Map Blog #8:Isoline

This map is from the Texas Water Development Board. I see more of what is wrong with this map than what is right. First, the lines themselves are very rectangular and straightedge. I don't like the lack of curvature, but also the stroke of the line is too bold and it overwhelms the county and city boundaries. Also the number cutoffs are at strange intervals, especially in the East. The color guide is good but the shades of blue are too similar. 60 inches makes a very small section that you cannot even see. If it the intervals were grouped around 6-8 inches it would make the map flow easier.