Urban Flood Irrigation in Glendale: How It Works
Glendale still delivers flood irrigation to many downtown lots. Learn how the city's urban irrigation schedule works, how to prepare, and how it fits with drip.
Irrigation Guides5 min read
Glendale still delivers flood irrigation, raw Salt River Project water, to many lots in the downtown area through its urban irrigation system. In 2026 deliveries began April 6, with ten sections each served about every two weeks through late October, between 5 a.m. and 6 p.m.
Most of Glendale waters its yards with sprinklers and drip on city tap water. A part of the old town still does it the way the whole valley once did: by flooding the yard with canal water on a schedule. This guide explains what Glendale's urban irrigation is, how the schedule works, how to prepare, and how it fits with a sprinkler or drip system on the same lot.
What is urban flood irrigation in Glendale?
Urban irrigation is the direct delivery of untreated Salt River Project water to lots in built-up areas for outdoor landscaping. In Glendale it reaches many lots in the downtown area through open or underground ditches. The water floods a bermed yard on a set day, soaking trees and lawns deeply.
The City of Glendale Water Services page calls it a remnant from an earlier era. It notes that the vast majority of Glendale customers now receive only treated city water, but that the mature landscaping in the older part of town gives that area its distinct character, and it credits urban irrigation for that.
Why does Glendale still have flood irrigation?
Because the city was built on it. W.J. Murphy built the Arizona Canal between 1883 and 1885, which opened farmland northwest of Phoenix, and Glendale's first town site followed in 1892. Flood irrigation from canal water was how that farmland, and later its yards, were watered.
The city's Envision Glendale 2040 General Plan says the city provides urban flood irrigation in the historic district to promote mature vegetation downtown, and includes a policy to preserve and maintain the system with fair rates. As the city grew, developers elsewhere chose for or against it, and many owners whose lots once had it chose to discontinue it.
How does the delivery schedule work?
The city publishes a delivery schedule each year. For 2026 it divides the system into ten sections. Each section has its own weekday, and its delivery comes around every two weeks.
The 2026 urban irrigation delivery schedule shows:
| item | 2026 |
|---|---|
| first delivery | April 6 |
| sections | ten, each on a set weekday |
| frequency | about every two weeks per section |
| last deliveries | late October, through October 30 |
| delivery hours | between 5 a.m. and 6 p.m. |
The city's map shows which streets fall in each section. Billing questions go to the city's billing services and maintenance questions to Water Services, as listed on the city's flyer.
How do I prepare for a flood irrigation delivery?
Get the yard ready before your section's delivery day. The city's 2026 flyer asks owners to cut the grass and remove objects, clear access to the irrigation valve, and secure pets so the person delivering the water can work safely. A contracted zanjero, the traditional name for the person who opens the gates, delivers the water.
Practical extras help too. Check that berms around the yard are intact so water stays on your lot. Move hoses, toys and furniture off the flood area. And turn off any sprinkler zones that cover the same ground on delivery day, so the yard is not watered twice.
Living with flood irrigation and a sprinkler system
Many flood-irrigated lots also have a sprinkler or drip system on city water for the front strip, beds or the weeks between deliveries. The two systems are separate. The flood valve and ditch carry raw canal water, while the sprinkler system runs from the drinking water line through a backflow assembly.
A few things follow from that:
- Do not confuse the pipes. Before digging for a sprinkler repair, know where the flood valve and any underground ditch line run. See pipe repair in Glendale.
- Schedule around delivery days. Pause sprinkler zones that water the flooded area the day before and after.
- Standing water on a delivery day is normal. It is not a sprinkler leak.
- The winter gap. Deliveries stop in late October and restart in spring. Trees that drink from the floods all summer need the sprinkler or drip system to cover them in the cool months.
Flood irrigation and trees
Flood water suits trees well because it soaks a wide area deeply. The University of Arizona citrus irrigation guide notes that flood irrigation works well in established neighbourhoods, and recommends basins about 4 to 8 inches high around the canopy edge. It also says to wet soil from the trunk to just beyond the drip line, at least two feet deep, which is what a good flood does. Our citrus watering guide has more.
Giving up flood irrigation
Some owners drop urban irrigation, and the city confirms many have. If you are thinking about it, ask Water Services how to stop service and plan the replacement first. Trees used to deep flood water have wide roots. A drip system for them needs emitters spread to the canopy edge and long enough run times to reach depth, usually on its own valve. See zone expansion in Glendale and drip irrigation in Glendale, and compare methods in drip versus sprinkler.
FAQ
How do I know if my Glendale lot has flood irrigation?
- Check your water bill and the city's urban irrigation delivery schedule and map, which show the sections served. Lots that take it usually have a flood valve at the edge of the yard and earth berms. Many such lots are in the downtown area, and Water Services can confirm.
When does Glendale flood irrigation start each year?
- In 2026 the City of Glendale started urban irrigation deliveries on April 6. Each of ten sections is served on a set weekday about every two weeks, with the last deliveries in late October. Check the city's current schedule each year, as dates change.
What time does the flood irrigation water arrive?
- The city's 2026 schedule says service occurs between 5 a.m. and 6 p.m. on your section's delivery day. Have the yard ready beforehand: grass cut, objects cleared, the irrigation valve reachable and pets secured, as the city's flyer asks.
Is flood irrigation water safe to drink?
- No. Glendale describes urban irrigation as non-potable, raw and untreated Salt River Project water for outdoor landscaping. It travels in ditches separate from the drinking water system. Keep it for the yard, and keep children and pets from drinking the standing water.
Should I run my sprinklers on a flood irrigation day?
- No. Turn off any sprinkler or drip zones that water the flooded area on delivery day and for a day or two after, so the yard is not watered twice. Keep zones that water areas the flood does not reach on their normal schedule.
Sources
- City of Glendale Water Services page glendaleaz.gov
- Envision Glendale 2040 General Plan glendaleaz.gov
- 2026 urban irrigation delivery schedule glendaleaz.gov
- University of Arizona citrus irrigation guide extension.arizona.edu