Tickhill Dam Sluice Gate Replacement

The Brief

Historically, the sluice gate at Tickhill Dam had experienced some issues with reliability, and due to the type of equipment used, had the potential to trap debris on closing - this can not only cause excessive leakage; but previous attempts to close the gate against obstruction had caused damage due to over-torque, leaving the gate inoperable.

Aquatic Control Engineering Ltd (ACE) has over 25 years’ experience in the water industry, primarily working in flood alleviation and land drainage sectors, and reviewed the design of the current structure, identifying the following:

- The vertical door style penstock is not ideally suited for level control, as although it can be triggered automatically, it allows a fast flow of water through a small orifice, pulling debris through with it. Larger debris can then get stuck, and when called to close, the gate stops against the debris to prevent overload. This can cause loss of water and/or downstream flooding and historically at this site, manual winding has then overloaded the equipment in an attempt to close it fully.

- Ideally, this type of penstock should be greased on its spindle, but due to the penstock’s location, this is not practical or safe for the user, and therefore not likely to have been done.

- The drive for the penstock is on an overhead frame, accessed from a narrow bridge. The user needs to climb step irons to access this bridge, which could become unsafe in wet/icy weather.

The Solution

The AQUIKO ATW-PE tilting weir is a different style of sluice, which tilts from the base and allows water to flow over the crest of its weir plate. This addresses the issues above as follows:

- The gate does not allow water through an orifice - any debris carried with the water flows over the structure and is not likely to become trapped. Even if debris does build up over time, it can be cleared at the surface and does not block the drive system, making the weir much more reliable in this application.

- This type of sluice does not require any greasing or maintenance other than clearing floating debris - it has sealed for life gearboxes and does not require any other lubrication.

- The drive is accessible at floor level, next to the existing incoming power supply. This is much safer for the operator and may even allow the removal of the existing bridge over time if desired.

The Result

The tilting weir provided much more flexibility in the control of the water level - it has a much less “aggressive” control philosophy, using only small movements (perhaps more frequently) to maintain the water level as the water cascades over the gate.

The proposed structure was designed to strike a balance between practical, safe and secure operation, and the cosmetic appearance of the surroundings - the actuator that drives the weir was installed at ground level but has secure covers that reduce the risk of tampering, but still allow the operator to use the weir quickly and easily.