The North Portsea Coastal Scheme is celebrating a major milestone in environmental restoration and heritage enhancement, with additional dedicated environmental funding secured for 2025/26. Work to improve water quality of the adjacent Hilsea moat is set to start this week.

The funding is enabling a wide range of improvements that go far beyond flood protection, including:

• Water quality improvements
• Preservation of historic moats
• Habitat creation such as saltmarsh at intertidal zones
• Biodiversity improvements aligned with sustainable flood risk management

As the final phase of the scheme progresses at Ports Creek in Hilsea, focus has turned to the adjacent Hilsea Moat – a historic and ecologically rich feature within the Hilsea Lines area, locally known as Foxes Forest.

Part of the historic Hilsea Lines fortifications, the moat is also a vital green corridor supporting wetlands, reed beds, and woodland. However, it faces environmental challenges including algal blooms, silt build-up, and fluctuating salinity. These can be deadly to the animals inhabiting these moats.

To address these issues, work beginning from end of September 2025 will include:

• Dredging to restore water depth and reduce temperature and salinity variations
• Reedbeds to trap nutrients
• Marginal edging to hold dredged material whilst restoring eroded moat banks to their original form and providing space for additional planting and refuges for fish and eels

The Hilsea Lines is designated as a Scheduled Monument. All works are being delivered in collaboration with Historic England. Scheduled Monument Consent has been granted for delivery of the coastal defence scheme and moat improvement works.

These enhancements are in addition to those being incorporated across the flood defence scheme, including a heritage interpretation strategy, bird boxes, bat boxes, kingfisher tunnels, beetle loggeries, and wildflower planting.

Amy Conway, Project Delivery Manager  says: “This is a shining example of how we can protect our heritage and restore nature all at once whilst delivering a future proof flood defence scheme.

The area around Hilsea Lines is a hidden gem in Portsmouth, and our work, together with these improvements will help it thrive for generations to come – benefiting wildlife, residents, and the wider environment.”

Dredging starts this week and all moat improvement work is scheduled for completion by the end of 2025. Specialist plant, including an amphibious excavator, will work from inside the existing site boundary, so no extra path closures will be needed. The initial dredging will disturb some long‑settled silt and may produce a temporary odour; this will disperse naturally and is not a cause for concern.

At the heart of this work is a dedicated environment team – a group of passionate professionals who care deeply about nature and the local community. Their commitment is driving forward a vision where flood protection, biodiversity, and heritage go hand in hand.