Installation specifications shall be indicated whenever possible. Installation shall conform to the City approved irrigation details included herein.
The irrigation system shall be organized into zones based upon plant material selections and environmental considerations (i.e. sun exposure, slope aspect, soil conditions, etc.)
The selection of irrigation systems components shall be based upon the overall design and upon water conservation principles. A minimum of 25% of each landscape shall be irrigated with low volume systems. The designer shall indicate on the irrigation plan the proposed water management principles.
The irrigation system must provide complete coverage for all areas (head to head coverage when spray heads are used). Closer spacing may be required due to climatic and site conditions (i.e. areas of excessive wind).
Where above ground irrigation components (such as automatic controllers and backflow devices) are placed on slopes, low retaining walls and/or curbing shall be required to prevent erosion.
The backflow prevention device shall be a reduced pressure backflow installed at least twelve (12) inches above grade, measuring from the bottom of the device.
The backflow device shall be winterized/wrapped with a Thermo-cel insulation tape to R-I0 protection and enclosed in a locking LeMeur Steel enclosure or equal mounted on a concrete pad. The risers shall be galvanized steel.
The contractor shall provide a padlock and two keys (per City standards) for each steel enclosure.
Pressure supply lines downstream of the backflow prevention device shall be Class 315 PVC in sizes 2" and larger and Schedule 40 PVC in sizes 1-1/2" and smaller. Non pressure lines shall be scheduled to be 40 PVC.
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