W912dr21b0007 | Third High Reservoir

The Washington Aqueduct provides potable water to approximately one million people in the District of Columbia and Northern Virginia. As part of the water treatment and supply system, the Washington Aqueduct maintains and operates the Dalecarlia and McMillan Water Treatment Plants (WTPs). Potable water from these WTPs is pumped via the third high service to the Third High Reservoir, which has a capacity of 20 million gallons (MG). The Third High Reservoir, also known as Fort Reno Reservoir, is located next to Fort Reno Park in northwest Washington, DC. It is a sub-surface concrete structure measuring approximately 380 feet x 300 feet and 26 feet deep. This reservoir was constructed in mid-1950s. The Washington Aqueduct is in the planning phase for a construction contract for implementing upgrades and improvements to the Third High Reservoir to address operational and sanitary survey issues previously identified. This will result in improved water quality and operation within the distribution system. The work includes architectural, mechanical, electrical and civil improvements to the finished water storage structure that will increase its reliability and improve its function and the replacement of the influent and effluent buildings; the replacement of large valve assemblies; installation of mechanical mixers; sealing of joints and cracks; the re-routing of a sample line and the interception of the reservoir drain line to construct a deep manhole to separate flow from the sewer system by creating an air-gap. The project site is located within the Fort Reno Park, Washington, D.C. The project consists of implement upgrades and improvements to the Third High Reservoir to address operational and sanitary survey issues previously identified. This will result in improved water quality and operation within the distribution system. The work includes the replacement of the influent and effluent buildings; the replacement of large valve assemblies; installation of mechanical mixers; sealing of all interior joints and cracks; the re-routing of a sample line and the interception of the reservoir drain line to construct a deep manhole to separate flow from the sewer system by creating an air-gap. This reservoir is a critical component of the distribution system and so the reservoir outage period is restricted. Hence, an experienced contractor with resources and expertise to handle the following project constraints is needed.

Division 02 -	Existing Conditions, Subsurface Investigation.
Division 31 -	Earthwork, Site Clearing, Grading, Excavation and Fill, Subgrade Preparation, Excavation, Shoring, Tunneling and Mining, Tunnel Excavation.
Division 35 -	Waterway and Marine Construction, Dam Construction and Equipment.