This design build project in Northern Virginia had nearly 10 miles of retaining walls that elevated the Washington Metro Area Transit Authority (WMATA) silver line track above existing grade. To relieve the hydrostatic water pressure behind these retaining walls, it was vital to have proven wall drainage. The original drainage idea was to use No. 57 aggregate and 8” perforated pipe. Pulling from experience with SITEDRAIN on Virginia DOT road and bridge, the CRC team showed WMATA that SITEDRAIN 180 would have considerably higher flow capacities then the original design. Additionally the SITEDRAIN 180 saved substantial time and money on the installation totally roughly a half million dollars in total cost savings to the Silver Line team.