Sustainable Drainage Systems (SuDS)

Pilot schemes introducing Sustainable Drainage Systems (SuDS) are being launched in Fareham.

Phase 1: Westborn Road, Fareham

Start date: Monday 1 June 2026
Duration: Approximately nine to ten weeks
Permitted working hours: Monday to Friday, 7:30am–5:30pm (no noisy works before 8am)
The works were originally expected to be approximately 6 weeks; however, this has been extended due to the complications of installing the new drainage infrastructure around the significant number of existing services within Westborn Road, and the need to exercise additional care during excavations.

Traffic management

Westborn Road will be closed during construction for safety
Pedestrian and emergency access to all properties on Westborn Road will be maintained at all times
The pedestrian footpath link at the southern end of Westborn Road will be closed and a signed pedestrian diversion will be in place
Vehicle access may be restricted at times; the site team will work with residents to manage access where possible
Parking: temporary changes to parking and access will be managed during construction, and permanent parking restrictions will apply near the new raingarden once works are complete
Part of the nearby Palmerstone Avenue car park is planned for use as the site compound.

For the exact location and traffic management please visit Causeway One.network.

Please view the technical drawings:

Phase 2: Southampton Road and Serpentine Road

Phase 2A - Southampton Road and within the Harrison Primary School site and include:

Installing two new road drains and a connecting inspection chamber on Southampton Road
Installing a new underground pipe beneath the school driveway to connect the new road drains to the existing surface water sewer within the school grounds
Installing an underground rainwater storage system beneath the school driveway to help manage heavy rainfall
Resurfacing sections of the road and the school driveway following the works.

These works will disconnect existing road drains from the sewer system that currently carries both rainwater and wastewater. Rainwater from the road and nearby driveways will instead be directed into a separate rainwater sewer beneath the school site.

The existing underground rainwater storage system beneath the school driveway will hold water during heavy rainfall and release it slowly into the sewer network. This will help reduce pressure on the drainage system and lower the risk of it becoming overloaded during intense storms.

Traffic Management

The works are planned for the July/August 2026, during the school summer holidays
The specific Traffic Management details will be confirmed shortly
Vehicle access will be restricted at times; the site team will work with residents to manage access where possible
Temporary suspension of on-street parking spaces will be required to construct the works and minimise vehicle access disruption
Pedestrian and emergency vehicle access to all properties on Southampton Road will be maintained at all times.

Please view the technical drawings:

Further improvements are planned as part of Phase 2, with construction expected to take place in late 2026 or early 2027. More information will be published on this webpage as the plans are confirmed.

Hampshire County Council is working in partnership with Southern Water to deliver Sustainable Drainage Systems (SuDS) improvements in Fareham as part of a wider programme aimed at reducing sewer flooding and protecting local rivers and coastal waters.

Older combined sewers in the UK carry both household wastewater and rainwater in the same pipes. During heavy rainfall, large volumes of rainwater from roads, driveways and roofs enter the combined sewer network and these systems can quickly become overloaded. This increases the risk of waste water being released into rivers and the sea through combined sewer overflows (CSOs), to prevent flooding to homes and businesses.

Southern Water holds responsibility for managing waste water across the majority of Hampshire and it has a legal requirement to reduce CSO releases. Highway SuDS are a key part of Southern Water’s long term plan to reduce storm overflow releases by managing surface water more sustainably, alongside sewer upgrades and other improvements across the region. By capturing, slowing, and managing rainwater close to where it falls, the scheme will reduce pressure on the sewer network, decrease CSO events and improve environmental outcomes.

Hampshire County Council is working with Southern Water to reduce the amount of rainwater entering combined sewers from roads, homes, and other hard surfaces. This pilot introduces Sustainable Drainage Systems (SuDS) within public highways to support that goal. Fareham is a priority catchment for action under national environmental targets.

By slowing and managing rainwater from the highway and adjoining paved areas before it enters the sewer network, we can reduce CSO events and improve environmental outcomes. SuDS manage rainwater in a more natural and sustainable way by:

Temporarily storing water close to where it falls
Allowing gradual infiltration into the ground and evapotranspiration into the air
Slowing the flow into sewer systems

Benefits for the community and environment:

Lower risk of sewer flooding during heavy rainfall
Cleaner rivers and coastal waters
Reduced pollution entering the environment
Nature based drainage solutions that support biodiversity
More resilient infrastructure for future climate conditions

This partnership with Southern Water is a unique opportunity to deliver solutions that benefit both the environment and the local community. Please see further information from Southern Water is provided below:

More information on SuDS can be found at Southern Water’s website: Sustainable drainage solutions.

This pilot will deliver SuDS features within the highway at Westborn Road, Southampton Road and Serpentine Road, Fareham - including raingardens, new below-ground highway drainage features, and underground water storage. The raingardens will be constructed from kerbed and planted buildouts, with underground components to store and manage surface water.

These SuDS features will:

Capture and temporarily store rainwater close to where it falls
Slow the flow of water into sewer systems
Reduce pressure on the wider drainage network during storms.

Residents’ feedback during the early stages of the pilot has been considered during design and construction phase development, to minimise the impact on parking and access while still delivering the required storage and environmental benefits. Hampshire County Council and its contractor will engage with residents throughout construction of the pilot scheme across all sites to minimise disruption and manage access needs.

Southern Water and Hampshire County Council will monitor the performance of the schemes, and the results will help guide future decisions on expanding SuDS installations across Hampshire.

The new drainage assets will be adopted and maintained by the County Council as Highway Authority, with Southern Water funding future maintenance through commuted sums.

Delivery of the Phase 1 Pilot Scheme was formally approved under delegated authority by the Director of the County Council’s Universal Services directorate on 26 September 2025. Please read the Decision Report .

The associated changes to on-street parking were formalised. Please read the Decision Report.

Please read the FAQs MS (Sway document).

Southern Water is funding the design, construction, and maintenance of the SuDS features in this pilot. The project will test feasibility, effectiveness, and delivery processes, informing a broader strategy for future SuDS schemes across Hampshire.

Visit Causeway One.Network which is where the planned works are published and is an independent platform that allows real-time monitoring of all the UK’s roadworks and diversions.

My Journey - travel information and travel advice choices in Hampshire.

Name Highways, Engineering and Transport
Email [email protected]
Phone 0300 555 1388

Address
Universal Services
Hampshire County Council
The Castle
Winchester
SO23 8UD