swales

by Lynn

I have a homework assignment and I could use some help. Here it goes:
A tennis court and walkway going to it is sited on a hill. Existing contours go from 86 at bottom of page to 94 at top of page and cross tennis court diagonally. Tennis court has a 1% grade. I was able to find the elevations of the court Where the walk meets the court is at 91.4. Teacher said to arbitrarily locate a H.P. on the walk and locate it. He also said to try a 2% slope on walk. So we located 91.2 on the walk at 10' away from the tennis court. The he said to locate the whole # contours on the walk. So between 91.4 and 91.2 there aren't any whole contours and yet he has begun his swales at 91. I also don't understand how he pulled the contours.
Can you help?

ANSWER
It's a little difficult to give you an exact answer without seeing the diagram. However, if the contours are running diagonally, you have to continue/extend them along the land so that they cross the walkway, Just because there is no whole contour between 91.2 and 91.4, does not mean that whole contours do not pass the walkway further away.

I would assume that 91 crosses over the walk at some point (further away from the tennis court). In addition, if you extended the walkway and made it long, 92 would cross it over.

You did not mention how the slope is running (right to left or left to right) or which side the walkway is on, so things may be a little different with a different configuration. The point is, is that whole contours will pass through the walk at some points.

Your swale could be running along the edge of the tennis court, but 91.4 is just the number between 91 and 92 which might make up the contours of the swale. Your swale might also be further away on the walk with the tennis court water and adjacent walkway water draining towards it.

I think.

Susan