Test plug

A disposable plug for installation in a cylindrical water line to temporarily block the water line to the passage of water therethrough, said disposable plug comprising a cylindrically shaped tablet having an upstream face, a downstream face, and a diameter substantially equal to the diameter of the water line so that when installed within the water line, water is prevented from passing said disposable plug and a hole configured therein, between said upstream and downstream faces, said cylindrically shaped tablet being characterized as being at least partially dissolvable when contacted with water, an expandable balloon membrane surrounding at least a portion of said cylindrically shaped tablet to selectively prevent water from contacting said cylindrically shaped tablet as long as said expandable balloon membrane is intact over at least said upstream face, an air supply inlet at said hole for supplying pressurized air through said hole to said upstream face of said cylindrically shaped tablet and a supply of pressurized air sufficient to expand said expandable balloon membrane to rupture said expandable balloon membrane to allow water to contact said cylindrically shaped tablet when said water line is not intended to be so blocked.

A method for temporarily blocking the passage of water through a water waste line for creating a pressure head within said waste line, said method comprising installing a disposable plug within said waste line, said disposable plug comprising a disposable plug for installation in a cylindrical water line to temporarily block the water line to the passage of water therethrough, said disposable plug comprising a cylindrically shaped tablet having a diameter substantially equal to the diameter of the water line so that when installed within said water line, water is prevented from passing said disposable plug, said cylindrically shaped tablet being characterized as being at least partially dissolvable when contacted with water;

• a water impermeable membrane surrounding at least a portion of said cylindrically shaped tablet to selectively prevent water from contacting said cylindrically shaped tablet as long as said disposable plug acts to temporarily block said water line;
• and means for disrupting said water impermeable membrane a sufficient amount to allow water to contact said cylindrically shaped tablet when said water line is not intended to be so blocked.