I couldn't disagree with you more, John.
Working in one of the few remaining states where ownership extends "as far as the ebb shall flow" or 100 Rods, and having had a few projects requiring deteminatino of ownership below Mean High Water, I can state that the elevation observed over 18.6 years does contorl property boundaries in MA.
If I recall, the last time we "spoke" about this you referenced a MA case that I was invovled in and the court agreed with my methodology of MHW location, and it was upheld on appeal.
The high water mark changes daily, withthe tides and winds, seasons, etc...the elveation may change, and it's location on the ground may change with time, but an elevation is something that we can all place on the ground. Any other method is subjective and is arguable before any permitting boards.
Mean High Water is an established elevation, High Water Mark is an observed feature and will not control property lines in MA....
Perhaps (obviously), I should clarify... ;o)
I agree, Don, that "mean high water" is an elevation. The "mean high water line, however, is a physical feature.
So, if I'm understanding the dissension here, those who are relying upon elevations are tying their survey datum to a known benchmark, then performing a topographic survey to determine the contour elevation line locations, then staking a contour line?
I do have some hesitation understanding how the 100 Rod line is tied to an elevation. Is the 100 Rods is tied to the MHWL (a physical feature), or a contour line?
PS Storm events are a whole different ballgame as they are avulsive events. Another bag of tricks.
PSS Thanks for the slack, Rusty. Utah's Great Salt Lake does have about 10000 miles of shoreline. It's just all pointed inward instead of outward. The state has been unsuccessfully arguing "elevation" of the GSL with the Utah Supreme Court for over a century. The USC keeps pointing to the HWL that's not there either.
a line is just a line until it's given definition. MHW is an established term that has a legal definition, I assume we can agree on that? High Water Mark (as we use it around here) is the observable evidence of the last highest tide, as well as any lower tides since the last higer one.
Each of them are a "line" on the ground. MHW line, or High Water Mark line. One is by elevation the other by observation.
Your outline of the process; Topo, Determine MHW elevation, then stake a contour is correct. (By the way several towns use the flood plain contours as zoning lines for setback purposes.)
How is the 100' Rods tied to an elevation? "Ordinary low water mark " means Mean". Mass. 1909 East Boston Co v. Commonwealth 89 NE 236, 203 MA 68.17 Ann.Cas 146.....
Conversly Ordinary Mean High Water MARK means "Mean."
One of the difficulty's in using a high water mark as your boundary is that there are several to choose from at any given time. Shall you just pick the one in the middle? Without an elevation how can you figure which mark is ordinary or normal, or the Mean?
In Eastham, John, the horizontal distance between high water marks can be 20'-30' or more. The slopes on the flats are so gradual that the last high tide will leave a "wrack" line, as has each previous higher tide, wind driven, normal, still water, what ever!!! so we walk out there, do cross sections, tie in to known benchmarks and interpolate the elevation of MHW at the site. That is something that we can hang our hats on, testify to, and not have to defend the disappearing evidence that the last storm tide blew out....
Would you like a picture ?