Manhole insert and tether apparatus and method
 A watertight manhole insert and tether apparatus designed to prevent rainwater from entering sanitary sewer or other systems through a manhole closed by a manhole cover. The manhole insert is located beneath the manhole cover and is connected directly to the manhole by a tether apparatus mounted in the manhole, to plug the manhole, prevent theft of the manhole insert and deny access to the manhole. The manhole insert is characterized by a pan-shaped insert body having a curved, flat or ribbed insert bottom and one or more pressure-relief valves, one or more lift straps and an upward-standing, sloping or perpendicular side wall fitted with an outwardly-extending top rim for engaging a shoulder shaped in the manhole to support the manhole insert in the manhole. One end of a flexible stainless steel tether is connected to the manhole insert and the opposite end extends through a pair of tether mount loops fixed to the manhole wall and then through a grommet in the insert bottom and subsequently through a locking device. According to the method of this invention when the manhole insert is placed in the manhole, the tether is tightened in the tether mount loops as it is pulled upwardly through the grommet and the locking device is slipped along the tether above the grommet and locked at the insert body to seat the manhole insert on the manhole shoulder and prevent both theft of the manhole insert and access to the manhole. 
Southwestern Packing & Seals Inc.
E Y Y Y
E02D Y10T Y10T Y10T
inventional additional additional additional
Timothy B. Michael W. David L. Michael D.
Ely Humke Neathery Humke