In my last column, we discussed riparian boundary lines, riparian rights, and set up the general parameters for riparian boundary location in the tidelands where, generally speaking, ownership of the submerged lands will be vested in the sovereign, and the uplands will belong to the riparian owner. We recognized that the commencement of the riparian rights will be at the mean high tide line and will extend out into the tidelands until they terminate where the riparian rights meet the paramount interests of the state and federal government relative to navigation. These are simple concepts that may present some technical difficulties. Nevertheless, the reasonably competent surveyor should be able to determine where these beginning and ending points are located.

The more difficult task will be determining the lateral limits of the riparian rights. In other words, the seaward projection of the riparian boundary lines when the shoreline and existing structures in the tidelands will not conform to the theoretically correct apportionment of the available riparian-use areas. The virgin coastline where theory can be put into practice is quickly evaporating, and conflict and litigation are taking its place. All landowners want what is theirs and riparian owners are no different in this regard. However, riparian rights are not the same as upland property rights, and this is one of the keys to understanding the problem and how to resolve the lateral location question.

Principles of Riparian Boundary Location

In this column, we will look at a scenario where the shoreline is crowded and the common theories of apportionment are not workable. A scenario where surveyors and other consultants hired by the riparian owners put forward unworkable theoretical solutions because there are no established guidelines for such situations and/or the permitting regulations have no answer because they are based on the available theories of apportionment. 

To recap, the principles for riparian boundary location that we developed last time (December 2019), are as follows:

  1. Riparian rights are not absolute rights; 
  2. Existing improvements in the tidelands were permitted; 
  3. Existing improvements in the tidelands are monuments that memorialize a previous riparian boundary determination; 
  4. Even if not previously permitted, existing improvements that are at least 20 years old (period of repose) were approved by the acquiescence and acceptance of the adjoining landowners and other boundary establishment doctrines may apply; 
  5. Equitable principles apply to the distribution of now available riparian-use areas in the tidelands; and 
  6. Equitable principles also apply to the enforcement of regulatory requirements for the installation of new improvements in a highly improved shoreline environment.

Another key understanding is that in order to apply these principles the surveyor must be more like a judge sitting in equity, than a partisan employee or advocate for the client. To be helpful, as opposed to causing more confusion and even litigation, the surveyor must be able to gather, weigh and evaluate the best of the available evidence that the reasonably prudent practitioner would in like or similar circumstances, and render a well-reasoned opinion on the most probable location of the riparian boundaries. 

Anybody can throw up an unworkable theoretical location that has no possibility of success, short of removal of existing structures or a court order. The surveyor has no power to do either of these things. What the surveyor can do is render an equitable, common-sense and well-reasoned opinion on the location question. The client can choose to accept that opinion and move on, or end up in a fight costing tens if not hundreds of thousands of dollars. Should the well-reasoned opinion ultimately turn out to be correct, then in retrospect, it will be seen that the surveyor was the hero as opposed to the zero, as is too often the case.

Example Scenario


riparian boundaries figure 1
Figure 1

Our example scenario involves the last owner to come to the party. It is a small lot with no improvements surrounded by a highly developed shoreline. The lot gets sold to a new owner who, of course, wants to exercise her riparian rights by having a new pier and a 30’x30’ boat dock built to allow for deep-water access. The first consultant hired wants to please the client and proposes the theory of “deep-water apportionment,” to get the client directly in contact with deep water. (See Fig. 1) Short of a lawsuit this plan is a fantasy and is not approved for a permit by the applicable Department. 


The client fires the first consultant and hires another one. The second consultant realizes that the deep-water apportionment theory was rejected, so this consultant postulates that the property is in a cove and utilizes the “cove apportionment" theory. As the theory dictates, the curve of the cove is smoothed, and the riparian boundaries are projected perpendicular to the tangent. The convergence of the lines and the associated riparian rights terminate well before deep water and create an encroachment into the boat dock of the adjoiner to the east. (See Fig. 1) The client is appalled and fires the consultant without proposing the plan to the Department. This does, however, suggest that a previous cove determination may have been made when the riparian boundary of the adjoiner to the east was originally established.  


riparian boundaries figure 2
Figure 2

A third consultant assumes the straight-shoreline “perpendicular apportionment” theory in order to put the proposed boat dock as close to the deep water as possible. This plan projects the riparian boundaries out into the tidelands perpendicular to the shoreline. (See Fig. 2) This approach has the proposed pier scooting around the west side of the eastern adjoiner’s existing boat dock and places the proposed boat dock directly in front of the same. The plan effectively cuts off the existing riparian boundaries of at least the next three owners to the east. This plan is also rejected, and the client is starting to bleed money on surveying, consultants and plan preparation.



