Water Boundaries

Overview#

Water boundaries are among the most complex and contested topics in boundary law. Unlike a line defined by monuments and measured courses, a water boundary is inherently dynamic -- rivers migrate, lakes expand and contract, coastlines erode and accrete. The law must account for this dynamism while still providing certainty of ownership.

The surveyor working with water boundaries must understand not only the physical processes that shape shorelines but also the legal doctrines that determine how those changes affect property rights. A river that gradually shifts its course can transfer acres of land from one owner to another. A sudden flood that cuts a new channel may have no effect on ownership at all. The distinction between gradual and sudden change -- between accretion and avulsion -- is fundamental to water boundary law.

"Shorelines are dynamic in nature, and their locations may change considerably with time." -- Robillard & Wilson, Evidence and Procedures for Boundary Location (6th Ed.), Ch. 8, Sec. 8-15

This article covers the legal framework governing boundaries along rivers, streams, lakes, and oceans, including the rights of adjacent landowners and the effect of natural and artificial changes on boundary location.

Riparian and Littoral Rights#

Definitions

The law distinguishes between two types of water-adjacent ownership based on the type of water body:

In common usage, "riparian" is often used loosely to refer to both types of waterfront ownership. In legal and surveying contexts, the distinction matters because different rules may apply to flowing water (which has a current and a channel) versus standing or tidal water (which does not).

The Bundle of Riparian Rights

Riparian and littoral ownership carries a bundle of rights that extend beyond the upland boundary to the water itself:

1. Right of access to the water from the upland property
2. Right to use the water for reasonable domestic and agricultural purposes
3. Right to wharf out -- to build docks, piers, and wharves into the water
4. Right to accretions -- to gain title to land gradually added by water action
5. Right to an unobstructed view of the water (in some jurisdictions)
6. Right to the flow -- the water must continue to flow in its natural quantity and quality (in riparian rights jurisdictions)

"With respect to the ownership of lands adjoining tidewaters, lakes, or rivers, riparian rights attach to the land." -- Robillard & Wilson, Brown's Boundary Control and Legal Principles (7th Ed.), Ch. 1, Sec. 1.12

These rights are incident to the ownership of waterfront land. They cannot ordinarily be separated from the upland parcel and sold independently (except by specific grant of an easement or profit).

The Ordinary High Water Mark#

The boundary between public and private ownership along navigable waterways is typically defined by the ordinary high water mark (OHWM). This is the physical line on the shore that separates public waters (owned by the state for the benefit of the public) from private upland.

Determining the OHWM

The ordinary high water mark is not a single, easily identifiable line. It is a zone where the water's influence transitions from permanent to intermittent. Various indicators are used to locate it:

In tidal areas, the boundary is often defined as the mean high water line (MHW) -- the average of all high tides over a 19-year tidal epoch (the National Tidal Datum Epoch). Some states use the mean higher high water line (MHHW) or the mean high tide line.

Public Trust Doctrine

Below the ordinary high water mark (or mean high water in tidal areas), the bed and banks of navigable waterways are generally held by the state in trust for the public. This is the public trust doctrine, derived from English common law. The state holds these submerged lands for the purposes of navigation, commerce, and fishing.

The boundary between the public trust and private ownership is therefore the OHWM or MHW line -- and because this line moves with the water, it is an ambulatory boundary.

Navigable vs. Non-Navigable Waters#

The navigability of a waterway is a threshold legal determination that affects ownership of the bed and the rules governing the water boundary.

Federal Test for Navigability

Under the federal test (established in The Daniel Ball, 77 U.S. 557, 1870), a waterway is navigable if it is "used, or is susceptible of being used, in its ordinary condition, as a highway for commerce." This includes waterways that can carry boats or rafts for commercial purposes, even seasonally.

Ownership of the Bed

For non-navigable streams, when a deed calls "to the stream" or "along the creek," the boundary extends to the center of the stream, giving the riparian owner title to the bed to the midpoint.

