The South Downs and Harbours pathfinder project
Pan Parishes, Hampshire
Why a pathfinder here?
There is excess groundwater in the area which find its way into the sewer system through leaking joints in public and private sewers. When the ground water is high tankers are deployed which impacts the residents. If the level gets very high, there is a need to release excess water to a local watercourse. These events are similar to storm overflows. The root cause therefore leading to spill events is different to the other catchments. Finding solutions that work in this catchment can inform similarly affected villages/towns in the future across our region. This project is trialling new engineering analysis, techniques, and technologies.
Stage of the project - In delivery
We’re relining the public sewers (owned by Southern Water) in the area, sealing private household pipework using a new innovative chemical called Tubogel, and we have commissioned a feasibility study for the creation of a wetland which would capture all excess flows. We've also installed 30 temperature sensors and drilled three new boreholes so we can understand the relationship between sewer levels and groundwater depth.
Timings
Work is ongoing and dependent on the groundwater levels in the area. Aiming to be complete by March 2025.
Desired outcome
Implement interventions to significantly reduce the need for tankers and pumping in the area.
Plans on a page
Potential Wetlands schemes
Reports
Pan Parishes Infiltration Reduction Plan
Case Studies
Sustainable drainage systems to slow the flow in schools across the south
Tubogel to reduce groundwater infiltration
More information
Constructed Wetlands
Bosham, West Sussex
Why a pathfinder here?
There is excess groundwater in the area which find its way into the sewer system through leaking joints in public and private sewers. This is causing the local storm overflow to frequently activate.
Stage of the project - feasibility
We've studied the area and considering the best solutions to implement in the catchment.
Timings
This is to be confirmed
Desired outcomes
Reduce storm overflows and flooding, impacting the Chichester Harbour area.