Hill Top Reservoir, also known as Slaithwaite Reservoir, is situated in Slaithwaite, Huddersfield.
It was built 1795 -1799 by renowned canal engineer Benjamin Outram to supply water to the Huddersfield Narrow Canal.
Today, the reservoir is cared for and maintained by us and is a popular spot for walkers and anglers.
To ensure that reservoirs like this are meeting present day standards (as required under the 1975 Reservoirs Act), essential maintenance and upgrade works are required.
Two key elements will be undertaken on this project, to maintain the existing reservoir dam structure and to upgrade the overflow spillway to increase its resilience.
CGI image
Early works
Pre-construction activities began earlier this year to prepare the site safely and efficiently.
Access routes have been created for the safe movement of vehicles, equipment, and materials. Stone used to construct these access routes will later be reused within the embankment.
A crane platform has been installed to safely support lifting operations to the spillway area.
Materials and equipment have been safely delivered and stored on site.
Water control systems have been temporarily adapted, with valves relocated to maintain safe flows to the Huddersfield Narrow Canal and the Clough
There’s been a great deal happening at the reservoir over recent months, much of it behind the scenes. While some of the work may appear highly technical, every step is carefully planned. Our aim is not only to strengthen the reservoir, but to do so in a way that respects its history and its place within the community.
Tunnel and drop shaft - protecting the past
Hidden beneath the reservoir is an important part of its story - the original tunnel and drop shaft. First constructed in 1852, these historic features once played a key role in managing water levels during periods of extreme weather.
As part of the current work, these structures have been carefully strengthened by filling them with concrete and specially designed drainage pipes. This means we can keep their original layout and protect their historic importance, while still allowing water to flow safely through them.
At the same time, this work makes these centuries-old structures strong enough to support the new spillway above. It’s about finding the right balance between protecting the past and preparing for the future.
Rocky gorge - safety first
The rocky gorge below the reservoir is a well-known and striking part of the landscape, but it can be challenging to work in during construction.
To keep everyone safe and protect the new structures, we’ve taken steps to make the area more stable. Loose rocks have been removed and the protective netting is in place to prevent rockfalls, keep the work teams and the new spillway safe while also helping with longterm stability in the gorge.
Caring for the natural surroundings
We know how important natural surroundings are to the community and looking after the environment around the reservoir has been a key priority during this project.
Before the main construction phase began, some of the trees and vegetation around the reservoir were removed. This is a standard procedure and was required to facilitate access. This work was carefully planned with support from our ecologist to reduce environmental impact and avoid disturbing wildlife, especially during nesting seasons.
Following full project completion (which will be several months after the construction phase has completed) we will carry out a replanting scheme to replant as many trees as possible on site.
In your community
We're proud to support local STEM (Science, Technology, Engineering and Maths) initiatives in the community, helping young people to understand the skills and career options involved in looking after our waterways. Through school workshops, challenges and project engagement, we aim to:
Inspire interest in engineering and environmental careers
Show how real-world projects work
Support future skills and opportunities
Have your say
As the project continues, your feedback is really important to us. We want to understand your experience of the project so far, including how effectively we’ve engaged with the community and where we can improve. We’ve created a short survey to give you the opportunity to share your thoughts. Your feedback will help shape how we continue to engage with the Slaithwaite community and ensure the project reflects what matters most to local people. To take part, please visit our online survey
Working with local schools
Building the future at Nields Academy
During Science Week at Nields Academy, classrooms were transformed into mini engineering hubs. Pupils worked together to design and build towers using K’nex, testing their creativity, teamwork and problemsolving skills.
Real-world challenges tackled at Colne Valley High School
At Colne Valley High School, students were challenged to take things a step further by considering the bigger picture behind modern engineering projects.
As well as designing their structures, they explored how decisions are influenced by cost and environmental impact. Balancing these factors encouraged thoughtful discussions and gave students a valuable insight into how real-world projects are planned and delivered.
Crane naming competition
On 5th June, we welcomed the Eco Warriors Committee from Nields Academy to the reservoir for a special visit, organised by JN Bentley and Canal & River Trust. The primary school pupils joined our newly trained volunteer guides for a special visit to learn about the works, how the reservoir supports Huddersfield Narrow Canal and the STEM careers and skills involved. During the visit, the winning name for the project’s giant crane, chosen through a school-wide competition, was officially unveiled. Meet ‘Niel’!
Updates and keeping in Touch
We will share regular project updates on this webpage. We will be keeping local residents and interested parties informed in advance of important updates around project timescales, temporary footpath closures and construction traffic.
You can contact our team with any questions or comments.
Telephone (Freephone): 0808 281 4669 (lines are open weekdays, excluding bank holidays, 9am – 5pm.
Meet our volunteers
Starting from 13 July, a dedicated group of local volunteers are leading site tours along the Slaithwaite Reservoir crest footpath and sharing their knowledge about the works taking place.
Where: Slaithwaite Reservoir crest footpath
When: Second Monday and the fourth Friday of each month
