Surface water diversion in Texas — strict liability under Water Code § 11.086

Development changes where rain goes. A pad site is graded, a driveway is poured, a berm goes in, and water that used to spread across a field now runs onto the property next door.

Texas answers that with a statute rather than a tort. Water Code § 11.086(a): "No person may divert or impound the natural flow of surface waters in this state, or permit a diversion or impounding by him to continue, in a manner that damages the property of another by the overflow of the water diverted or impounded."

No negligence is required. Whether the defendant was careful is not an element.

What the claim is

Someone altered the land and the water that used to go elsewhere now floods yours.

Where the right comes from

Water Code § 11.086. Subsection (b) supplies the remedy: "A person whose property is injured by an overflow of water caused by an unlawful diversion or impounding has remedies at law and in equity and may recover damages occasioned by the overflow."

What a plaintiff has to prove

1. The defendant diverted or impounded the natural flow of surface water, or permitted a diversion or impounding of theirs to continue;
2. In a manner that damaged the plaintiff's property; and
3. By the overflow of the water diverted or impounded.

Nothing about intent. Nothing about care. A defendant who hired a competent contractor, pulled every permit and built to plan is liable if the work diverted the water and the water did the damage.

Surface water — the definition that decides the case

This is where these claims are won and lost, and the rule is narrow.

Surface water is diffused water — rain and snowmelt spread over the ground, following no defined course, before it reaches a channel. It has no banks, no bed, no permanent source.

Once water enters a natural watercourse it stops being surface water, and § 11.086 stops applying. A creek, a bayou, a slough, a gully with a defined bed and banks — water in any of those is watercourse water, and the statute does not govern it.

So the same flood produces opposite answers depending on where the water came from. Runoff pushed across a property line by a neighbour's new grading is a § 11.086 claim. A creek that jumped its banks after a storm is not, and the plaintiff is back to negligence, nuisance or, against a government defendant, inverse condemnation.

What the statute does not reach

Section 11.086(c) exempts the construction and maintenance of levees and other flood-control improvements in rivers, creeks and streams, and the construction of canals for irrigation or other purposes the Water Code authorises. That exemption has its own limit: it does not authorise a canal, lateral canal or ditch that obstructs a river, creek, bayou, gully, slough, ditch or other well-defined natural drainage.

Section 11.086(d) permits an owner whose land floods because gullies or sloughs have cut into the banks of a river or creek to fill the mouths of those gullies or sloughs up to the height of the adjoining banks, without liability to other property owners.

How long you have to file

Two years under CPRC § 16.003(a), which covers trespass for injury to the property of another.

Accrual depends on whether the injury is temporary or permanent, and the distinction matters more here than in almost any other property claim.

A temporary injury — flooding that recurs sporadically, depending on rainfall, and can be abated — gives a new cause of action with each flood. The plaintiff recovers for the damage from floods within the limitations window, and the claim does not expire while the condition remains.

A permanent injury — a condition that is constant and will continue indefinitely — accrues once, when the injury first becomes apparent, and the plaintiff recovers the whole loss in market value then. A landowner who waits through five years of flooding on the assumption that each event starts a new clock can find the claim characterised as permanent and time-barred.

What has to happen before you file

Nothing. Documentation is the practical requirement: photographs before and after the work, the elevation certificates, the drainage plans filed with the city, and dated records of each flood.

What the claim pays

Damages for the injury to the property. For a temporary injury, the cost of repair and the loss of use for each flood. For a permanent injury, the loss in the market value of the land.

Damage to personal property — the contents of the house, the equipment, the crops, the livestock.

Injunctive relief, and this is often the point. Section 11.086(b) gives remedies "at law and in equity," which supports an order requiring the defendant to remove the berm, regrade the site, or restore the drainage.

Exemplary damages, where the diversion was intentional or grossly negligent, on clear and convincing proof under CPRC § 41.003.

No attorney's fees. Section 11.086 provides none, and neither does CPRC § 38.001 for a property tort. Where a declaratory judgment is also sought, CPRC § 37.009 permits a discretionary award.

Who can be sued

The neighbouring landowner who did the work.

The developer or builder who graded the site — and the statute reaches whoever "permits a diversion or impounding by him to continue," which keeps a current owner liable for a predecessor's berm they have left in place.

A municipality or district, subject to governmental immunity. A claim that a city's drainage project deliberately redirected water onto private land is generally pleaded as inverse condemnation under article I, § 17 of the Texas Constitution, which requires an intentional act and avoids the Tort Claims Act's notice deadline and caps.

Common defenses

• The water was not surface water — it was in a natural watercourse. The leading defence, and often decisive.
• No diversion — the flow was unchanged, and the flooding came from rainfall volume.
• The § 11.086(c) exemption for authorised flood-control or irrigation works.
• The § 11.086(d) allowance for filling gullies and sloughs.
• No causation — the damage came from a storm that would have flooded the property anyway.
• Limitations, on a permanent-injury theory.
• Governmental immunity, for a public defendant.

What people get wrong

Fault is not an element. The defendant's care, permits and professional advice are irrelevant to liability under § 11.086.

A creek overflowing is not this claim. Water in a watercourse is outside the statute.

An injunction may be worth more than damages. Repairing the flood damage does nothing about the next storm. Section 11.086(b) supports an order to remove the diversion.

Buying the property does not clear the problem. A current owner who permits an existing diversion to continue is within the statute's terms.

Fees are not recoverable. Which shapes the economics, and is why these cases are often pleaded with a declaratory judgment count.

Where it came from

Two doctrines compete in the law of surface water. The common enemy rule lets every landowner fend off water however they like, and the civil law rule requires the lower estate to receive the natural drainage of the upper and forbids either owner to alter it.

Texas took the civil law rule and put it in a statute — first in 1915, and in its present form since

1. The choice suits a state where flat terrain, heavy rainfall and rapid development combine to

make drainage a constant source of dispute, and where a single graded pad can move a great deal of water a short distance onto someone else's land.

The strict liability standard is what makes the statute work. Proving negligence in a drainage case would mean litigating engineering judgment, permit compliance and industry practice in every suit. Section 11.086 asks a simpler question — did the defendant's work divert the water, and did the water do the damage — and leaves the argument where the facts are.

Common questions

My neighbour's new driveway floods my yard. Can I sue?

Yes, if the work diverted or impounded the natural flow of surface water and the overflow damaged your property. You do not have to prove your neighbour was careless.

Do I have to prove negligence?

No. Water Code § 11.086 imposes strict liability.

What if the flooding came from a creek?

Then § 11.086 does not apply. Once water is in a natural watercourse it is no longer surface water, and the claim has to be pleaded as negligence, nuisance, or inverse condemnation against a government defendant.

How long do I have to sue?

Two years. For recurring temporary flooding, each event can start a new period; for a permanent condition, the period runs from when the injury first became apparent.

Can I make them undo the work?

Yes. The statute provides remedies at law and in equity, and an injunction requiring removal or regrading is available.

Can I recover attorney's fees?

No, unless a declaratory judgment count supports a discretionary award.

Where these rules live

• CPRC § 16.003 — Two-year limitations period
• CPRC § 41.003 — Standards for recovery of exemplary damages
• CPRC § 37.004 — Subject matter of a declaratory judgment
• CPRC § 37.009 — Costs and attorney's fees on a declaratory judgment
• CPRC § 65.011 — Grounds for an injunction
• CPRC § 16.026 — Adverse possession: ten-year period