10910 HOLLY DR 2025-07-28 - Laserfiche WebLink

Goldfinch Brothers Drainage Study 1 August 27,2008 6. UPSTREAM— DOWNSTREAM ANALYSIS DOWNSTREAM CONDITIONS IThe original downstream analysis for the Goldfinch property was completed in 1994 and was approved by Snohomish County. The report mapped the then open Ichannel flow down the Holly Drive roadside ditch for about 300-feet to a culvert that turned the eastbound flow south across Holly to existing wetlands. Since that time the City of Everett has annexed the area and has constructed storm and Ifrontage improvements down Holly Drive. The crossing remains at the historic location. The downstream wetlands have not changed since the 1994 report. Channelized flow still meanders overland to the south through a shallow channel Isupported by shallow wetlands. Photobases 10 and 11 document downstream channel conditions below the wetland area just south of Holly at Hollowdale I Drive. Clearly, the channel has been excavated and straightened by man over recent history. I The City as-built on the following page provided a good plan view perspective of the downstream drainage corridor. The seasonal stream is considered headwaters to Swamp Creek which flows from the northwest to the southeast from the pond IIeast of Home Depot toward Lynnwood east of Highway 99S. Given the restrictions placed in developed flows and the storage volume provided I in the vault the Site discharges are not expected to significantly or even noticeably impact the down stream channel conditions. 1 I I I I 1 I 1 10