All drainage studies and drainage plans as herein required shall be based upon estimates of peak and total discharges.
A. Drainage Study:
1. The drainage study shall identify the essential elements, alignments, and functions of a drainage system.
2. The drainage study shall show the following site conditions:
a. Details of existing site drainage and/or irrigation features including, but not limited to, ditches, watercourses, and drainage structures;
b. The permeability and types of soils and geologic materials;
c. The size of the drainage basin upstream;
d. The topography, slope, and geometry of the site;
e. The proximity of surface water within one hundred feet (100');
f. The proximity of potable water supply wells within one hundred feet (100');
g. The proposed use and potential contaminants; and
h. The past use and possible soil and/or ground water contamination.
3. Other supplemental data as may be required by the county engineer.
4. The drainage study requirement is also met if the study information required is shown on the drainage plan.
B. Drainage Plan:
1. When a condition of approval requires approval of a drainage plan by the county engineer, the applicant shall submit a drainage plan to the director for design approval by the county prior to issuance of a zoning certificate.
2. The drainage plan shall be drawn to scale and shall include, but not be limited to, the following:
a. All proposed grading to be done on the property;
b. Essential elements, alignments, and functions of the proposed drainage system including, but not limited to, sewers, storm drains, catch basins, pumps, and seepage beds;
c. The drainage plan shall indicate by flow arrows, contours, spot elevations, or some other acceptable manner, where storm water will be routed for the property. It must show the location and size of any flows onto the site from outside the property boundaries as well as any discharges leaving the site;
d. The proposed use and potential contaminants;
e. When drainage courses and irrigation facilities exist on site, the owner and/or applicant shall provide documentary evidence of consent to reroutings by all interested landowners and drainage and irrigation entities affected and having rights to, and in, such facilities; and
f. Other supplemental data as may be required by the county engineer.
(Ord. 389, 6-14-2000; amd. Ord. 426, 9-26-2001; amd. Ord. 902, 10-2- 2019)