Forty head of cattle can pull more water out of the ground in a single July afternoon than your house uses all week, and the law says you can pump every gallon of it without a permit. That surprises a lot of people who just bought acreage around Wenatchee planning to run a few animals.
Livestock well water demand is a different animal than sizing a well for a house. The gallons per day rarely look scary on paper. The trouble shows up in bursts, when three stock tanks and a washing machine all want water at the same time and your fifty-year-old well and pump were never built for that moment. This guide covers the real per-head water figures for cattle, horses, sheep, and poultry, how Washington’s stock-water exemption actually works, and what to check before you add animals to a well that’s already carrying a house.
We’re Wenatchee Well Pros. We service wells, pumps, and pressure systems for small ranches, horse properties, and backyard homesteads all over Chelan, Douglas, and Grant counties, and livestock demand is one of the most common reasons a well that worked fine for years suddenly can’t keep up. If you’re adding animals to an existing well, or buying a property with stock water needs already established, call us at (509) 300-5151 and we’ll walk through what your setup can actually handle.
How Much Water Livestock Actually Need Per Day
Every species has its own baseline, and heat and production stage push the real numbers well past the baseline. These are typical daily intake figures used by extension and agricultural sources; treat them as planning numbers, not a guarantee for your specific animals.
| Animal | Typical Daily Intake (per head) | Peak Summer or Production Notes |
|---|---|---|
| Beef cattle, dry or growing | 6-15 gallons | Can climb toward 20 gallons on a 95-degree day |
| Dairy cow, lactating | 20-30 gallons | 40-50 gallons a day is common at peak production and peak heat |
| Horse | 8-12 gallons | 15-25 gallons for a horse working hard or standing in full sun |
| Sheep or goat | 1-3 gallons | Up to 3-4 gallons in extreme heat, lactating ewes and does run higher |
| Swine | 3-6 gallons | Lactating sows can take 6-8 gallons |
| Poultry (chickens, per bird) | 0.05-0.1 gallon | Roughly doubles in a heat wave; a 100-bird flock still totals just 5-10 gallons |
A few things jump out once you run the numbers for a real property. A dozen horses at 12 gallons each is only 144 gallons a day, less than half of what a family of four uses inside the house. A flock of laying hens barely registers at all. Cattle and dairy cows are where the daily totals start to matter, especially in a summer heat spell when intake can jump 40 to 60 percent above a mild-weather day.
The USGS overview of livestock water use covers how these categories add up at a regional scale if you want the bigger picture behind the per-head numbers.
Washington’s Stock Water Exemption: No Gallon Cap, But Not No Rules
Here’s the part that surprises new landowners the most. Under RCW 90.44.050, Washington’s groundwater permit exemption covers four separate categories of use, and stock watering is the only one with no daily gallon limit at all. Domestic use tops out at 5,000 gallons a day (3,000 in some regulated basins under the 2018 Streamflow Restoration law), and industrial use caps at 5,000 gallons a day too. Stock water has no cap, full stop.
The Washington Department of Ecology’s water rights overview explains how the exemption fits into the broader permit system. We cover all four exempt categories in detail in our guide to permit-exempt wells in Washington, including how the domestic cap plays out for a typical house.
That doesn’t mean livestock water is unregulated. A few things still apply:
It’s still a real water right. Stock water drawn under the exemption carries a priority date and can be curtailed in a serious drought like any other right, just like the domestic and irrigation exemptions. Our water rights basics for Washington wells article covers how priority dates and drought curtailment actually work.
Mixed-use wells track separately. If the same well serves your house and your stock tanks, the 5,000-gallon domestic cap applies only to the house side. The stock-water portion isn’t added to that total and isn’t capped on its own. You’re not filing separate paperwork for each use, but it helps to know which gallons are which if a basin ever gets into drought curtailment or a dispute over senior and junior rights.
Scale still matters in practice. The exemption was written with family-scale operations in mind. A genuinely commercial dairy or feedlot can trigger other environmental review, like water quality and waste-handling rules, that have nothing to do with the water withdrawal itself. If you’re planning something bigger than a hobby herd, a call to Ecology’s regional office before you commit is cheap insurance.
The bottom line: the law almost never limits how much water you can give your animals. Your well’s actual yield and your pump and tank’s capacity are the real ceiling, and that’s a plumbing and hydrology question, not a legal one. Request a free estimate if you want an honest read on what your current setup can support before you add animals to it.
From Head Count to GPM: Sizing Your Well and Pump for Livestock
Daily totals are the wrong number to size a well around. Gallons per minute, or GPM, is what actually matters, because stock tanks don’t sip water evenly across 24 hours. They sit full until a float valve drops, then they call for a burst of flow all at once.
Take a property running 40 head of beef cattle and 6 horses off the same well that already serves the house. At 12 gallons a day average for the cattle and 12 gallons a day for the horses, that’s 480 gallons plus 72 gallons, or 552 gallons of stock water on top of a household’s usual 300 to 400 gallons. Total daily draw: under 1,000 gallons. That’s a rounding error against the uncapped stock allowance and comfortably under even the tighter 3,000-gallon domestic limit that only applies to the house anyway.
The real question is what happens when three float valves open in the same 20-minute window on a hot afternoon while someone’s running the washing machine inside. Your pump has to deliver enough sustained flow to refill every tank plus the house fixtures right then, not gently over a full day. A well that tests fine on paper can still leave you with a trickle at the kitchen sink if the pump and pressure tank were sized for a house alone.
