Laserfiche WebLink
In which, <br />L~1 length of lateral berm spillway <br />H height between top of berm and spillway crest <br />2.6 BERM TOP WIDTHS - RIVERBANK BERMS <br />This section specifies the minimum top width for gravel mine berms <br />located adjacent to the South Platte River. The top width require- <br />ments are specified to protect the berms from rapid failure during <br />floods. Such failure may result in the South Platte River flowing <br />through the adjacent gravel pits and subsequently damaging property <br />along the river. The berm top width requirements consider long term <br />stability and safety along the South Platte River. Localized damages <br />to the berms may result during large floods and may require periodic <br />repair and maintenance as determined by the Adams County Engineer. <br />The top widths are broken into two. classifications, one for an unpro- <br />tected river bank and one for protected river banks. Unless otherwise <br />indicated, the requirements of Sections 2.3 - Riverbank Protection and <br />2.4 - Pitside Bank Protection constitute adequate bank protection. <br />The top widths are expressed as the distance between the top of the <br />river bank slope to the top of the pitside slope. The area between <br />these two tops of slopes should be no steeper than 3 percent and as a <br />minimian have a stand of vegetation which reasonably closely resembles <br />the native vegetation along the site. <br />2.6.1 Existing Unstable Alignment <br />When the river is allowed to maintain its existing unstable <br />alignment, and no bank protection is provided beyond the nec- <br />UDSFCD GRAVEL GUIDELINES 12/17/87 <br />2-28 <br />