1. The property owner is responsible for the drainage design and performance of their private drainage facilities;

2. The drainage designer used by the property owner shall be a civil engineer licensed in the state of Washington, provided this requirement does not apply to single-family development or redevelopment that does not require a utility developer extension agreement per BCC 24.06.060(C);

3. Subject to approval by the utility, the property owner may contribute an equitable cost share, as determined by the director, to runoff-control or runoff-treatment facilities that serve multiple sites in lieu of providing such facility(s) on site; and

4. The utility may impose, on any development or redevelopment, requirements that differ from the requirements of this section based on adopted basin plans or other studies adopted by the city council; provided, that such alternative requirements provide an equal or greater level of protection than the requirements of this section.

1. All development and redevelopment shall provide for the control of stormwater runoff so as to minimize impact to downstream properties;

2. The property owner shall maintain natural drainage patterns and discharge drainage in a manner and location that existed prior to undertaking land/runoff altering activities, to the maximum extent practicable, unless the utility determines alterations would be beneficial and would not cause adverse impacts. The utility may require the property owner to complete an off-site capacity analysis per subsection D of this section;

3. Drainage that originates within a building or structure shall be discharged to the sanitary sewer;

4. For conveyance to a public or private surface water system, the property owner shall:

5. Drainage pipe setbacks shall originate from other utilities, structures, and buildings, and structures and buildings shall be set back from existing pipes, as required by the engineering standards; and

6. Regardless of whether the development or redevelopment requires city approval or review, the city is not liable for any impact, should it occur to downstream properties from runoff or for any impact to adjacent or downstream properties from natural drainage patterns and discharge.

1. Protection of open channel conveyances that are located within a stream and associated critical area buffer as defined and designated in Part 20.25H LUC;

2. Where stream bridging is allowed by the land use code, design the bridge to ensure hydraulic capacity pursuant to the engineering standards and to protect water quality as specified in the engineering standards;

3. Where relocation or piping of a stream (as defined and designated in Part 20.25H LUC) is allowed, provide hydraulic capacity pursuant to the engineering standards and provide the same or better water quality protection; and

4. When development or redevelopment is contributing to an existing water quality or capacity problem within an on-site stream or an adjacent-property stream, which could be improved through on-site planting of native vegetation, adding energy dissipation at outfalls, extending roof and footing drains to protect geologic hazard areas, or removing yard debris, obstructions, and rubbish from stream banks, such measures shall be required.