This $15 million dollar project along US-95 in Sandpoint, Idaho, consisted of new 4 lane road realignment, drainage improvements, MSE walls, and pathway construction. The roadway reconstruction consisted of roadway excavation, MSE walls, rock cap placement and included texas turns and the installation of new traffic signals. Deep excavations for the MSE walls over 35 feet were required for slope stability. Construction methods include rock buttresses, chimney drains, pipe under drains, and wick drain installation. In addition, the close proximity to Sand Creek and heavy precipitation were challenges in maintaining compliance with environmental regulations. The project team implemented two 600 GPM Chitosan Enhanced Sand Filtration System (CESF) to treat stormwater runoff.