riparian boundaries figure 3
Figure 3

The fourth consultant recognizes that the Department’s permitting regulations require a 10-foot offset along any approved riparian boundary line. This consultant determines that the eastern riparian boundary should run along the western edge of the existing boat dock to the east and the proposed boat dock will be placed 10 feet to the west. The western riparian boundary is then run 10 feet west of the eastern edge of the new proposed boat dock as required by the regulations. These lines, however, indicate that the client’s riparian rights terminate at the boat dock of the adjoiner to the west before reaching deep water. (See Fig. 3) 


The adjoiner to the west finds out about this plan and starts writing letters to the Department opposing the plan. If the Department approves this plan, the neighbor to the west is going to file a lawsuit. The client isn’t happy because she’s not getting what she wants but doesn’t want to spend the money defending a lawsuit on top of building a boat dock. The Department doesn’t like it because it doesn’t fit its formula and also because of the trouble it will bring. So far, however, this is the only plan that takes into consideration existing conditions in the tidelands. All parties want a different solution. 

Application of the Principles

Having effectively eliminated theoretical resolutions of the problem and four previous plans, we will turn to our formulated principles. The first principle is that the riparian rights are not absolute. Should the determination be that the riparian rights terminate short of deep water, this is of no import because this will not prevent the client from actually reaching deep water. None of the adjoiners will be able to block such passage with a structure without a permit, it just means that the client may not be able to have a boat of the desired size due to the depth of the water. 


riparian boundaries figure 4
Figure 4

The second, third, and fourth principles dictate that the existing structures were permitted and that, according to existing regulations, a 10-foot offset to these structures was employed. In other words, the riparian boundaries have already been run and now the task is to retrace them. Using the existing structures as monuments memorializing the previous determination of the riparian boundaries, we can apply a 10-foot offset to the existing structures on both sides, resulting in riparian boundaries as indicated on Fig. 4. It is worth noting that the western riparian boundary thus determined comes close to a theoretical cove location as might have been determined in the past. See “Possible Cove Line” on Fig. 4. 


With a waiver of the setback requirement on your client’s side of the lines, a 30’x30’ boat dock can be placed along-side the neighbor’s boat dock to the east with no encroachment into either neighbor’s existing riparian boundaries. A waiver would be equitable, but beyond the surveyor’s control. Nevertheless, this result would be an equitable distribution of the remaining riparian-use area. The client might not be happy, but short of a lawsuit and more wasted money, your client is the last one to the party and equity dictates “first in time, first in right.” 

What about the neighbor to the west? There has been no violation of his existing riparian boundaries and, except for the waiver, he has nothing to complain about. Besides, just look at his monstrous boat dock that is causing the buildup of submerged soils on all sides. Equity also dictates that “those who want equity must do equity” and the equitable doctrine of “clean hands” is implicated. 

What about the neighbor to the east? Well, when you were out there doing your survey work you struck up a conversation with him and his suggestion was that your client “just build it right next to mine, and everybody will be happy.” This is parol evidence that supports the determination.

In essence, the determination of riparian boundaries in a highly developed shoreline environment is a retracement survey based upon evaluation of existing conditions, monuments memorializing the location of previous determinations, and includes evaluation of available parol evidence. When shorelines have moved over time, parol evidence may be essential and can be conclusive. Theoretical locations, as in all boundary determinations, may be helpful in evaluating evidence but that’s about it, and should never overcome common sense. 

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  1. Due to space limitations, a complete summary of the common apportionment theories for the distribution of riparian rights in sovereign tidelands is impossible. In 1985 and again in 2009, the Florida Department of Environmental Protection, Division of Lands, Bureau of Survey and Mapping, sponsored a study entitled, “Guidelines for Allocation of Riparian Rights,” by the late Dr. David Gibson, of the University of Florida. A copy of that document can be downloaded at:  
  2. Any resemblance to real-life conditions in our example are purely coincidental and are not intended to represent any actual persons, places or circumstances.

Neither the author nor POB intend this column to be a source of legal advice for surveyors or their clients. The law changes and differs in important respects for different jurisdictions. If you have a specific legal problem, the best source of advice is an attorney admitted to the bar in your jurisdiction.