For a project like this In the City of Denver, we have a crew walk the project before any demo and tie out (swing ties) any points they find. At the completion of construction they replace the point with a marker stamped "Recross" as most were chiseled crosses to begin with. The surveyor in charge deposits with the City and County a diagram showing what he found, what he replaced it with, and a statement that effectively says "I don't know what this monument represented I only perpetuated it."
I wonder if anyone has ever contacted their homeowner's insurance carrier about covering the cost of monument replacement? Less deductible of course.
Even in recording states where the fact these corner monuments exist, no one thinks to take their existence into consideration.
In California it's the law. §8771(b) of the Business and Professions Code:
When monuments exist that control the location of subdivisions, tracts, boundaries, roads, streets, or highways, or provide horizontal or vertical survey control, the monuments shall be located and referenced by or under the direction of a licensed land surveyor or licensed civil engineer legally authorized to practice land surveying prior to the time when any streets, highways, other rights-of-way, or easements are improved, constructed, reconstructed, maintained, resurfaced, or relocated, and a corner record or record of survey of the references shall be filed with the county surveyor.
Unfortunately, not all public agencies are aware of the statute, or comply with it if they are. It's a constant battle in my city; whenever I become aware of a street improvement project I contact Public Works to remind them that they need to inventory the monuments in the affected area and make perpetuation part of their construction contract. Sometimes it works, other times not so much.
The business I recently retired from and sold to my VP has laid out houses and lots for 12-15K platted lots in Central FL over the last 30 years. The ongoing problems with sidewalks in developments being skewed is because the concrete crews pull tape from the seam line of the asphalt in the road or other eyeballed gustimates if no other control is readily available. They will “pull and replace” corners also. So it’s not uncommon for them not to match.
I’ll bet if you look at the sidewalk vs. property line on the radius returns of lots 175 and 55 the sidewalk is nowhere near the property line. The only place I have seen the sidewalks and front property lines match is in plats developed prior to 1980. 😎
With just the information given you have not convinced me you have found any property corners. I agree you have found evidence but it isn't apparent they are corners. Typically the people who built the streets also built the walks and they usually are where they are supposed to be. Does your evidence fit within itself and check to a point that you are positive is an actual corner and not an offset? You may not have time to survey the entire block but you have to have enough time to survey in order to be positive you are monumenting the property correctly.