Irrigation Winterization Procedure Davis Campus

Procedure Number: OP07
Issue Date: January 23, 2012
Last Revision Date: January 23, 2012

Irrigation Winterization Procedures for WSU Davis Campus and
Continuing Education Building

This document provides a concise, comprehensive process for irrigation winterization and
seasonal maintenance by Facilities Management on Weber State University Davis Campus.

Irrigation Plans for WSU Davis Campus LI101, LI102

Automatic Irrigation System: Irrigation systems that do not require a manual turn on and shut off
from the site box.
Computerized maintenance management system (CMMS): Database that Facilities Management
uses as a work management system.
Manual Irrigation System: Irrigation systems that require a manual turn on and shut off from the
site box.

Responsible Party:
Facilities Management Landscape personnel 

Facilities Management will support and maintain a sustainable winterizing procedure for
irrigation systems at Weber State University’s Davis Campus. An annual evaluation of current
practices will be performed to accommodate upgrades and changes in the irrigation systems.
Beginning October 1, a Preventive Maintenance work request will be flagged in the CMMS to
indicate the commencement of the winterization process. Irrigation systems will be attended
beginning from the highest point of elevation for the campus. The following procedures will be
completed after October 15, annually:


A. Before Beginning Winterization
1. Reserve a “185” compressor from list of vendors by September 1 (earlier reservation
dates are preferred).
2. Ensure that a 50 foot compressor hose is included in the compressor rental.
3. Procure any attachments and connectors necessary for this process.
4. Schedule out one whole day for blowing out lines.

B. Procedure for Draining
1. Ensure that the Weber Basin Water line is shut down and off for the season (contact
Weber Basin Water, 2837 East Highway 193 in Layton, UT 84040, 801-771-1677
with questions).
2. Shut off butterfly valves located at filter in the Northeast field in the gated area. To
access the filter, return to 3000 N, drive east and turn onto 725 W, drive south until
the road ends. The irrigation technician will leave the vehicle and walk to the
northeast corner of the field where the enclosed filter is located.
3. Drain in two different spots to remove water from main line: The SW area and a drain
valve in the SE corner just SW of the landscape shed.
4. Open up the B18 or B19 valves (crack open and drain out moderately). Those lines
will be allowed 2-3 days to drain out system, this is to avoid flooding.
5. Close the 2” valve and B18 and B19 valves before blowing out the line otherwise
they will not pressurize enough to expel the water.
6. On each head for the Drip System, remove drip system filters.
7. Reconnect all filter housing to ensure full system blow out success.

C. Blowing Out Irrigation Lines
Begin at the highest elevation point on campus (A1 valve). Allow the irrigation lines to
lines drain down during blow out period.
1. Pick up compressor from designated vendor.
2. Connect the compressor to the quick connect located inside the irrigation box that is
shared with the C7 valve
3. Insert disconnect into quick coupler. The C7 valve is removed from the main
buildings and will cause as little disturbance as possible to WSU personnel. 
4. Every valve must be run through until only air is being expelled.
5. Open up the drip system. Leave each one on for 5 minutes. The drip system will not
mist, so this amount of time for them to be open is vital to prevent water retention and
sub sequential freezing.
6. After all valves have been run through and properly blown out, disconnect
compressor and prepare to return to vendor.

D. Returning Rented Equipment
1. Ensure all rented equipment is accounted for and packed properly.
2. Make arrangements with the Davis Campus Superintendent for a supervisor’s gas
card to be used to refuel the rented compressor.
3. Return compressor and rented equipment to the vendor.

E. Follow up and Completion of Winterization

1. Clean drip system filters and return to housing (up to 30 filters).
2. Open every manifold drain. These are to be left open at a 45 degree angle all season
(located in the circular vents).
3. Leave the air vents open all year long.
4. Open up butterfly valves on main filter.
5. Disconnect the tubing from the blow down solenoid (leave open for the season).

F. Maintenance
Winter irrigation system maintenance will include the following:
1. Before the winterization process begins, a work request must be flagged and activated
for the irrigation crew to trim around irrigation boxes.
2. All irrigation maintenance during the season will be handled by the Facilities
Management Ogden Landscape department.


The following procedure will be followed for winterizing the Continuing Education property for

A. Before Beginning Winterization
1. Reserve a compressor from list of vendors by September 1st or earlier.
2. Ensure that a 50 foot compressor hose is included in the compressor rental
3. Procure any attachments and connectors necessary for this process

B. Procedure
1. Park compressor near northeast corner of Continuing Education building, in the
north utility access.
2. Isolate system- The stop and waste valve is in the north planter bed by front door.
3. Connect compressor into 3/4" quick connect in plastic irrigation box at northeast
side of Continuing Education building. 
4. There are many drains on the main line, at multiple valve boxes. The mainline
feeding the backflow preventer drains back through the stop and waste valve.
5. Turn on each station until the last head is misting.
6. Blowout backflow preventer (double-check valve) in the north planter bed by
opening the test clocks.
7. Keep isolation closed until spring irrigation start-up.