Replacing Stop-Logs With Fixed Multistage Polynomial Weirs
(Kashi & Baddour 2018)
Stop-logs are wooden beams, stacked on top of each other, spanning between grooved piers of a spillway. They are added and removed by hand, or with a hoist, to maintain desirable water levels and discharges throughout the year. Stop-log operations are common at the outlet of small lakes and reservoirs. They are expensive to maintain and operate in remote locations. In a recent study, Kashi and Baddour (2018) found it is possible to replace stop-logs by multistage polynomial weirs. A case study was conducted at Halfway Lake Dam located at the outlet of Halfway Lake within the Mada-waska River watershed in Ontario, Canada. The study showed the effectiveness of a multistage polynomial weir system in reservoir water level management. Polynomial weir systems are inexpensive to implement and do not require maintenance.
Stop-logs are wooden beams, stacked on top of each other, spanning between grooved piers of a spillway. They are added and removed by hand, or with a hoist, to maintain desirable water levels and discharges throughout the year. Stop-log operations are common at the outlet of small lakes and reservoirs. They are expensive to maintain and operate in remote locations. In a recent study, Kashi and Baddour (2018) found it is possible to replace stop-logs by multistage polynomial weirs. A case study was conducted at Halfway Lake Dam located at the outlet of Halfway Lake within the Mada-waska River watershed in Ontario, Canada. The study showed the effectiveness of a multistage polynomial weir system in reservoir water level management. Polynomial weir systems are inexpensive to implement and do not require maintenance.
Below is the three-stage weir system proposed for the Halfway Lake Dam. It was designed to produce within +_0.15 m the existing water elevations in the lake upstream. The multistage polynomial weir system performed better that broad-crested and ogee weir solutions, when simulations of water levels were carried out for the average year (2006).