Water conservancy aqueduct joint water stop device

The invention discloses a water conservancy aqueduct joint waterstop device which comprises a pair of waterstop plates and at least one drainage pipe, the pair of waterstop plates are arranged on the upstream and the downstream of an aqueduct joint respectively, one end of the drainage pipe stretches into the upstream of one waterstop plate, and the other end of the drainage pipe stretches into the downstream of the other waterstop plate. The upstream water level of one water stop plate is higher than the downstream water level of the other water stop plate, and the two ends of the drainage pipe are both located below the water surface. The water conservancy aqueduct joint waterstop device has the beneficial effects that the upstream and downstream of the aqueduct joint are each provided with one waterstop plate, the aqueduct is partitioned through the two waterstop plates, then the aqueduct continues to normally convey water by means of the drainage pipe according to the siphon principle, in this way, the aq