Sentence:  The following guidelines shall be considered in determining reasonable <WSD>waterbreak</WSD> or culvert intervals: (1) On grades of 10 percent or less, intervals of 100 to 200 feet; (2) On grades of 11 to 25 percent, intervals of 75 to 150 feet; ... 
Meaning of the word marked with <WSD> tags:  A barrier built across a steeply sloping road or trail in order to direct the flow of water and prevent erosion.