More about the Slea Flood Resilience Project

The River Slea is a 36km-long tributary of the River Witham and an important part of Sleaford's natural and historic environment. Historically, it provided a reliable source of water and supported activities such as milling and navigation. In 1872, it was described as a "never-ending source of fresh water". Today, however, the river can experience very low flows, particularly during drier periods.

Throughout Sleaford, there are a number of structures, including sluices, gates and weirs, that help manage water levels for both aesthetic and environmental reasons.

While these structures have played an important role over many years, they can affect the river's natural processes. They can make it harder for fish and eels to move through the watercourse, and contribute to flood risk during periods of high water.

When water levels and flows are high we need to adjust these structures to allow water to flow through and reduce flood risk. The River Slea can also experience low flows because it is strongly influenced by groundwater, some of which is taken for drinking water. This mean the river bed can be dry in some months.

We are reviewing these ageing structures, many of which are becoming more difficult and costly to maintain. Through this project, we are developing options for four key locations along the River Slea. 

Our aim is to improve the way the river works, support wildlife, and create a more resilient River Slea that is better able to cope with both flooding and drought in the future.

We manage four key structures on the River Slea: 

• Cranwell Line Sluice 
• Carre Street Tilting Gate
• Swimming Bath Sluice
• Cogglesford Mill Tilting Gate. 

These structures help control water levels, reduce flood risk and support wildlife and recreation along the river.

As these structures get older, they require more maintenance to keep them working effectively. This project is looking at long-term solutions that will continue to provide these benefits while reducing the amount of maintenance needed in the future.

We are considering a range of improvements to the four structures, including repair, refurbishment and replacement. Where possible, we will look to retain and reuse existing structures and materials.

Cranwell Line Sluice

• We are proposing to replace the existing mechanical sluice gates with more passive structures that will help manage water levels.
• We will retain parts of the existing structure where practical and explore opportunities to improve fish and eel passage.

Swimming Bath Sluice

• We are proposing to replace the existing operating equipment with a simpler structure that will continue to manage water levels effectively while reducing the need for manual operation.
• We also plan to replace the footbridge with a new pedestrian footbridge and improve access for eels.

Cogglesford Mill Tilting Gate

• We are exploring options to refurbish or adapt the existing structure while continuing to manage water levels.
• We will also review opportunities to improve fish and eel passage.

Carre Street Tilting Gate

• We are exploring options to replace the existing structure with a solution that helps manage flood risk, maintains water levels during drier periods, and improves access for fish and eels.
• Since our original proposals were developed, plans for the nearby Savoy Cinema development have changed what can be delivered at this location. We are therefore investigating a revised preferred option and are working closely with North Kesteven District Council to make sure it aligns with wider plans for the area.

As the project progresses, we will continue to refine the designs through the Full Business Case and detailed design stages.

The project team have worked together to develop six key objectives. 

1. Managing flood risk

We want to develop practical, sustainable and long-lasting solutions that help manage flood risk now and in the future. The proposed measures will be designed to work effectively, be resilient to climate change and comply with relevant legal requirements.

2. Improving understanding and awareness

We want to help communities, stakeholders and decision-makers better understand flood risk, water level management and the environmental challenges facing the River Slea and surrounding watercourses.

3. Enhancing the environment

We want to improve the natural environment by supporting wildlife, improving river habitats and working with natural processes wherever possible. We will also look for opportunities to deliver wider environmental benefits as part of the project.

4. Engaging communities

We want to work with local communities, landowners and other stakeholders to build understanding of the project and ensure people have opportunities to share their views as plans develop.

5. Working with others

We want to work closely with local authorities, organisations and other stakeholders to identify opportunities that deliver wider benefits for both the community and the environment.

6. Minimising construction impacts

If the project moves forward, we will work closely with the people of Sleaford during construction and do our best to minimise disruption wherever possible.

We are working with our contractors and Consultants to develop practical, sustainable and cost-effective solutions that help manage flood risk along the River Slea.

Engaging with local people is an important part of the project. We are committed to keeping communities informed and providing opportunities for people to share their views as plans develop. Feedback will help us understand local priorities and shape the project as it progresses.