B14 FLOAT VALVE MANHOLE MODIFICATION

Problem Description: Three manholes need their manhole covers modified. The covers of float valves' manholes at B14 are really heavy and need four people to lift each cover. They are also of cast iron and potentially will chip off rust which eventually will end into the potable water tanks. Depth of water manhole WM-01 is not long enough so the handwheel has very little clearance from the top slab to allow ease of valve operation. Limited height clearance makes difficult entrance to the manhole itself. Mission Impact: Difficult for water operators to remove the manholes during PMs and emergencies. Rust is a potential hazard to drinking water. Very difficult for the operator to shut/open the valve during PMs or during emergencies (lack of adequate clearance between handwheel and slab). In case of a valve replacement, it's impossible to remove the big size valves from the existing manhole covers (which are located in the corner of the manhole). Proposed Solution: Replace the existing covers with hinged and locked stainless steel covers. Replace the top slab of manhole and construct a new one with four rectangular covers in a row, at the centerline of the manhole. In this way water operators can remove all four manhole covers and work efficiently when needed.