City of Frisco Engineering Standards

Engineering Standards
Section 7 – Irrigation Design Requirements
7.01 General
A. The purpose of this section is to provide additional requirements and standards to address
irrigation requirements within the medians of major and minor thoroughfares. Refer to the
following ordinances and documents:
1.
Irrigation Ordinance (HB 1656)
2. Water Management Plan
3. Zoning Ordinance, Section 4.02 – Landscape Requirements
7.02 Roadway Irrigation Requirements
A. Irrigation system shall be designed and installed to minimize runoff onto paved surfaces.
Overspray on streets and walks are prohibited.
B. Private irrigation system mainlines, valves, or control wires located within the City’s right-of-way
shall be maintained by the adjacent property owner.
C. The bore depth under streets, drive aisles, and fire lanes shall allow 2’ minimum from the bottom
of paving to the top of the sleeve, or greater if required to clear other utilities
D. All irrigation piping and boxes shall be purple in color.
E. A separate water meter is required for irrigation.
F. ET controllers shall be installed on AC power.
G. A ball valve is required on the upstream side of control valve and shall be located in a jumbo box.
H. Backflow prevention devices are required for all irrigation systems.
I. Provide a section valve to regulate pressure in the irrigation system.
J. Check valves are required where elevation differences will cause low-head drainage.
K. PVC water lines shall be Pressure Rated Class 200, DR 21.
L. Minimum main line pipe size shall be 1-1/4”.
M. Minimum lateral line pipe size shall be 3/4”.
N. System shall deliver a minimum residual pressure of 30 pswi at the spray head and 50 pswi for
rotors.
O. Each valve shall irrigate a landscape zone containing plant materials with similar water
requirements and similar site, slope and soil conditions.
P. Where drip systems are to be used, they shall be designed to provide water uniformly from subgrade
PVC piping.
Section 7 – Irrigation Design Requirements May 2012 Page 7-2