3 Techniques for Checking for Land Survey Errors

Some laypeople may not know to what extent they should trust the results of land surveys. This uncertainty may be due to those people's lack of awareness about the measures that are taken to keep survey errors at a minimum level. A land surveyor carefully calculates and evaluates results along the way. This article discusses three ways land surveyors check for errors so that they give you proper survey results.

Closing the Loop

Surveyors try to ensure that they give their clients dependable results by using a technique called 'closing the loop'. This approach entails repeating the survey process from the end point back to the starting point in order to detect whether any errors were made the first time. The instruments are positioned in different locations at the points of interest. Readings are then taken and compared to establish how the results are similar or different. The comparison is based on benchmarks with elevations that are constant. Any discrepancy found is examined using other techniques in order to find an appropriate remedy.

Note Check

The surveyor then tries to find out whether the error found when closing the loop was caused by a mathematical error, such as improper addition or subtraction. Technical equations have been developed over time to help the surveyors evaluate the accuracy of the computations used during surveys. The surveyor therefore feeds the appropriate survey data into the equation and compares the outcome. The error will be attributed to a mathematical fault if the equation doesn't balance. The computation can then be repeated in order to fix the error. The mistake is likely to have originated elsewhere, such as improper instrument reading, if the equation balances despite the error discovered when closing the survey loop.

Allowable Error of Closure

It is very difficult to produce perfect survey results. This is because various factors, such as difficult terrain and equipment inaccuracies, can affect the survey outcomes. The third way to monitor errors therefore seeks to establish whether those errors are within the acceptable margin of error for the survey task that has been undertaken.

Survey authorities have standards regarding the acceptable margin of error for different survey projects. For example, the magnitude of error permitted when surveying residential lots may be much lower than the magnitude of error permitted when surveying a water body. Again, an equation is used to get the margin of error for the data gathered. Errors within the acceptable range are noted and the findings are delivered to you. Any errors that exceed the acceptable range result in repeating the survey process in order to gather more data.