§ 16.40.030.10. Design standards for detention ponds, retention ponds and drainage ditches.

A.

The purpose of this subsection is to establish minimum standards for the location, retaining walls and fencing of detention or retention ponds or drainage ditches. The design and appearance of detention or retention ponds or drainage ditches can take many different forms, ranging from engineered areas, typically found in commercial districts, to more naturalistic forms that are incorporated into the landscaped setting of neighborhood districts.

B.

Stormwater management facilities such as detention or retention ponds or drainage ditches shall conform to the following standards:

1.

Location . Detention or retention ponds or drainage ditches located within a NSM, NPUD, DC, CCT, CCS, CRT or CRS zoning district shall be located behind the principal building to the rear of the property or buried underground:

a.

Where the topographical conditions or hydrology of a particular site prevents use of an underground vault and design constraints require the use of an alternative surface location, information shall be provided to the POD identifying the special conditions and circumstances that prevent compliance. A waiver to this locational requirement may be approved based on a determination by the POD that the waiver is supported by the technical data. The POD's final determination may be appealed to the Development Review Committee.

2.

Retaining walls . Retaining walls shall comply with the following:

a.

Retaining walls for a surface stormwater management system are prohibited within the DC, CCT, CCS, CRT or CRS zoning districts, however, where the hydrology or specific conditions of a site requires use of a retaining wall, information shall be provided to the POD identifying the special conditions and circumstances that prevent compliance. A waiver to this requirement may be approved based on a determination by the POD, that the waiver is supported by the technical data. The POD's final determination may be appealed to the Development Review Commission.

b.

All retaining walls shall be constructed of decorative masonry block, including but not limited to, split-face CMU's.

3.

Fencing . Any fence or wall (not including retaining walls) shall comply with the requirements of the fences, walls and hedges section and the following:

a.

For detention or retention ponds or drainage ditches which are visible from a major street, or which are located within a DC, CCT, CCS, CRT or CRS zoning district, fences and walls shall be decorative or vinyl coated chain link (including stands, poles and rails);

b.

All fencing shall be located behind the landscaping required by the landscaping section;

c.

A gate shall be provided to allow access for general maintenance purposes.

(Code 1992, § 16.40.030.10; Ord. No. 1029-G, § 29, 9-8-2011)