XSCircularPreprocessedGetNaturalDepthBase Method

Same results as GetNaturalDepth(Double, Double), when manning is uniform (no depth dependence). Otherwise results will differ slightly. This version is more "correct", since calculate the max conveyance based on MAR23 and limits the value of MAR23, while the GetNaturalDepth(Double, Double) does it only on AR23. Hence results will differ when manning varies with depth. However, with the _relativeAR23 table it is possible to do binary search (currently linear search)

public double GetNaturalDepthBase(
	double discharge,
	double slope
)