The following work has been carried out by the Highways Agency to clear culverts and drains between Junctions 8-11A of the M5 during the course of the last year:
All gully outlets between Junctions 8 and 9 and the outfalls of all gullies have been tested between Junctions 9 and 11a, to ensure that water drains away satisfactorily.
Renewal and replacement of sections of filter material in French drains to allow satisfactory discharge of run-off from carriageways between Junctions 8 and 11.
Cleaning of central reservation chambers/drainage pipes, over a distance of eight miles.
Visual inspections of large culverts beneath the M5 between Junctions 8 and 11a. Silt cleaned from culvert at M5 J11a with CCTV surveys of smaller drains to ascertain their condition.
Removal of root infestation from drainage pipes identified from CCTV survey, over a distance of 0.7 miles.
Repairs to remove defects to drainage pipes identified by CCTV survey at M5 between Junction 9 and 10.
Vegetation clearance and re-profiling of ditches, over a distance of 17 miles.
The information collected has been collated and is now included in an asset inventory. This is being reviewed to identify additional maintenance needs at identified vulnerable sites.
The maintenance requirements of the culverts and drains are monitored regularly. The Highways Agency will continue with its cyclical maintenance activities including gully cleaning, cutting vegetation in the ditches, keeping outfalls and gullies clear of debris. Additional drainage defect repairs are programmed between Junction 11A and 11, together with filter drain stone replacement, further ditch vegetation clearance and excavation of ditches following winter vegetation clearance.