Peak Control Infrastructure

Capacity-constrained is defined by the Stormwater Code, SMC 22.801.040 as a drainage system that the Director of SPU has determined to have inadequate capacity to carry drainage water. There are three distinct areas that compromise what is currently mapped as capacity-constrained, 1) the entire network comprising the informal drainage system consisting of the intermittent ditch and culvert network as these were never engineered, they are inherently capacity constrained. 2) The infrastructure contained in the Densmore Basin which discharges to a King County storm drain which was not designed with capacity to convey runoff from the increased density from additional development. 3) a portion of the public storm drain system on Capitol Hill upstream from the maintenance hole at the intersection of Pike St & Melrose Ave, there is a hydraulic restriction in this maintenance hole which leads to an extremely elevated hydraulic grade line and associated localized surface flooding. For more information on this Code please see, https://water.epa.gov/polwaste/nps/upload/nps-ordinanceuments-seattle-code.pdf容量受限（Capacity-constrained）由《雨水法规》（Stormwater Code）SMC 22.801.040定义为：经西雅图公共事业局（SPU）主管认定，不具备足够雨水输送能力的排水系统。当前被标注为容量受限的区域分为三类： 1） 包含非正规排水系统的完整管网：该系统由间歇性沟渠与涵洞管网组成，因从未经过工程设计，天生存在容量受限问题。 2） 登斯莫尔流域（Densmore Basin）内的排水设施：该设施最终接入金县（King County）雨水管道，原设计未考虑应对新增开发带来的开发强度提升所产生的径流输送需求。 3） 国会山（Capitol Hill）区域公共雨水管道系统的一段：该段位于派克街（Pike St）与梅尔罗斯大道（Melrose Ave）交叉口检查井的上游，此检查井存在水力限制，导致水力坡度线大幅抬升，进而引发局地地表积水。 如需了解该法规的更多信息，请访问：https://water.epa.gov/polwaste/nps/upload/nps-ordinanceuments-seattle-code.pdf