Blowouts Are Only One Step in Fall Shutdown

By Jon Peters, Founder and General Manager, Irrigation Managers. 33 years in irrigation technology and agronomy.

As of October 6, 2026. Washington's statewide drought emergency covers every watershed in the state and runs through April 7, 2027.

The blowout crews are on the road. Every grounds team knows this job: compressor on, zone by zone, water out. It protects thousands of dollars of pipe, valves and heads, and nobody forgets it.

But a blowout is one step in shutting a system down for the winter. Two other steps get skipped every year, and this year they matter more than usual: capturing what your system did this season, and planning next season while the lessons are still fresh.

Key Takeaways

Washington's drought emergency runs through April 7, 2027, so it will still be in effect when most properties charge their mainlines next spring.[^1]
Save your controller's season history before shutdown. Some controllers keep a full season, some a few weeks, some nothing, and a power-down, firmware update or winter reset can wipe it.
The average installed system runs at about 50 percent distribution uniformity, below EPA's 65 percent minimum.[^6][^7] Extra run time can't fix mismatched heads and nozzles.
A season's total water can look right and still be wrong. When the water goes on matters as much as how much.
Fall is planning season. Repairs and upgrades like flow sensing and remote access are easiest to make over winter, before startup.

Why Is This Fall Different?

Washington is under a statewide drought emergency that runs through April 7, 2027, and a strong El Niño winter could mean below-normal snowpack in Spokane. Properties that know their numbers before spring will be in the best position for a second dry year.

On April 8, 2026, the Washington Department of Ecology declared a drought emergency for every watershed in the state, and the order runs through April 7, 2027.[^1] That means it will still be in effect when most properties charge their mainlines next spring. As of September 22, 93.57 percent of Washington was in moderate drought or worse, and most of Spokane County moved to extreme drought (D3) in August.[^2][^3]

NOAA puts the odds of a very strong El Niño this winter at better than 90 percent.[^4] In Spokane, El Niño winters have averaged about 72 percent of normal snowfall, though the National Weather Service is clear that is not a guarantee.[^5] Nobody can promise a dry 2027. But the properties that come through a second dry year in good shape will be the ones that knew their numbers before the season started.

What Should You Save From Your Controller Before It Goes Dark?

Before shutdown, pull the season's run times, water applied, flow readings, alarms and manual overrides, and save them somewhere other than the controller. Many controllers keep little or no history, and a reset can erase what they have.

Before the controller goes dark, pull what it knows and save it somewhere other than the controller:

Run times by zone, by month
Total water applied, from your irrigation meter or utility bills
Flow readings, alarms and faults
Manual overrides

How much history a controller keeps varies a lot by make, model and settings. Some keep a full season, some keep a few weeks, and some keep nothing at all. A power-down, a firmware update or a winter reset can wipe what is there. Check yours now, not in March.

What Should Your Crew Write Down Before Winter?

Walk the site while the season is fresh and log every problem zone by number, with photos. Check that heads and nozzles match within each zone, because mismatched equipment is one of the most common causes of poor uniformity.

Walk the site with your crew while the season is fresh and log the zones that gave you trouble, by zone number, with photos. The cause could be programming, a wiring or pipe problem, construction on the site, or the zone itself. You do not have to solve it today. You just have to write it down before April, when nobody remembers which zones they were.

While you are walking, look at the heads. Are the heads in each zone the same type? Do the nozzles match, so every head puts down water at the same rate? In my experience, the average installed system runs at about 50 percent distribution uniformity, which matches what the Irrigation Association found across more than 6,800 audits.[^6] EPA guidance calls for at least 65 percent.[^7] Mismatched heads and nozzles are one of the most common reasons, and no amount of extra run time fixes them: the only way a schedule can keep the dry spots green is to overwater everything else.

Definition — distribution uniformity: Distribution uniformity (DU) is a measure of how evenly a sprinkler zone applies water, comparing the driest quarter of the zone to the zone's average.

If you already know a zone needs work, make the fix first and then record the data from the corrected zone. That is the number worth having. On a zone that is already performing well, measuring its distribution rate and uniformity gives you solid numbers to program from next season.

Don't forget the trees

One more thing while it is on your mind: trees. Lawn heads do not water deep root zones, and WSU Extension recommends a deep watering for trees in late fall, after leaves drop and before the ground freezes.[^8] After a summer like this one, put it on the calendar.

Before spring startup: know your number

A second dry year rewards the properties that planned for it. A water use analysis gives you measured water need, peak demand, and seasonal adjustment for every zone, ready before your mainlines are charged.

Request a water use analysis for your site →

How Do You Plan Next Season During Fall Shutdown?

Compare the water you actually applied this season to what your landscape needed, using local evapotranspiration (ET), rainfall and your irrigated area. Then use the winter to make repairs and plan upgrades before startup.

Fall is planning season. Start by comparing the water you actually applied this season to what your landscape needed. To estimate the need, take this season's reference evapotranspiration (ET) and rainfall for your location, and multiply by your irrigated area in square feet. You can look up ET and rainfall for any location with our free ET and rainfall lookup tool. Without the irrigated area, the comparison does not work, so measure it if you do not know it.

Definition — reference evapotranspiration (ET): Reference evapotranspiration is the amount of water a standard reference surface loses to evaporation and plant transpiration over a period of time, calculated from local weather data.

Winter is also the easy time to make repairs and plan upgrades, like flow sensing and remote access, so they are in place before startup.

