detail about reduecd level?
pink
Invert Level is the bottom of the pipe, reduced level is the middle of the pipe.
A reduced level is the vertical distance between a survey point and the adopted level datum
Black
apathy
In surveying, the invert level refers to the elevation of the bottom of a drainage or sewer pipe, indicating the lowest point where water can flow. In contrast, the reduced level (RL) is a reference elevation used to simplify measurements, typically expressed relative to a benchmark or datum point. While the invert level is specific to drainage systems, the reduced level can apply to various points on a site for overall topographical analysis. Both are crucial for ensuring proper drainage and site grading.
metres above the mean sea level
The color red is used to indicate the level on a SITREP report that defines an area that has been reduced in strength. Green and amber indicate levels that are performing at or above expected strength.
A reduced level is the vertical distance between a survey point and the adopted level datum. There are two methods for calculating reduced levels, namely the "rise and fall" method and the "height of collimation" method. The latter reduces levels relative to the instrument height. As it has inferior built-in checks, it is unreliable.
height of reference point to determine level
Reduced Level
38.4 inches