Automatic trip gate

An automatic trip gate for installation in a gate support structure for releasing overflow water from an impoundment of water through the gate support structure, the automatic trip gate comprising:

• a hinged support arm assembly including a foot, a first end of the foot adapted to be pivotably attached to the gate support structure at an axis of rotation;
• a plate attached to and extending from a second end of the foot of the hinged support arm assembly, the plate attached to the second end of the foot upstream of the axis of rotation, a weight of the plate combined with a length of the attached foot extending between the plate and the axis of rotation providing a moment to resist an opposite hydraulic force of the impounded water;
• a trough attached to the plate, the trough positioned downstream from the plate and downstream from the axis of rotation of the hinged support arm assembly, the trough adapted to catch and retain overflow water flowing over the plate, the trough including means for regulating a level of overflow water retained in the trough;
• and
• the foot of the hinged support arm assembly and the attached plate and trough further adapted to pivot at the axis of rotation of the hinged support arm assembly from a substantially vertical orientation wherein the impounded body of water is maintained upstream of the plate, to a tipped position, caused when a weight of the trough and the overflow water retained by the trough reach a tripping level creating an overturning moment, wherein the foot of the hinged support arm assembly and the attached plate and trough tip, and the impounded body of water is released over the tipped plate.

An automatic trip gate system for installation in a bank of an impounded body of water for controlling a release of an overflow of water from the impounded body of water, the automatic trip gate system comprising:

• a spillway including a gate support structure installed in the bank of the impounded body of water;
• an automatic trip gate installed in the gate support structure, the automatic trip gate including a hinged support arm assembly including a foot, a first end of the foot pivotably attached to the gate support structure at an axis of rotation, a plate attached to and extending from a second end of the foot of the hinged support arm assembly, a weight of the plate combined with a length of the attached foot extending between the plate and the axis of rotation providing a moment to resist an opposite hydraulic force of the impounded water, a trough attached to the plate, the trough positioned downstream from the plate and downstream from the axis of rotation of the hinged support arm assembly, the trough adapted to catch and retain overflow water flowing over the plate from the impounded body of water, and the foot of the hinged support arm assembly and the attached plate and trough further adapted to pivot at the axis of rotation of the hinged support arm assembly from a substantially vertical orientation wherein the impounded body of water is maintained behind the plate, to a tipped position, caused when a weight of the trough and the overflow water retained by the trough reach a tripping level creating an overturning moment, wherein the foot of the hinged support arm assembly and the attached plate and trough tip, and the impounded body of water is released over the tipped plate.