Granite Creek Rock Quarry Reconfigured Lease Lot 4 Stormwater Outfall, Sitka, Alaska

Granite Creek Rock Quarry Reconfigured Lease Lot 4 is a stormwater outfall located at the Granite Creek Industrial Site on Granite Creek Road in Sitka, Alaska. This facility manages stormwater runoff from a quarry and industrial lease lot, contributing to local flood control and water quality management in the Sitka City and Borough area. As a stormwater outfall in the United States, this facility operates under the Clean Water Act and is subject to EPA NPDES MS4 permit requirements. For industrial sites like quarries, stormwater discharges are typically regulated under Multi-Sector General Permits (MSGP) that mandate best management practices (BMPs) for erosion control, sediment management, and pollutant prevention. The facility's location in a coastal Alaskan environment with significant rainfall and snowmelt necessitates robust stormwater infrastructure. The outfall discharges into Granite Creek, which flows into the Pacific Ocean near Sitka. Proper stormwater management is critical to protect local water quality, aquatic habitats, and downstream ecosystems. The facility's operational status indicates ongoing compliance with regulatory standards to minimize environmental impact from industrial runoff.

Sitka, Alaska, experiences a temperate maritime climate with high annual precipitation (over 200 cm), leading to significant stormwater runoff. The Granite Creek watershed drains into Sitka Sound, a productive marine ecosystem supporting salmon, herring, and other wildlife. Industrial activities at the quarry pose risks of sediment, heavy metals, and hydrocarbon pollution. Effective stormwater management is essential to prevent degradation of these sensitive coastal waters and maintain compliance with the Clean Water Act.