drainage as a strategy to control and reduce the impacts of flood risk downstream under current and forecast future climate scenarios. SUDs can also remove pollutants from urban runoff at source.

Options appraisal for SUDs is now expected for all new developments. The order of preference for surface water runoff management is as follows:

1. Discharge to the ground
2. Discharge to a surface water body
3. Discharge to a surface water sewer or local highway drain
4. Discharge to a combined sewer

SUDs designs for new developments are required to be reviewed by the local SUDs approval board, which is usually the County Council in their role of Lead Local Flood Authority. However, submission should in the first instance proceed through the ordinary planning process administered by the Local Planning Authority