Dedicated landscape water meters are highly recommended on landscape areas smaller than five thousand (5,000) square feet to facilitate water management.

Automatic irrigation controllers utilizing either evapotranspiration or soil moisture sensor data shall be required for irrigation scheduling in all irrigation systems.

The irrigation system shall be designed to ensure that the dynamic pressure at each emission device is within the manufacturer's recommended pressure range for optimal performance.

Sensors (rain, freeze, wind, etc.), either integral or auxiliary, that suspend or alter irrigation operation during unfavorable weather conditions shall be required on all irrigation systems, as appropriate for local climatic conditions. Irrigation should be avoided during windy or freezing weather or during rain.

Manual shut-off valves (such as a gate valve, ball valve, or butterfly valve) shall be required, as close as possible to the point of connection of the water supply, to minimize water loss in case of an emergency (such as a main line break) or routine repair.

Backflow prevention devices shall be required to protect the water supply from contamination by the irrigation system. A project applicant shall refer to the applicable local agency code (i.e., public health) for additional backflow prevention requirements.

High flow sensors that detect and report high flow conditions created by system damage or malfunction are recommended.

The irrigation system shall be designed to prevent runoff, low head drainage, overspray, or other similar conditions where irrigation water flows onto non-targeted areas, such as adjacent property, non-irrigated areas, hardscapes, roadways, or structures.

Relevant information from the soil management plan, such as soil type and infiltration rate, shall be utilized when designing irrigation systems.

The design of the irrigation system shall conform to the hydrozones of the landscape design plan.

The irrigation system must be designed and installed to meet, at a minimum, the irrigation efficiency criteria as described in § 36-24.14 regarding the Maximum Applied Water Allowance.

It is highly recommended that the project applicant or local agency inquire with the local water purveyor about peak water operating demands (on the water supply system) or water restrictions that may impact the effectiveness of the irrigation system.

In mulched planting areas, the use of low volume irrigation is required to maximize water infiltration into the root zone.

Sprinkler heads and other emission devices shall have matched precipitation rates, unless otherwise directed by the manufacturer's recommendations.

Head to head coverage is recommended. However, sprinkler spacing shall be designed to achieve the highest possible distribution uniformity using the manufacturer's recommendations.

Swing joints or other riser-protection components are required on all risers subject to damage that are adjacent to high traffic areas.

Check valves or anti-drain valves are required for all irrigation systems.

Narrow or irregularly shaped areas, including turf, less than eight (8) feet in width in any direction shall be irrigated with subsurface irrigation or low volume irrigation system.

Overhead irrigation shall not be permitted within twenty-four (24) inches of any nonpermeable surface. Allowable irrigation within the setback from nonpermeable surfaces may include drip, drip line, or other low flow non-spray technology. The setback area may be planted or unplanted. The surfacing of the setback may be mulch, gravel, or other porous material. These restrictions may be modified if:

Slopes greater than twenty-five (25%) percent shall not be irrigated with an irrigation system with a precipitation rate exceeding 0.75 inches per hour. This restriction may be modified if the landscape designer specifies an alternative design or technology, as part of the Landscape Documentation Package, and clearly demonstrates no runoff or erosion will occur. Prevention of runoff and erosion must be confirmed during the irrigation audit.

Each valve shall irrigate a hydrozone with similar site, slope, sun exposure, soil conditions, and plant materials with similar water use.

Sprinkler heads and other emission devices shall be selected based on what is appropriate for the plant type within that hydrozone.

Where feasible, trees shall be placed on separate valves from shrubs, groundcovers, and turf.

Individual hydrozones that mix plants of moderate and low water use, or moderate and high water use, may be allowed if:

Individual hydrozones that mix high and low water use plants shall not be permitted.

On the landscape design plan and irrigation design plan, hydrozone areas shall be designated by number, letter, or other designation. On the irrigation design plan, designate the areas irrigated by each valve, and assign a number to each valve. Use this valve number in the Hydrozone Information Table. This table can also assist with the irrigation audit and programming the controller.