The Thread of the Stream Doctrine#

When a non-navigable stream forms the boundary between two parcels, the boundary typically runs along the thread of the stream -- the centerline of the watercourse. However, courts are divided on what "center" means:

"The term 'thread of the stream' means the geographic center of the stream at ordinary or medium stage of the water, disregarding slight and exceptional irregularities in the banks. It is fixed without regard to the main channel of the stream." -- Robillard & Wilson, Evidence and Procedures for Boundary Location (6th Ed.), Ch. 8, Sec. 8-14

An alternative view holds that the thread is the thalweg -- the line following the deepest part of the channel. This approach gives both riparian owners access to the water even at its lowest stage.

The applicable standard depends on the jurisdiction. For navigable streams where the state owns the bed, the thalweg is often used as the state-private boundary on streams forming state borders (as between states in interstate disputes).

Accretion#

Accretion is the gradual and imperceptible addition of land to a riparian or littoral parcel through the action of water. Soil, sand, and other material deposited by the current or waves build up along the shore, extending the landowner's property outward.

The key characteristic of accretion is its gradual nature. The addition must be so slow that it cannot be observed as it happens -- it is noticed only in retrospect. The law awards accreted land to the adjacent upland owner because:

1. The boundary is defined by the water's edge, and the edge has moved
2. The upland owner bears the risk of erosion, so they receive the benefit of accretion
3. Separating accreted land from the upland would create impractical strips of land without access

"A person may lose land by erosion or gain land by reliction or accretion. The initial right to follow receding or encroaching waters is defined or implied by a written conveyance, but the actual land area of a person's holdings is increased or decreased without a change in the writings." -- Robillard & Wilson, Evidence and Procedures for Boundary Location (6th Ed.), Ch. 13, Sec. 13-2

Apportionment of Accretions

When accretion adds land to a stretch of shore shared by multiple owners, the new land must be divided among them. The general rule is that accretions are apportioned in proportion to each owner's frontage on the water body. The BLM Manual of Surveying Instructions provides detailed guidance on apportioning accretions in the context of public land surveys.

Reliction#

Reliction (also called dereliction) is the gradual recession of water, exposing land that was formerly submerged. Like accretion, reliction must be gradual and imperceptible to benefit the adjoining landowner.

Reliction differs from accretion in its mechanism: accretion involves the deposit of new material, while reliction involves the withdrawal of water. The legal effect is the same -- the exposed land belongs to the adjacent upland owner.

Common causes of reliction include:

• Natural lowering of a lake or reservoir level
• Long-term drought reducing stream flow
• Changes in watershed hydrology

If the recession is sudden (caused by an earthquake, dam failure, or human intervention), it is treated as avulsion, not reliction, and the boundary does not move.

Avulsion#

Avulsion is a sudden and perceptible change in a watercourse or shoreline. Unlike accretion and reliction, which are gradual, avulsion involves a rapid, observable alteration -- a flood that cuts a new channel, a storm that deposits a mass of earth, or a river that breaks through a meander and takes a new course.

The critical legal distinction is this: avulsion does not change the boundary. When a river suddenly shifts its course, the boundary remains where the river was before the avulsive event. The rationale is that the law should not reward sudden, catastrophic changes with the transfer of large tracts of land.

"In general, water boundaries change with shoreline changes. However, sudden changes due to avulsive activities generally do not result in a boundary shift." -- Robillard & Wilson, Evidence and Procedures for Boundary Location (6th Ed.), Ch. 8, Sec. 8-15

Comparison Table

The Ambulatory Nature of Water Boundaries#

A water boundary is ambulatory -- it moves with the water. This is one of the most fundamental characteristics distinguishing water boundaries from boundaries defined by fixed monuments. As the shoreline migrates through accretion, erosion, or reliction, the property boundary migrates with it (subject to the avulsion exception).

This ambulatory character means that a survey of a water boundary is valid only for the date of the survey. The shoreline position last year, last decade, or at the time of the original grant may be different from today's position. The surveyor must determine the current location of the water line and apply the appropriate legal standard (OHWM, MHW, thread of the stream) at the time of the survey.

Meander Lines vs. Water Boundaries#

In the PLSS, surveyors ran meander lines along the banks of navigable waterways and large lakes. These meander lines are sometimes mistakenly treated as boundary lines. They are not.

Meander lines were run for the purpose of computing the area of lots or sections adjacent to water. They represent an approximation of the shore position at the time of the survey, used for area calculation and cartographic purposes.

