§ 60.231. Irrigation Design.

Irrigation system plans and specifications shall identify the proposed equipment, materials and the methods of construction.

(a)

General Requirements.

1.

Turfgrass. Irrigation zones for turfgrass areas shall be separate from irrigation zones for tree, shrub and ground cover beds. It is encouraged that turf be placed on a separate watering program.

2.

Trees. Flood bubblers are preferred for newly installed on-site trees, and required for street trees in new subdivisions or any non-residential site until the trees is established for a minimum of two years.

3.

Shrubs and Ground Covers. The use of low-volume, emitter, multi-trajectory rotating stream nozzles, or target irrigation is preferred for shrubs and ground covers.

(b)

Equipment.

1.

Controllers.

a.

One-family and Two-family Lots. One-family and two-family residential irrigation systems shall incorporate either evapotranspiration (ET) weather-based controllers; soil-moisture sensors and controllers; or an automatic controller that can be annually programmed for monthly variations in water requirements.

b.

Multifamily and Non-Residential Development. Evapotranspiration weather-based controllers, or soil-moisture sensors are required on automatic irrigation systems which use potable water or wells as the water source on all multifamily and non-residential sites equal to or greater than 0.50 acres. Sites less than 0.50 acres may opt to utilize an automatic controller that can be annually programmed for monthly variations in water requirements or a greater water saving technology. Where soil-moisture sensors are used to satisfy these requirements, at least 1 sensor shall be used for each different watering need or microclimate zone in the landscape. For example, if the landscape has 2 areas of ground cover in full sun and 1 in shade, 2 soil-moisture sensors are required.

2.

Flow Sensors. Flow sensors and master valves with a controller capable of monitoring flows (or other leak-detection equipment) shall be required on irrigation systems for multifamily and non-residential developments greater than 5 acres in size. Irrigation heads with built-in water shut-off devices are encouraged.

3.

Spray Heads. All irrigation spray heads shall incorporate pressure-compensating nozzles. Rotary heads and fixed pattern spray heads shall not be installed in the same zone.

4.

Check Valves. Low-lying areas near water bodies and areas with poor drainage shall have heads with check valves.

5.

Impact Sprinklers. Impact sprinklers shall not be permitted, except for sports fields, parks, agricultural uses and golf courses.

6.

Water Velocity. Application rates for all sprinklers and emitters shall be matched within each irrigation zone, but water velocities shall not exceed 5 feet per second.

(Ord. No. 2013-74, § 1, 12-9-2013, Doc. #1312091207)