The original plans approved in 2017 by the Washington Suburban Sanitary Commission (WSSC) for Elizabeth Square included the replacement of the 10-inch sewer line on the west portion of the WMATA and CSX tracks with a 12-inch line that did not go under the tracks. The current proposed Purple Line development design approved by WSSC includes an alternate sewer line routed under the tracks. WSSC now requires HOC, in coordination with Purple Line Plan (PLP), to install an upsize 15-inch sewer line along the alternative route to meet the capacity of both Elizabeth Square and the proposed HOC Headquarters building at Fenwick Lane and Second Avenue. WSSC requires the revised plans to be in effect before the Elizabeth House III and the South County Regional Recreation and Aquatic Center (SCRRAC) building can obtain an occupancy permit.
The current approved contract documents indicate that the new Capital Crescent Trail (located in between Elizabeth House and CSX/Washington Metropolitan Area Transit Authority (WMATA) tracks), including the associated retaining wall, trail and storm systems will be completed by the Maryland Transportation Authority (MTA)/Purple Line. The HOC project will eventually connect into these Capital Crescent Trail storm systems in order to achieve final inspections. However, MTA/Purple Line is not scheduled to install these Capital Crescent Trail storm systems until after the HOC project completion date. As a result, HOC must install a temporary 15-inch storm line to accommodate the Elizabeth House III and South County Regional Recreation and Aquatic Center (SCRRAC) project until MTA/Purple Line is completed.

There is a need to replace the 10-inch sewer line with a 15-inch one because the flows were too low to meet capacity for Elizabeth Square, including the SCRRAC, and HOC office building. The sewer upgrades work must be implemented prior to March 2022 in order to maintain the overall project schedule and prior to Elizabeth House III and SCRRAC receiving a certificate of occupancy. This work was previously to be undertaken by MTA per the Purple Line project. However, the MTA work has been delayed beyond HOC's projected occupancy date.

The total estimated projected costs for installing the upgraded sewer line and temporary storm line is $705,000. Installation of the 15-inch sewer line is estimated at $430,000 and includes hard costs of $230,000, soft costs of $100,000, and a contingency of $100,000. Installation of the 15-inch temporary storm line is estimated at $275,000 which includes hard costs of $100,000, soft costs of $75,000, and a contingency of $100,000.

Department of Finance, Department of Housing and Community Affairs, Department of Permitting Services, Department of General Services, and Maryland Transportation Authority.