Chapter 18.21 SITE ASSESSMENT

Chapter 18.21
SITE ASSESSMENT

Sections:

18.21.010 Site assessment.

18.21.070 General design criteria.

18.21.010 Site assessment.

A. The site assessment requirements of this chapter shall be submitted in addition to all other requirements for development approval of a project including land actions proposed under Chapter 14.15 NMC (Property Grading Regulations) and NMC Title 17 (Site Development).

B. Purpose of the Site Assessment. The purpose of the site assessment is intended to demonstrate that the site design complements the predevelopment hydrologic conditions on the site. This includes documenting soil type and site conditions to determine the feasibility for the use of LID principles and BMPs. The development context shall be established by an initial site assessment consistent with the requirements of this section. The initial inventory and assessment process will provide baseline information necessary to design strategies that preserve natural resources, preserve areas most appropriate to evaporate, transpire, and infiltrate stormwater, and achieve the goal of maintaining predevelopment natural hydrologic conditions on the site.

C. The site assessment shall include, at a minimum, the following information:

1. A survey prepared by a registered land surveyor or registered civil engineer showing existing public and private development, including utility infrastructure, on and adjacent to the site, major and minor hydrologic features, including seeps, springs, closed depression areas, drainage swales, and contours as follows:

a. Up to 10 percent slopes, two-foot contours.

b. Over 10 percent to less than 20 percent slopes, five-foot contours.

c. Twenty percent or greater slopes, 10-foot contours.

d. Spot elevations shall be at 25-foot intervals.

2. A soils report prepared by a licensed geotechnical engineer or licensed engineering geologist. The report shall identify:

a. Underlying soils on the site utilizing soil pits and soil grain analysis to assess infiltration capability on site. The frequency and distribution of soil pits shall be adequate to direct placement of the roads and structures away from soils that can most effectively infiltrate stormwater.

3. Preliminary drainage report consistent with the requirements of NMC Title 13. The report should clearly state the assumed conventional storage volume and LID storage volume in the introduction.

a. Topological features that may act as natural stormwater storage or conveyance and underlying soils that provide opportunities for storage and partial infiltration.

b. Depth to groundwater.

c. Geologic hazard areas and associated buffer requirements as defined in Chapter 18.24 NMC.

4. A survey of existing native vegetation cover by a licensed landscape architect, arborist, or qualified biologist identifying any forest areas on the site, species and condition of groundcover and shrub layer, and tree species and canopy cover.

5. A streams, wetland, and water body survey and classification report by a qualified biologist showing wetland and buffer boundaries consistent with the requirements of Chapter 18.24 NMC, if present.

6. Flood hazard areas on or adjacent to the site, if present.

7. Aquifer and wellhead protection areas on or adjacent to the site, if present.

8. Any known historic, archaeological, and cultural features located on or adjacent to the site, if present.

9. Description of the proposal including:

a. Total area proposed for disturbance;

b. Total area of native vegetation area;

c. Total number of units, or nonresidential building area proposed;

d. Maximum impervious surface proposed;

e. Total area of impervious surfacing.

10. Areas of disturbed soils to be amended.

11. The location and square footage or approximate location and square footage or acreage of all areas to be conveyed, dedicated or reserved as common open spaces, public parks, recreational areas, school sites, and similar public and semi-public uses with notations of proposed ownership included where appropriate. (Ord. 2016-551 § 2 (Exh. 1); Ord. 2009-417 § 2 (Att. 1). Formerly 18.21.030).