Drainage and Private / Adoptable Highway Design
Civilistix Consulting Engineers were appointed to initially discharge drainage and external hardstanding planning conditions and subsequently, prepare the detailed private and adoptable civils design including Highway S278/S38 and Drainage S104/S106 technical approval packages for a 25-unit residential scheme and associated infrastructure.
We prepared a surface water drainage design which proposed a significant portion of permeable paving to private external hardstanding areas as well as large geo-cellular tank which together provided the required attenuation for the scheme whilst adhering to the Internal Drainage Boards extremely tight discharge rate of 1.1 l/s to their receiving watercourse.
We worked with Anglian Water early on to ensure the geo-cellular storage tank would be suitable for full adoption (under S104 of the Water Industry Act) considering the recently released Design Construction Guidance (DCG) providing greater onerous of sewerage undertakers to adopt SuDS structures.
Due to site levels and shallow public sewers within vicinity of the site, we proposed foul water from the development to be collected via carrier pipes operating via gravity before discharging to a Type 3 foul water pumping station before connecting via rising main to an existing foul water sewer.
Further to onsite works our scope also included for preparation of an offsite S278 design package to widen an exisitng public highway to accommodate development proposals.