Site work for a civil project in Holden, Massachusetts. Completed plans call for site work for a water / sewer project.

Q And A Open: 20/01/2021 23:30:00 Q And A Close: 10/02/2021 10:30:00 Quabbin Aqueduct Shaft 2 Repairs. Description of Existing Facilities: 1. The Quabbin Aqueduct carries water from the Quabbin Reservoir to the Wachusett Reservoir as part of the MWRA's raw water supply system. Shaft 2 provides pressure relief to the Quabbin Aqueduct by allowing overflows and venting of air into and out of the aqueduct. Shaft 2 overflows occur when high-volume diversions from the Ware River to the Quabbin Reservoir overtax the capacity of the Quabbin Aqueduct and the Oakdale Power Station at Shaft 1. 2. Shaft 2 is constructed of reinforced concrete and has highly cracked shotcrete facing. The above-grade portion of the concrete shaft extends up approximately 18 feet above the surrounding riprap-covered ground surface. The exterior shaft diameter is approximately 22 feet and the interior diameter is 14 feet. On top of the shaft are four openings with hinged steel hatches, four 180-degree-elbowed cast-iron vent pipes, and a steel post-and-picket fence around the edge. 3. The facility was originally constructed around 1927 with the construction of the Quabbin Aqueduct. Modifications to the shaft were made in 1940 and 1957, which lowered the grade around the shaft and increased the diameter of the shaft to its current outside diameter of approximately 22 feet. 4. The invert of the shaft is approximately elevation 250 feet Boston City Base (BCB). The average flow through the aqueduct is approximately 310 MGD at a hydraulic gradeline of approximately elevation 490 feet BCB. Furnish all labor, materials, equipment, and incidentals necessary to complete the Shaft 2 Repairs. The Work includes the following major items of work as indicated and specified: 1. Removal and stockpiling on-site of screened gravel and rip rap ground surface above the concrete slab for reinstallation. 2. Removal and disposal of the 10-inch thick by 10-foot wide concrete apron around the shaft. 3. Removal and stockpiling on-site of the rip rap and gravel under the concrete slab to expose the entire overlay. 4. Removal and disposal of deteriorated shotcrete and reinforced concrete surfaces.