6522 WETMORE AVE 2025-08-19 - Laserfiche WebLink

SECTION VIII: PERMANENT STORMWATER CONTROL PLAN A. OFF -SITE ANALYSIS A site reconnaissance was performed by Brian Kalab of Insight Engineering on Feb 24, 2020 to verify the downstream flow paths and observe any drainage problems downstream of the site. The sky was partly cloudy and overcast with a temperature of 45 degrees. The site contains 0.39 Acres. The site is currently developed with a home and a gravel driveway from Wetmore Ave. The remainder of the site exists as lawn and native vegetation. The site contains one drainage basin that that slopes slightly to the east. Upstream Analysis Based on the site reconnaissance and the topographic survey of the site, the off -site area entering the site is very minimal. Refer to the Downstream Analysis Map attached in the next page for more details. Downstream Analysis Refer to the Downstream Analysis Maps 1 and 2 attached to the next pages for a visual description of the downstream flow. The site drains to the east and flows into the existing drainage system along Wetmore Ave. The system heads south and combines with the sewer system. The flow continues north through a 12-in Concrete Pipe for about 660-ft and then continues east for 1200 ft along Lexington Ave and then continue flowing northeast along Commercial Ave for about 1020 ft. The flow then turns east along 6 1 " ST SE and continues flowing north through a 12-in PVC pipe up to I mile along Broadway. This is where the downstream analysis was concluded. Mitigated Runoff The runoff from roofs will be connected to the existing drainage system along Wetmore Ave to continue its natural drainage pathway. The runoff from other hard surfaces will be infiltrated via permeable pavement. The flow is minimal and therefore the downstream channel should not experience any flooding or erosion problems in the future. Insight Engineering Co. — Stormwater Site Plan 05/31/2022 -22-