Water flow shutoff system

A toilet water flow shutoff apparatus, comprising:

• a vessel configured to be mounted within a toilet tank in a stationary relationship therewith, the vessel having an interior volume and a rim defining an open top, wherein the toilet tank contains an inflow conduit having a fill valve and an outflow opening selectively sealable by a flapper valve;
• a float disposed within the vessel and operatively connected to the fill valve, wherein the fill valve is closed when the float is in a raised position and wherein the fill valve is open when the float is in a descended position, the float being configured to transition into the raised position when a water level within the vessel reaches a predefined height and configured to transition into the descended position when the water level within the vessel falls below the predefined height,
• an actuation lever pivotally disposed within the toilet tank, the actuation lever having a first end and a second end, wherein the first end and the second end are disposed on opposite sides of a fulcrum, wherein the second end of the actuation lever is biased toward the vessel and wherein retracting the second end of the actuation lever away from the vessel causes egress of water from the vessel;
• and
• a first mechanical connector affixed to the first end of the actuation lever and configured to connect to a toilet flush handle, wherein actuation of the toilet flush handle is configured to apply tension to the first mechanical connector causing the actuation lever to pivot about the fulcrum thereby retracting the second end of the actuation lever away from the vessel and causing egress of water from the vessel, such that the water level within the vessel falls below the predefined height, thereby transitioning the float into the descended position and opening the fill valve to refill the toilet tank, and wherein the float is configured to remain in the descended position until the vessel becomes refilled with water to the predefined height.