LAC 46:LXI.2913. Positional Accuracy Specification and Positional Tolerances [Formerly §2909]

A. If radial survey methods, global positioning systems (GPS) or other acceptable technologies or procedures are used to locate or establish points on the boundary survey, the professional land surveyor shall apply acceptable surveying procedures in order to assure that the allowable positional accuracy and/or positional tolerance of such points are not exceeded. Any conversion from meters to feet shall use U.S. Survey Feet. Condition | A | B | C | D Condition | Urban Business District | Urban | Suburban | Rural | Remarks and Formula Unadjusted Closure (maximum allowable) | 1:15,000 | 1:10,000 | 1:7,500 | 1:5,000 | Traverse Loop or between Control Monuments (closed traverse) Angular Closure (maximum allowable) | 10''√N | 15''√N | 25''√N | 30''√N | N = Number of Angles in Traverse (closed traverse) Accuracy of Bearing | ± 15 Sec. | ± 20 Sec. | ± 30 Sec. | ± 40 Sec. | In Relation to Source (closed traverse, radial or GPS) Linear Distances Accurate to: (maximum allowable) | 0.05 ft ± ± 0.05 ft per 1,000 ft | 0.05 ft ± ± 0.1 ft per 1,000 ft | 0.07 ft + ± 0.15 ft per 1,000 ft | 0.1 ft + ± 0.2 ft per 1,000 ft | Applies when the Distance is not part of a Closed Traverse (radial or GPS) Positional Tolerance and Positional Accuracy of any Monument (maximum) | 0.1' + AC/15,000 | 0.1' + AC/10,000 | 0.1' + AC/7,500 | 0.2' + AC/5,000 | AC = Length of Any Course* (closed traverse, radial or GPS) Calculation of area - accurate and carried to nearest ____ (decimal place) of an acre (closed traverse, radial or GPS) | 0.001 0.001 0.01 0.1 | 0.001 0.01 0.1 0.2 | 0.001 0.01 0.1 0.3 | To 1 acre To 10 acres To 100 acres To 1,000 acres Elevations for Boundaries Controlled by Tides, Contours, Rivers, etc. Accurate to: | 0.2 ft. | 0.3 ft. | 0.4 ft. | 0.5 ft. | Based on Accepted Local Datum (closed traverse, radial or GPS) Location of Improvements, Structures, Paving, etc. (Tie Measurements) | ± 0.1 ft. | ± 0.2 ft. | ± 0.5 ft. | ± 1 ft. | (closed traverse, radial or GPS) Adjusted Mathematical Closure to Survey (Minimum)** | 1:50,000 | (closed traverse, radial or GPS) *Short courses in classes "A" and "B" may generate positional errors of less than 0.01 feet. A minimum course distance of 200 feet shall be used in calculating positional error. **Smaller tracts may result in a closure less than 1:50,000. Professional land surveyor shall minimize closure constrained by precision of bearing (nearest second of angle) and distance (one hundredth of a foot).