Hawthorn Park, Leominster

Flood Prevention

SDS stormwater management system ensures new housing development is flood risk free

Overview

Hawthorn Park is a new residential development in Barons Cross, Leominster, comprising 353 homes, including 88 affordable units. Delivered by Persimmon Homes with groundworks by Bell Contracting, the 12-hectare brownfield site was previously a turkey farm and military hospital. The development incorporates green infrastructure, recreational spaces, and sustainable drainage to create a resilient, environmentally responsible community.

SDS was appointed to provide a stormwater attenuation system to manage surface water runoff and ensure the site remains flood risk free, while meeting planning and environmental compliance requirements.

What We Did

SDS supplied and installed a GEOlight® attenuation tank with 1,890m³ capacity, supported by a 1,500mm diameter Weholite manhole, alongside main pipework including perforated and unperforated sections with couplers and ring seals. The tank is located within a retention basin, giving total storage of 2,511m³—sufficient to safely manage a 1 in 100 year +40% storm event.

The system was designed to Sewers for Adoption 7th edition standards and can be adopted and maintained as an offline system under an S104 agreement by Dwr Cymru Welsh Water. SDS coordinated closely with the project team to ensure integration with wider green infrastructure and compliance with nutrient-neutrality measures.

Results

The SDS attenuation system provides reliable, policy-compliant surface water management for the Hawthorn Park development. It reduces flood risk, protects downstream watercourses including the Rivers Lugg and Wye SACs, and supports environmental objectives such as biodiversity enhancement and nutrient neutrality.

The system ensures long-term operational resilience, allowing safe management of stormwater during extreme rainfall, while complementing wider sustainability measures, including low water-use fittings throughout the new homes.