Brief
Ancholme rowing club is based in an unusual environment. Part of the river they use for their sculling practice is an older, pre-diversion section, now used as a water holding area for the nearby steelworks. This means that the level is high in summer and low in winter, the opposite to most lakes and rivers in the UK. The club had an existing concrete landing stage which, due to their unique situation, was underwater during the busiest times of the year. They approached us in 2022 to come up with a more appropriate replacement.
Solution
The ideal option would have been a pontoon, which would respond to the changing water levels automatically, but there wasn’t sufficient space between the river bank and the clubhouse to allow for the access ramp, particularly with the possibility of a rare winter flood. Instead, for stability and ease of access, we provided them with a multi-level jetty with a removable section, so that the ideal freeboard can be given at any time of year. Ancholme has a range of boats from singles to 8-seaters, and the 8s need a 12m landing stage to launch from. We installed a 28m long aluminium jetty along the riverbank, 1.8m wide to allow for the oar outriggers. Made of non-slip GRP grid surface, with a composite board along the front to protect the gunwales of the boats, this section was expected to flood in the summer. Over the top of this was a removable second level to make the regular deep water of summer much more easily accessible for the rowers, especially during their regatta events, the club’s busiest times.
Challenges
The engineering in this job was our main challenge, and we were proud of the four 3m long removable sections that we produced. These were designed to come apart easily, allowing club members to raise or lower the jetty level in just half a day, and store the parts in the limited space of their clubhouse. We also decided to include a low step, making the access down to the lower winter section easier for the rowers, so that they would have two steps of just 200mm rather than a big drop of 400mm while also carrying a boat!
The jetty had to be put in during the low water of winter months, and we had to work around rainy periods. One of the conditions of gaining permission from the Environment Agency was to install it before the breeding season of a number of birds in early spring. This combination of factors meant that timing the installation was one of the main challenges of this project, and we were pleased to get it done with the minimum impact on the wildlife of the area.