"In no case is the meander line intended to be a boundary line." -- Robillard & Wilson, Evidence and Procedures for Boundary Location (6th Ed.), Ch. 9

The actual boundary of a riparian lot is the water itself -- specifically, the ordinary high water mark or the thread of the stream, depending on the type of water body and its navigability. The meander line may be evidence of where the water was at the time of the survey, but it is not the boundary.

The exception arises when a body of water depicted on the government plat never actually existed, or was misrepresented. In such cases, some courts have held the meander line to be the boundary, since there is no water body for the boundary to follow.

The Effect of Artificial Changes#

When human activity causes a shoreline change -- dredging, filling, construction of jetties, dam construction -- the legal treatment depends on who caused the change and whether it was gradual or sudden.

General Rules

1. A riparian owner may not benefit from artificial accretion caused by their own actions. If a landowner builds a groin or jetty that causes sand to accumulate on their property, they do not acquire title to the accreted land.

2. Artificial changes caused by third parties or the government may or may not affect the boundary, depending on the jurisdiction and the circumstances.

3. Dam-created changes present special problems. If a dam raises a lake level, submerging previously dry land, the submerged land may still belong to the upland owner (depending on the dam operator's legal authority). If the dam is removed and the water recedes, the exposed land generally returns to the original owner.

"In most states, a riparian owner may not benefit from shifts due to artificially caused accretion or avulsion resulting from his or her actions. Therefore, a knowledge of the cause of the shoreline change is desirable for a correct interpretation of the boundary location." -- Robillard & Wilson, Evidence and Procedures for Boundary Location (6th Ed.), Ch. 8, Sec. 8-15

Practical Surveying of Water Boundaries#

Surveying a water boundary requires different techniques and considerations than a conventional metes and bounds survey:

1. Determine the applicable legal standard. Is the boundary the OHWM, MHW, thread of the stream, or thalweg? This depends on the type of water body, its navigability, and the jurisdiction.

2. Locate the physical indicator. Use vegetation, soil, debris, bank escarpment, and hydrological data to establish the water line.

3. Date the survey. Because water boundaries are ambulatory, the survey is valid only for its date. Note the date prominently on all deliverables.

4. Investigate the cause of changes. If the shoreline has moved since the original survey, determine whether the change was gradual (accretion/reliction) or sudden (avulsion). This determines whether the boundary moved with the water.

5. Research historical shoreline positions. Aerial photographs, historical maps, and prior surveys can establish the rate and direction of shoreline change.

6. Document thoroughly. Water boundary surveys should include photographs, vegetation mapping, soil sampling results, and reference to hydrological records.

Key Takeaways#

• Riparian rights attach to land adjacent to flowing water (rivers, streams); littoral rights attach to land adjacent to standing or tidal water (lakes, oceans).
• The ordinary high water mark (OHWM) is the typical boundary between public and private ownership along navigable waterways.
• Accretion (gradual addition of land) and reliction (gradual recession of water) move the boundary with the water, benefiting the upland owner.
• Avulsion (sudden change) does not move the boundary -- ownership remains as it was before the sudden event.
• Water boundaries are ambulatory -- they move with the water over time, making surveys date-specific.
• Meander lines are not boundaries. They were run for area computation. The actual boundary is the water itself.
• Artificial changes generally do not benefit the party who caused them.
• The thread of the stream (center or thalweg) is the boundary of non-navigable streams when the deed calls "to the stream."
• The navigability of a waterway determines who owns the bed and what legal standards apply to the boundary.

References#

1. Robillard, W.G. & Wilson, D.A. Brown's Boundary Control and Legal Principles (7th Ed.). John Wiley & Sons, 2014. Chapter 9.
2. Robillard, W.G. & Wilson, D.A. Evidence and Procedures for Boundary Location (6th Ed.). John Wiley & Sons, 2011. Chapter 8.
3. Cole, G.M. Water Boundaries. John Wiley & Sons, 1997.
4. U.S. Department of the Interior, Bureau of Land Management. Manual of Surveying Instructions (2009). Sections on meander lines and riparian boundaries.
5. The Daniel Ball, 77 U.S. 557 (1870) (federal navigability test).
6. Nebraska v. Iowa, 143 U.S. 359 (1892) (accretion and avulsion in interstate boundary disputes).
7. County of St. Clair v. Lovingston, 90 U.S. 46 (1874) (riparian owner's right to accretions).