Plan around the site and intended use
New drainage needs a clear understanding of what it will serve, the available levels, connection points, ground conditions and any constraints around buildings or other services.
Foul and surface-water systems
Foul drainage and rainwater management have different requirements. Surface-water options may include appropriate collection, attenuation or infiltration measures, subject to the site conditions and the relevant design and approval route.
A soakaway is not suitable simply because space appears available. Ground conditions, separation distances, runoff volume and maintenance access need to be considered before a solution is selected.
Information for a useful enquiry
Drawings, planning information, survey levels and the proposed use of the property help define the work. For managed or commercial sites, include operating constraints and the people who need to approve access or shutdowns.