Why Does Timing Matter as Much as the Season Total?

A season's total can match what the turf needed and still fail it. Too little water in spring dries the soil going into summer, and on larger systems there is often not enough capacity to catch up during peak heat.

Look at when the water went on, not just how much. The season's total can look right and still be wrong. We worked with a park whose season total was close to what the turf needed. The problem was timing: they went on light in the spring, the soil dried out going into summer, and they could never catch up. Then they put down far too much in the fall. The park looked good in spring, looked terrible all summer, and started to recover in late fall, which is the opposite of what anyone wanted.

Why Do So Many Sites Fight the Same Problems Every Summer?

Most sites overwater, and many irrigate reactively: they wait for the turf to brown, then try to catch up. Getting ahead of demand in spring is what breaks the cycle.

Most sites I see use at least double the water their plants need. Some properties are more careful than that, but even then, the hardest part is getting water on at the right time. Many irrigators are reactive. They wait until the turf goes brown, then try to catch up, and on larger systems there often is not enough capacity to bring dry soil back up to where the plants need it during the hottest part of the year. If you do not get ahead of it in the spring, you fall behind, and you fight the same problems every summer.

A blowout protects the pipe. The data and the lessons protect next year. Take an hour this fall to save what your controller knows and write down what your crew saw, and spring startup begins with a plan instead of last year's program.

What Should Grounds Teams Do Before the Ground Freezes?

☐ Export the controller's season history — run times, flows, alarms, overrides — and save it off the controller.
☐ Pull total water applied from the irrigation meter or utility bills.
☐ Walk the site with your crew and log problem zones by number, with photos.
☐ Check heads and nozzles for matches in every zone; fix known problems, then record the corrected zone's data.
☐ Deep-water trees after leaf drop and before the ground freezes.
☐ Compare water applied to water needed using ET, rainfall and irrigated area.
☐ Get repairs and upgrades into the budget conversation. Municipal parks budget July–June with capital projects in Q1; HOAs and commercial campuses draft next year's budget this fall; K-12 and higher ed proposals generally need to be in by March.

How Irrigation Managers Can Help

We build a water use analysis for your site: measured water need, peak demand, and seasonal adjustment for every zone, ready before spring startup instead of during a July emergency. In Liberty Lake, two city parks managed this way are on track to use 25 to 30 percent less water in 2026, in a drought year, with consistent, healthy turf across every zone.

Request a Water Use Analysis →

Frequently Asked Questions

Is a blowout enough to winterize an irrigation system? A blowout protects pipe, valves and heads from freeze damage, but it is only one step in a complete fall shutdown. The other two are saving the season's controller data (run times, water applied, flow readings, alarms and overrides) and recording which zones had problems while the crew still remembers. Those two steps are what let you start next spring with a plan instead of last year's program.

Will Washington's drought emergency still be in effect next spring? Yes. The Washington Department of Ecology's drought emergency, declared April 8, 2026, covers every watershed in the state and runs through April 7, 2027, after most properties start their irrigation systems. A strong El Niño winter has historically meant below-normal snowfall in Spokane, though the National Weather Service notes that is not a guarantee.

Why does my landscape have dry spots even though I added more run time? Usually because of poor distribution uniformity, not too little water. The average installed system applies water at about 50 percent uniformity, below the 65 percent minimum in EPA guidance. Mismatched heads and nozzles are a common cause. Adding run time keeps the dry spots green only by overwatering the rest of the zone, so the fix is matching the equipment, then programming from the corrected zone.

Why did my turf struggle all summer when our total water use looked right? Because timing matters as much as volume. If a site goes on light in spring, the soil dries out heading into summer, and larger systems often lack the capacity to catch up during peak heat. Comparing monthly water applied against monthly ET shows whether the water went on when the plants needed it.

References

[^1]: Washington State Department of Ecology, Drought 2026 Order and Determination, April 8, 2026. https://ecology.wa.gov/getattachment/40b0a4a1-efc8-4326-9d51-bbfc4cab6e54/Drought-2026-Order-and-Determination.pdf

[^2]: U.S. Drought Monitor, Washington, valid September 22, 2026. https://droughtmonitor.unl.edu/Data/pdf/current/current_WA_cat.pdf

[^3]: Office of the Washington State Climatologist, September 2026 Drought and Streamflow Update, September 10, 2026. https://climate.uw.edu/2026/09/10/september-2026-drought-and-streamflow-update/

[^4]: NOAA Climate Prediction Center, ENSO Diagnostic Discussion, September 10, 2026. https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

[^5]: National Weather Service Spokane, El Niño and the Inland Northwest. https://www.weather.gov/otx/elnino

[^6]: Brent Mecham, Using Distribution Uniformity to Evaluate the Quality of a Sprinkler System, Irrigation Association, 2004. https://www.irrigation.org/IA/FileUploads/IA/Resources/TechnicalPapers/2004/UsingDistributionUniformityToEvaluateTheQualityOfASprinklerSystem.pdf

[^7]: U.S. EPA, WaterSense at Work, Section 5.3: Irrigation, 2023. https://www.epa.gov/system/files/documents/2023-05/ws-commercial-watersense-at-work_Section_5.3_Irrigation.pdf

[^8]: WSU Extension Master Gardeners, Trees in Fall. https://wpcdn.web.wsu.edu/extension/uploads/sites/74/2018/12/Trees-in-Fall-from-WSU-Extension-Master-Gardeners-1.pdf