Hank Delgado runs cattle on 300 acres outside Moses Lake and grew his herd from 20 to 45 head after buying an adjoining parcel in 2024. He’d read that stock water had no gallon cap and figured that settled the question. It didn’t. His well was drilled in the 1970s for the house and tested at 8 GPM sustained, and once three stock tanks and the house started competing for water on summer afternoons, recovery between draws got slow enough that the pressure tank was cycling constantly.
Rather than drill a new well, we added a 2,500-gallon storage tank with a small booster pump for about $9,500. The well fills the tank steadily around the clock, and the booster handles the bursts the well alone never could.
If you’re not sure what your well can actually sustain, our well yield test guide explains how a real test works and what a normal number looks like for wells around here. Guessing based on a neighbor’s well or a decades-old driller’s log is how people end up surprised mid-summer.
When Multiple Stock Tanks (and the House) All Want Water at Once
Most livestock water problems aren’t about the well running dry. They’re about the pump and pressure tank not being sized for simultaneous demand from float valves scattered across a property.
A standard residential pressure tank and a 3/4 to 1 HP pump are built around a house’s usage pattern: a shower here, a load of laundry there, spread out over the day. Add four or five stock tanks with float valves that can all open within minutes of each other, and that same pump and tank combination starts short-cycling, which wears out the pressure switch and the motor faster than normal use ever would.
The Ostrander family runs a small horse boarding operation near Cashmere and took on four additional boarders in 2025, bringing their total to ten horses across four pasture tanks. House pressure would drop to a trickle whenever laundry ran at the same time a tank refilled, and their pressure switch had already started chattering under the extra cycling. We replaced the undersized pressure tank and switch with a properly sized system for about $1,650, and the short-cycling stopped completely. No new well was needed, just equipment matched to the actual demand pattern.
Storage solves the timing mismatch when a well’s sustained yield is genuinely tight. A tank that fills slowly around the clock and a booster pump that delivers strong flow on demand let a modest well support a herd size it could never handle directly. It’s almost always cheaper than drilling a second well, and it’s often the fix when a well tests fine for a house but struggles once several stock tanks get added. If your pressure tank is original to the house and you’re adding animals, that’s worth checking before the tank becomes the bottleneck.
Small flocks and hobby herds run into the same pattern on a smaller scale. The Callahan family keeps 30 laying hens, a dozen sheep, and two dairy goats on five acres near East Wenatchee and called us worried they might be violating their well’s legal limits. They weren’t close. Their actual issue was a worn pressure switch that had started short-cycling every time the poultry waterer topped off, a $430 repair that had nothing to do with water rights and everything to do with an aging part.
Buying, Selling, or Expanding: Water Rights and Relinquishment for Stock Water
Stock water rights carry the same relinquishment risk as any other water right in Washington. If a property’s stock-water use stops for five consecutive years without a documented, legally recognized reason, the state can treat that portion of the right as relinquished, even though the gallon limit itself was never capped. This comes up most often on land that changes hands after an owner sells off a herd or retires from ranching.
If you’re buying acreage specifically to run livestock, don’t assume a well that “used to water cattle” still carries an active, defensible stock-water history. Ask for the well log, ask how recently animals were on the property, and if the gap is long, get the use history checked before you count on that water for a new herd. Our water rights basics for Washington wells article covers priority dates and the five-year relinquishment rule in more depth, and it’s worth reading before you make an offer on ranch or pasture land.
Selling works the other way. If you’re the one stepping away from livestock, keeping some documented use of the stock-water right, even a reduced herd, protects the water right’s status for whoever buys the place next. A quick conversation with Ecology’s regional office is a lot cheaper than a relinquishment dispute down the road.
Whatever stage you’re at, the well and pump side is where we can help directly. Request a free estimate or call (509) 300-5151 if you’re evaluating a property before you buy, sizing a system before you expand a herd, or just tired of watching your pressure drop every time a stock tank refills.
Frequently Asked Questions
Is there really no limit on how much water I can pump for livestock in Washington?
Under RCW 90.44.050, stock watering is one of four permit-exempt groundwater uses, and it’s the only one without a daily gallon cap. Domestic use is capped at 5,000 gallons a day (or 3,000 in some regulated basins), but stock water has no equivalent limit for a typical family-scale operation. Your well’s actual yield and your pump and tank’s capacity, not the law, are what actually limit how much water your animals can get.
How much water does a horse actually drink in a day?
A horse at rest in mild weather typically drinks 8 to 12 gallons a day. That number climbs to 15 to 25 gallons for a horse working hard, nursing a foal, or standing in full summer sun for extended periods. A small string of horses rarely stresses a well’s daily total, but several stock tanks refilling at once can still stress your pump’s peak flow rate.
Do I need a bigger well or just a bigger pressure tank if my animals are outrunning my water pressure?
Start with a real sustained yield test rather than guessing. If the well itself produces plenty of water but pressure drops when several stock tanks and the house draw at once, the fix is usually a properly sized pressure tank, pump, or added storage, not a new well. If the yield test shows the well genuinely can’t sustain the flow you need, storage with a booster pump is typically far cheaper than drilling a second well.
Can I lose my stock water right if I stop raising animals for a few years?
Yes. Like any permit-exempt water right in Washington, stock water use can be relinquished after five consecutive years of nonuse without a legally recognized reason. If you’re buying land specifically to raise livestock, check how recently the property actually had animals on it before assuming the water right is fully intact.
Wenatchee Well Pros services well pumps, pressure tanks, and water systems for ranches, horse properties, and small homesteads throughout Wenatchee, East Wenatchee, Cashmere, Leavenworth, Chelan, Quincy, and Moses Lake. Licensed and insured in Washington. Free estimates, straight answers, and 24/7 emergency well service when the water stops.