Chapter III. Materials
Sec. 503-1 PVC Pipe and Fittings
503-1.01 Pressure Main Line Piping and Fittings: Sizes two and one half (2-1/2) inches or larger shall be P.V.C. Class 200 Ring Tite or approved equal.
503-1.02 Pressure Main Line Piping and Fittings: Sizes two (2) inches and smaller shall be Schedule 40 P.V.C.
503-1.03 Non-pressure laterals shall be minimum thickness Schedule 40 P.V.C.
503-1.04 P.V.C. nipples shall be Schedule 80 with molded threads.
503-1.05 All pipe and fittings shall conform to specific requirements as follows:
- P.V.C. Pipe: Manufactured from virgin polyvinyl chloride compound in accordance with ASTM D1784 or ASTM D2241, Cell classification 12454B.
- P.V.C. Fittings (solvent weld or thread): Standard weight, schedule 40, side gated, injection molded P.V.C. complying with ASTM D1784, cell classification 13454B, including threads when required.
Sec. 503-2 Electrical (Low Voltage)
503-2.01 Wiring sizing shall be a minimum of #14 direct burial AWG-UF, 600-volt wire, insulation thickness 3/64 inch, utilizing low density high molecular weight polyethylene insulation. Wiring shall be color coded with the common wire to be white and all others in different colors. An extra wire for every six (6) stations shall be looped in each valve box and housed in a box.
503-2.02 Splices, where necessary or permitted, shall be waterproofed using connectors which are UL 486D compliant.
503-2.03 All wiring placed under concrete or pavement shall be placed in a sleeve with pull boxes at each end.
Sec. 503-3 Gate Valves
503-3.01 Gate valves three (3) inches and smaller: ASTM B62 brass body, 150-pound saturated steam rated; with screwed joints; non-rising stem; screwed bonnet, solid disc. Provide with handwheel.
503-3.02 All gate valves shall be installed with schedule 80 unions to allow easy removal and placed in an approved valve box.
Sec. 503-4 Backflow Prevention Units
503-4.01 Backflow preventer shall be designed to operate on a "reduced pressure" principle; equipped with gate valves, “Wye” strainers of 125# class brass with 40 mesh monel screen and field test cocks acceptable to the water purveyor and the Environmental Health Services Department.
503-4.02 Prior to acceptance, the backflow prevention unit must be tested, and the test results submitted to, and approved by, the Environmental Health Services Department.
The backflow preventer shall be protected by a water protection unit mounted to the concrete slab and shall have adequate insulation blanket attached to the unit.
Sec. 503-5 Automatic Controller
Automatic controllers shall be the fully automatic operation type capable of independently operating the number of stations indicated.
503-5.01 Wall mount type in a housing with locking hinged cover.
503-5.02 Fuse and chassis ground all controller components.
503-5.03 The controller shall be mounted inside a stainless steel, vandal-resistant and weather-resistant enclosure. The enclosure shall include a predrilled backboard with 117-volt duplex outlet. Metal conduit shall run from the 117-volt supply to the controller housing. All power within the housing shall be properly phased.
503-5.04 Controller must be UL approved. Each valve shall be controlled by a separate station.
503-5.05 The electric meter may be installed in the above cabinet or a separate, approved vandal-resistant enclosure.
Sec. 503-6 Remote Control Valves
503-6.01 Valve type shall be spring-loaded, packless diaphragm activated, normally closed type with plastic body, equipped with adjustable flow control.
503-6.02 Valve solenoid shall be 24-volt A.C. 45-watt maximum, 500 milli-amp maximum surge, corrosion-proof, stainless steel construction, epoxy encapsulated to form a single integral unit.
503-6.03 Provide bleeder valve to permit operation in the field without power at the controller.
503-6.04 All valves shall be installed with Schedule 80 unions to provide for easy maintenance.
503-6.05 Identification tags shall be attached to each remote-control valve, showing the number that corresponds with the controller sequence. Tags shall have the station number displayed with one-half (1/2) inch letters.
Sec. 503-7 Small Lawn Sprinkler Heads
Heads shall have screw adjustments.
Nozzles shall rise a minimum of six (6) inches.
Sec. 503-8 Rotary Sprinkler Heads
Rotary sprinkler heads shall be gear driven with minimum six (6) inch pop-up sprinkler heads.
Part circle heads shall have variable arc setting capability.
Sec. 503-9 Quick Coupling Valves
503-9.01 Type: Heavy-duty, brass construction, with stainless steel internal valve spring, using a three-fourths (3/4) inch valve key, and shall have a locking rubber cover.
503-9.02 Quick Coupling Valves shall be spaced no more than 100 feet apart or 50 feet from either end of landscape sections.
503-9.03 All Quick Coupling Valves shall be installed in approved round valve boxes.
