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 ers. It is therefore a much better ditch than the kind of ditch very often dug by erosion along the country roadside."

Where the road is built on a grade some provision should be made to prevent the wash of the gutters into great, deep gullies. This can be done by paving the bottom and sides of the gutters with brick, river rocks, or field stone. In order to make the flow in such side ditches as small as possible it is advisable to construct outlets into the adjacent fields or to lay underground pipes or tile drains with openings into the ditches at frequent intervals.

The size of side ditches should depend upon the character of the soil and the amount of water they are expected to carry. If possible they should be located three feet from the edge of the traveled roadway, so that if the latter is fourteen feet wide there will be twenty feet of clear space between ditches.

The bottom of the ditch may vary in width from three to twelve inches, or even more, as may be found necessary in order to carry the largest amount of water which is expected to flow through it at any one