Hydraulic and earth engineering – Fluid control – treatment – or containment – Flow control
Patent
1985-05-01
1987-04-14
Husar, Cornelius J.
Hydraulic and earth engineering
Fluid control, treatment, or containment
Flow control
405 87, 405100, 415148, E02B 808
Patent
active
046574344
DESCRIPTION:
BRIEF SUMMARY
This invention relates to river control structures. The term "river" is used herein to include any running stream of water and thus extends, for example, to canals and other watercourses, whether natural or artificial.
It is frequently necessary to provide means for controlling the flow of water, for example to provide water storage. Other uses for river control structures include river flow gauging stations and weirs to retain water for irrigation or extraction for public water supply.
One particular type of structure which has been used for river control is known as an "upstream tilting gate." This type of structure includes a longitudinally extending platform, the downstream end of which is supported with freedom to rotate about an axis extending across the river, and the upstream end of which is supported by control means adapted to raise and lower that end.
Whenever a new control structure is provided on a migratory fish river, it is necessary to provide suitable conditions for migrating fish to surmount the structure en route to their spawning beds in the upper reaches of the river. In the past this has been accomplished by separate fish passes, usually flanking the control structure.
The present invention seeks to provide an economically and biologically more satisfactory solution to the problem of enabling fish to surmount a river control structure.
Accordingly in one aspect of the present invention there is provided a river control structure comprising a chamber having side walls between which a longitudinally extending platform is adapted for orientation across a flowing stream and arranged to pass water across an upper surface of the platform in a flow direction, said platform having an upstream and a downstream end, the downstream end of said platform having mounting means allowing the platform to rotate about a horizontal axis extending transverse to the stream, the upstream end of said platform being supported by control means adapted to raise and lower the upstream end of said platform from a minimum to a maximum height, baffled channel means provided for the upper surface of said platform extending in the flow direction, said baffled channel means having baffles disposed therein and arranged such that, when the upstream end of said platform is raised to its maximum height the permitted water flow through said baffled channel means will allow fish to swim upstream through the baffled channel means.
A considerable study of the jumping and swimming capabilities of fish, and in particular of sea trout and salmonids, has shown that a baffled channel, designed to restrict water flow to 0.85 meters per second, can be safely negotiated by migrating fish. In the case of sea trout, the design provides a factor of safety greater than 2.
It is preferable therefore that the baffles in the channel are so arranged that, even when said upstream end of the said platform is raised to its maximum height, the water flow down said channel means will not exceed 0.85 meters per second.
The channel should be designed in such a way that it will contain the turbulent flow caused by the baffles. For this purpose the sides of the channel should extend above the normal water level. These extended side walls will also serve to confine disorientated fish within the channel. Preferably the channel is located substantially on the longitudinal centre line of the platform and normally it will be convenient for the sides of the channel to extend above the upper surface of the platform to approximately the same extent as they descend below it.
The lower end of the channel is preferably designed in such a way as to produce turbulence, which will attract the migrating fish. In addition, or alternatively, an additional downstream wall may be provided with a notch in the centre of the top of the wall to guide the fish towards the lower end of the channel.
The baffles may be arranged in any way which will restrict the flow to 0.85 meters per second at the maximum inclination required. In particular it has been found that an arrange
REFERENCES:
patent: 1036613 (1912-08-01), Hall
patent: 2317975 (1943-05-01), Boath et al.
patent: 3336756 (1967-08-01), Isenberg et al.
Augspurger Lynn L.
Hall Kristina I.
Husar Cornelius J.
LandOfFree
River control structures does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with River control structures, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and River control structures will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1781754