Sec. 503-10 Small Shrubbery Sprinkler Heads
12-inch minimum pop-up type body shall be used. Heads shall be fully adjustable.
Sec. 503-11 Valve Boxes
503-11.01 Valve boxes shall be fabricated from a durable plastic material with UV inhibitors, resistant to weather, sunlight and chemical action of soils.
503-11.02 Gate valve boxes shall be round plastic boxes with an overlapping, lockable lid.
503-11.03 Remote control valve boxes shall be rectangular plastic boxes with an overlapping, lockable lid.
Sec. 503-12 Installation - General
503-12.01 All plastic pipe and fittings shall be installed in accordance with manufacturer's instructions for same.
503-12.02 Line Clearance: All lines shall have a minimum clearance of six (6) inches from each other and from lines of other trades. Parallel lines shall not be installed directly over one another.
503-12.03 Pressure lines shall have a metallic detector tape placed above them in accordance with manufacturer's recommendation.
503-12.04 Provide minimum coverage as follows:
Pressure supply lines (two and one half - (2-1/2) inches and smaller): 18 inches
Pressure supply lines (three (3) inches and larger): 30 inches
Non-pressure lines: 12 inches
Control wire: 18 inches
All wire and pipes under concrete or paving shall be at least 30 inches deep and sleeved.
503-12.05 All lines placed under paving or concrete shall be contained in a Schedule 40 P.V.C. sleeve. The size of the sleeve shall be the minimum size which will allow the interior pipe or control wire to be freely removed and replaced.
Sec. 503-13 Field Quality Control - Adjustment of the System
503-13.01 The Contractor shall adjust all sprinkler heads and valves for optimum performance and to prevent as much as possible any overspray onto walks and roadways.
503-13.02 Testing of Irrigation System
Test all pressure lines under hydrostatic pressure of 150 pounds per square inch and prove watertight. Testing of pressure main lines shall occur prior to installation of electric control valves, quick couplers or any other equipment that might prevent a proper test from being performed. All piping under paved areas shall be tested under a hydrostatic pressure of 150 pounds per square inch, and proved water-tight, prior to paving. Pressure in lines shall be sustained for not less than two (2) hours. If leaks develop, replace joints and repeat test until entire system is proven watertight.
Sec. 503-14 Plant Material
503-14.01 Soil
Engineer shall submit to the County for approval a soil nutrient report; this requirement may be waived if the County has on file acceptable information to indicate that it is not warranted. The report shall contain recommendations of soil amendments, fertilizers, as well as an indication of the soil's suitability for the purpose intended.
503-14.02 Plants
Turf will only be allowed under certain circumstances and if in compliance with MWELO, this must be approved by the Director of Public Works. Trees shall not be a type which have a lot of surface roots or drop fruit or are a maintenance problem. Trees when planted near concrete or paving shall be planted with root guards. All plants/trees must be chosen from WUCOLS Database (Water Use Classification of Landscape Species). Trees which exceed a four (4) inch diameter trunk at 10 years growth shall not be placed in the right-of-way without specific approval from the Director of Public Works or his representative. No trees shall be planted within 20 feet of a streetlight pole base.
Sec. 503-15.01 Multi-Use Trail Fence
Trail fence shall be heavy duty two rail white vinyl fence designed for agricultural uses, or an alternative approved by the Engineer. Fence rails shall be nominal two (2) inches x six (6) inches x 16 feet ribbed type, with minimum 0.11-inch wall thickness, installed with a minimum 24” bury at eight (8) feet on center. Use aluminum inserts at all end, corner and gate posts (both latch and hinge sides) or fill with concrete. See Plate No. L-15 for details.
Sec. 503-16.01 Stamped Concrete
Stamped or imprinted concrete shall require proposed design provided and approved with Landscape Plans. Design mix shall include design of stamp or imprinting, color and other relevant specifications. If vapor retarding membrane is not used, the based shall be moistened. Concrete shall be constructed with the use of forms in accordance with ACI 347. Concrete shall be placed in accordance with ACI 301, 302 and 304. If using non-integral color, apply color hardener prior to application of pattern. Apply hardener at rate by that recommended by the manufacturer, evenly to the surface of the fresh concrete by the dry-shake method. If applied in two or more shakes, float after each shake and trowel concrete only after final floating. While concrete is still in its plastic state, apply the tool/texture pattern to the surface of the concrete. Property tamp tools into the surface to achieve the required texture, with uniformity of pattern and depth of stamping. Release materials shall be applied to the troweled surface prior to stamping/imprinting. Place curing compound on exposed concrete surfaces immediately after finishing in accordance with the manufacturer's instructions. If required per design, apply secondary stain treatment and apply finish sealer per approved design. Immediately after placement, protect concrete from premature drying, excessive temperatures and mechanical damage.
