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Water Rights/Case Library

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Coffin v. Left Hand Ditch Co., 6 Colo. 443 (1882)

Why this matters: Colorado didn’t just prefer prior appropriationprior appropriationThe western US rule. Whoever first took water and put it to use has the strongest claim, no matter where their land sits. The shorthand is "first in time, first in right.", it declared that riparian rightsriparianThe eastern US rule, and Wisconsin's rule. If your land touches a lake or stream, you get reasonable use of that water, shared with everyone else whose land touches it. The rights come with the land and generally cannot be sold separately from it. never existed there at all. This is the purest version of western water law. It also blessed moving water out of its home watershed, which is the legal seed of every long-distance pipeline argument since.

Doctrine: Prior appropriationprior appropriationThe western US rule. Whoever first took water and put it to use has the strongest claim, no matter where their land sits. The shorthand is "first in time, first in right." (the “Colorado doctrine”)

Case name and citation

Coffin v. Left Hand Ditch Co., 6 Colo. 443 (1882).

Court and year

Supreme Court of Colorado. Decided 1882. Opinion by Justice Helm.

One-line holding

Riparian rightsriparianThe eastern US rule, and Wisconsin's rule. If your land touches a lake or stream, you get reasonable use of that water, shared with everyone else whose land touches it. The rights come with the land and generally cannot be sold separately from it. never applied in Colorado, and the first appropriator of water for a beneficial usebeneficial useActually using water for something productive: farming, drinking, industry, and in most western states now, keeping fish alive. In the West it is what earns you a water right and what caps how much you get. holds a prior right even when the water is carried across a divide into a different watershed.

Facts

Left Hand Ditch Co. diverted water from the south fork of the St. Vrain Creek. It carried that water by ditch to James Creek, down James Creek to Left Hand Creek, and then out through lateral ditches to irrigate farmland along Left Hand Creek.

That is water leaving one drainage and being used in another. Under classic riparian rules, that alone would sink the claim.

Coffin and the other defendants farmed land on the margin of the St. Vrain, below the diversiondiversionMoving water out of the Great Lakes basin. The Compact bans new ones except in a few narrow cases., and irrigated from it naturally.

1879 was dry. There wasn’t enough water in the St. Vrain to serve both the ditch company and the downstream farms.

So the farmers went and tore out part of the company’s dam. The company sued for trespass damages and an injunction.

Did riparian rights govern in Colorado until the 1876 state constitution recognized appropriation, and can a prior appropriator carry water out of the watershed of origin?

Holding and reasoning

The court held that appropriation had governed from the earliest diversionsdiversionMoving water out of the Great Lakes basin. The Compact bans new ones except in a few narrow cases. in the territory, and that the constitution recognized an existing custom rather than creating a new rule.

Its reasoning was frankly geographic. The climate is dry, the soil is unproductive without irrigation, and water in a Colorado stream “rises, when appropriated, to the dignity of a distinct usufructuaryusufructuaryA right to use something you do not own. Your water right lets you take and use water. The water itself belongs to the public or the state. estate.” A rule requiring water to stay in its natural channel for the benefit of streamside owners who might make no use of it was, in the court’s word, “inapplicable” to Colorado.

The court also leaned on reliance. Houses had been built and thousands of acres improved on the understanding that appropriations would be protected. Deny priority and “a great part of the value of all this property is at once destroyed.”

On the watershed question the court refused to punish the company for having spent time and money to carry water over a divide. The right does not depend on where the water gets used. That single move separates water from land more completely than any other holding of the era.

Why it matters

Irwin v. Phillips (1855) said priority beats riparian on public land. Coffin went further and said riparian rights were never part of Colorado law at all. Compare 1855-irwin-v-phillips.md.

That’s why the “Colorado doctrine” is the label for pure prior appropriation, as against the California hybrid in 1886-lux-v-haggin.md.

The transbasin holding is the part with the longest shadow. Once the law says water can leave its watershed and still be yours, you get the Colorado-Big Thompson Project, you get Denver drinking from the Western Slope, and you get the entire practice of severing water from the land it came from.

What it means for a landowner today

None of this governs Wisconsin. Wisconsin never adopted appropriation, and a Wisconsin riparian owner cannot claim a dated priority.

The useful lesson is about what “owning water” means in a prior appropriation state: a decreeddecreeThe court order at the end of an adjudication, spelling out exactly who gets how much water and in what order. right, with a priority datepriority dateThe date your water right got in line. In a western drought, older dates get their full amount and newer dates get nothing. It is the single most valuable number in a western water deal., a quantity in cubic feet per secondcubic feet per secondA flow rate rather than a volume. 1 cubic foot per second running all day is about 2 acre-feet. or acre-feetacre-footEnough water to cover 1 acre a foot deep: 325,851 gallons. Roughly what 2 or 3 suburban households use in a year., a defined point of diversion, and a defined beneficial usebeneficial useActually using water for something productive: farming, drinking, industry, and in most western states now, keeping fish alive. In the West it is what earns you a water right and what caps how much you get.. Change any of those and you generally need approval, often from a water court.

If you ever evaluate western land, the questions are: what is the priority datepriority dateThe date your water right got in line. In a western drought, older dates get their full amount and newer dates get nothing. It is the single most valuable number in a western water deal., is it decreeddecreeThe court order at the end of an adjudication, spelling out exactly who gets how much water and in what order. or claimed, has it been abandoned through non-use, and where does it sit in the call?

For a Wisconsin parcel, the analogous questions are entirely different. See ../04-due-diligence/.

Subsequent history / is it still good law

Good law as of July 2026, and it remains the foundational statement of Colorado water law. Colorado now administers these rights through a water court system and a State Engineer, and interstate compactscompactA binding agreement between states that Congress approves. Once approved it becomes federal law and overrides conflicting state rules. The Great Lakes Compact is one. constrain how much Colorado can consume, but the underlying doctrine is unchanged.

The Supreme Court extended the same priority logic across state lines 40 years later in Wyoming v. Colorado, 259 U.S. 419 (1922). See 1922-wyoming-v-colorado.md.

Sources

Research demo, not legal advice. Facts current as of July 2026. Water law is state-specific and moves quickly, so confirm anything you plan to act on with a licensed attorney and the relevant state agency.