Article III. - Drainage Permits.

Sec. 11-9.Exemptions from drainage permit requirements.

Sec. 11-8. - Drainage permit requirements.

(a) Permit Required. A drainage permit shall be required prior to commencing any drainage improvement or related work, including preparatory site clearing and soil disturbance, except where exempted from permit requirements by Section 11-9. A separate drainage permit shall be required for each site.

(b) Drainage Improvement Designation and {erformance. Drainage improvement shall be designated in compliance with the requirements in Table 11-2, and shall be performed as follows:

(1) Regular Drainage Improvement. Regular drainage improvement shall be performed in compliance with approved plans and specifications prepared by the property owner or a licensed professional acting within the scope of their license.

(2) Engineered Drainage Improvement. Engineered drainage improvement shall be performed in compliance with approved plans and specifications prepared by a civil engineer.

Table 11-2—Drainage Improvement Designation

[TABLE BELOW]

Parameter	Threshold¹
	Regular Drainage Improvement	Engineered Drainage Improvement
Cross-sectional area of drainage improvement	Does not exceed 2 square feet	Exceeds 2 square feet

1. Examples:

Circular—Diameter is less than or equal to nineteen (19) inches or 1.6 feet, effectively eighteen (18) inches or 1.5 feet.
Vee-ditch—Depth of one (1) foot and top width equal to four (4) feet (assumes 2:1 side slopes).

(Ord. No. 5891, § 7, 12-9-2008.)

Sec. 11-9. - Exemptions from drainage permit requirements.

The following drainage improvement activities are exempt from the provisions of Section 11-8 and may be conducted without obtaining a drainage permit; provided that exempt drainage improvement shall still be subject to the standards in this chapter.

(a) Drainage Improvement Subject to Valid Grading, Building, Septic, Vineyard and Orchard Site Development, or Encroachment Permit. Drainage improvement for grading, buildings or structures, septic systems, vineyard or orchard site development, or within a public right-of-way, where authorized by a valid grading, building, septic, vineyard and orchard site development, or encroachment permit.

(b) Maintenance, Repair, or Replacement of Existing Private Drainage Improvements. Maintenance, repair, or replacement of existing, lawfully constructed private drainage improvements, where the location and design capacity are not changed.

(c)   Minor Pipe and Vee-Ditch Swale Systems. Construction or installation of pipe and vee-ditch swale systems that meet all of
            the following criteria.
            (1)   The drainage area is less than one-half acre for a smooth-walled pipe and/or vee-ditch swale system, or less than one-quarter
               acre for a corrugated pipe system.
            
(2)   The pipe or vee-ditch swale system is not located in the flood-prone urban area.
(3)   The pipe system is a single run, with minimum diameter of eight (8) inches and installed slopes between two percent (2%)and
               four percent (4%), or the vee-ditch swale system is made of earth, grass, or rock, with side slopes no steeper than two (2)
               units horizontal to one (1)  unit vertical (fifty percent (50%)), maximum depth of nine (9) inches, and installed slopes between
               two percent (2%) and four percent (4%).
            
(d)   Public Projects. Drainage improvement for public projects on public property undertaken by or on behalf of the county or a
               local agency governed by the board of supervisors.
            
(e)   Public Trails. Drainage improvement for public trails, where a public agency takes full responsibility for the work. The permit
               authority shall be notified in writing at least thirty days prior to the commencement of the work.
            
(f)   Resource Conservation, Restoration, or Enhancement Projects. Drainage improvement for soil, water, wildlife, or other resource
               conservation, restoration, or enhancement projects, where a public agency assumes full responsibility for the work. The permit
               authority shall be notified in writing at least thirty (30) days prior to the commencement of the work.
            
(g)   Seasonal Agricultural Drainage Swales. Construction or installation of seasonal agricultural drainage swales that meet all
               of the following criteria.
               (1)   The drainage swale is constructed on contour to the maximum extent practicable.
(2)   The flowline slope of the drainage swale does not exceed four percent (4%).
(3)   The drainage swale does not exceed one hundred fifty (150) feet in length.
(4)   The outlet for the drainage swale is protected to prevent soil loss.

(Ord. No. 5891, § 7, 12-9-2008.)