City of Frisco Engineering Standards

B. Mainline and Lateral Piping: Install with 12 inches of soil cover over laterals and 24"
coverage over 8" mainline and 18" coverage over 6" and small mainline.
C. Trenching: Provide firm, uniform bearing for entire length of pipe to prevent uneven
settlement. Wedging or blocking of pipe is not permitted. Remove foreign matter from
inside of pipes before assembly. Keep inside of piping clean during and after layout of pipes.
D. Backfill: Water jet and compact to 90% to prevent after-settling. Hand rake trenches and
adjoining areas to leave grade in condition equal to before installation.
3.04 PVC PIPE AND FITTINGS ASSEMBLY:
A. Solvent: Use solvent and procedures recommended by manufacturer to make solvent-welded
joints. Thoroughly clean pipe and fittings before applying solvent.
B. PVC to Metal Connections: Use Teflon tape.
C. Threaded PVC Connections: Use threaded PVC adapters into which pipe may be welded.
Use Teflon tape on threads.
3.05 ELECTRICAL VALVES:
A. Provide valves in accordance with materials list and size according to plans.
B. Install valves in a level position in accordance with manufacturer's specifications.
C. Provide plastic valve box, centered over valve, flush with finish grade. Provide valve box
extensions as required.
D. Install 0.5 cubic feet washed pea gravel in bottom of valve box.
3.06 SPRINKLERS:
A. General: Provide in accordance with materials list with nozzle in accordance with plans.
Change nozzle degree and trajectory if wind conditions affect coverage. Receive approval
from the Owner prior to any change. Install heads adjacent to walks and curbs 2 inches clear
of paving.
B. High-Pop Shrub Heads: Provide nozzles as indicated in 2.15 twelve (12”) inch pop-up body.
Attach to lateral piping with ½” . . Firmly tamp soil around base plate and leave head plumb.
Underside of flange shall be set flush to 1" above finish grade.
C. Lawn Heads: Attach sprinklers to lateral piping with flex PVC pipe. Firmly tamp soil around
base plate and leave head plumb. Underside of flange shall be set flush to 1/4" above finish
grade in hydro seeded areas and 1" above finish grade in solid sodded areas.
D. Rotary Heads: Install as detailed on the plans on swing joints. Follow manufacturer's
assembly and installation procedure. Set heads flush with finish grade or sod.
3.07 QUICK COUPLING VALVES (QCV): Provide in accordance with materials list and as detailed
on plans. Stake with a 1" galvanized pipe.
City of Frisco May 2012
Standard Technical Specification Irrigation System 328000-9