A.
Stormwater controls for temporary or permanent conditions shall be determined based on the proposed activities, project schedule, and project phasing.
(Ord. 2316 § 1 (part), 2010; Ord. 2356 § 11 (part), 2011)
A.
It shall be unlawful for any individual, firm, or corporation to throw, drain, or otherwise discharge, cause, or allow others under its control to throw, drain, or otherwise discharge into the municipal storm drain system and/or surface and ground waters any materials other than stormwater.
B.
Products of erosion shall be prevented from entering the public drainage system at all times, both during construction on the property and the subsequent operation of the facilities. All trash and debris shall be prohibited from entering the drainage system at any point within the property.
C.
Discharges from commercial or industrial vehicle washing facilities within the sanitary sewer service area shall discharge to the sanitary sewer following pretreatment for removal of large solids, oil, and grease. Washing areas shall be covered, sloped, or curbed to minimize entry of uncontaminated stormwater into the sanitary sewer system. Wash water containing nonbiodegradable detergents, degreasers, or other cleaning compounds shall not be discharged to any surface water or watercourses, either directly or via the storm sewer system.
1.
In areas outside of the sanitary sewer service area, whenever feasible, vehicle wash systems shall be closed systems with recycling of wash water, and with treatment which includes oil/water separation followed by disposal of any sludge or sediment.
D.
Whenever a known discharge of any potentially deleterious material shall occur, the responsible party shall immediately notify the city of the existence of such discharge and the location thereof.
1.
The notification required by this section in Sumner shall be given by telephoning the city's public works department during normal business hours, or the Sumner police department after normal business hours, or other such emergency number as may be designated.
2.
The requirements of this chapter shall not be construed to forbid the responsible party from using all diligence necessary to control such discharge prior to notification, especially if such efforts may result in the control or containment of the discharge or abatement of hazards or adverse impact.
3.
No statement contained in this chapter shall be construed to exempt or release any person from any other notification or reporting procedure required by the state of Washington or any federal agency.
(Ord. 2316 § 1 (part), 2010; Ord. 2356 § 11 (part), 2011)
A.
Stormwater management measures shall be required to satisfy the minimum control requirements. The stormwater management practices to be utilized in developing a stormwater site plan shall be according to the following order of preference:
B.
LID practices that are proposed for the project shall be documented in the stormwater site plan. If LID practices are not technically feasible, as determined by the engineer of record and concurred by the city engineer or his or her designee, the stormwater site plan shall document the technical limitations that preclude the use of LID practices.
C.
The city engineer or his or her designee shall have final approval on the technical design factors that preclude the use of LID practices.
(Ord. 2316 § 1 (part), 2010; Ord. 2356 § 11 (part), 2011)
A.
Stormwater management measures shall be designed and constructed in accordance with the standards and specifications as set forth in the Manual and the Sumner Development Specifications and Standard Details.
B.
Design standards and specifications required by any applicable special district shall be used if such standards and specifications provide greater protection of public health, resources, and property.
C.
Open water quality treatment facilities that rely on retaining a permanent volume of water, such as wet ponds or combined detention and wet ponds, are prohibited from new construction. Open water quality facilities are also prohibited on redevelopment projects that require new or modified water quality treatment for previously constructed impervious surfaces or previously disturbed pervious surfaces.
D.
All water quality treatment facilities required for developments discharging runoff to surface waters shall be selected from the Enhanced Treatment Menu in Chapter 3, Volume V of the manual.
(Ord. 2316 § 1 (part), 2010; Ord. 2356 § 11 (part), 2011; Ord. 2586 § 2 (part), 2016)
Where individual basin plans developed by the city or other agencies specify stormwater design criteria differing from those attached herein, the requirements of the basin plan shall govern; provided, that the basin plan has been approved by Ecology and adopted by local ordinance. Additional requirements regarding the applicability of basin plans can be viewed in the NPDES Phase II permit, Appendix 1, Section 7.
(Ord. 2316 § 1 (part), 2010; Ord. 2356 § 11 (part), 2011)
When it is deemed necessary by the city, as a condition of development for the applicant, to install conveyance lines larger than required to serve adjacent properties, such development may be eligible for reimbursement through a latecomer agreement as stated in SMC § 13.48.335. The storm drainage utility may participate in the cost to construct said oversizing upon council approval.
(Ord. 2316 § 1 (part), 2010; Ord. 2356 § 11 (part), 2011)