825 N BROADWAY 2017-01-13 - Laserfiche WebLink

Stormwater Pollution Prevention Plan 2.0 Site Description 2.1 Existing Conditions Building Site The building site includes a paved parking lot with landscape curb islands, a sidewalk along North Broadway, and landscape between the sidewalk and the parking lot. The site gradually slopes north to south, with approximately 5 feet of relief across the site. Stormwater runoff from the site generally drains from south to north. Runoff is collected by catch basins and conveyed by storm drain pipe to the combined sewer line to the northeast of the site. Big J's Site Big J's site is a vacant lot with areas of gravel, exposed soil, and non-native and unmaintained vegetation. The site slopes down to the southeast with approximately 6 feet of relief across the site. Runoff is blocked by a short retaining wall on the southeast edge of the site and the current drainage outfall location is unknown at this time. Index Site The Index site is a cleared area from the Index Hall buildings that were recently demolished. The site consists of exposed soil with some grass from stabilization efforts after demolition and a concrete sidewalk bisects the site. The site gradually slopes to the south and east with less than 1 foot of relief across the site. Steeper slopes on the eastern edge of the site will not be impacted by construction. Stormwater sheet flows to the existing catch basins located in the parking lot to the south. Surficial soils genera]]y consist of approximately 1 foot of inedium dense fill consisting of sandy gravel overlying very dense glacial till composed of mostly gravelly sand per the geotechnical report prepared by Hart Crowser on March 4, 2015. Groundwater was not encountered during subsurface investigation, but perched groundwater may existing atop the very dense glacial till. There are no critical areas on site such as high erosion risk areas, wetlands, streams, or steep slopes (potential landslide area). 2.2 Proposed Construction Activities The proposed development wrll construct a four-story academic building and basement, sidewalk along the project frontage, new curb alignment at the intersection of North Broadway and Tower Street, utility and storm drainage infrastructure, landscape and paving around the building, and adjacent parking.