Laserfiche WebLink
Hydrologic Soil Group — Fremont County Area, Colorado <br />Description <br />Hydrologic soil groups are based on estimates of runoff potential. Soils are <br />assigned to one of four groups according to the rate of water infiltration when the <br />soils are not protected by vegetation, are thoroughly wet, and receive precipitation <br />from long- duration storms. <br />The soils in the United States are assigned to four groups (A, B, C, and D) and <br />three dual classes (A/D, B /D, and C /D). The groups are defined as follows: <br />Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly <br />wet. These consist mainly of deep, well drained to excessively drained sands or <br />gravelly sands. These soils have a high rate of water transmission. <br />Group B. Soils having a moderate infiltration rate when thoroughly wet. These <br />consist chiefly of moderately deep or deep, moderately well drained or well drained <br />soils that have moderately fine texture to moderately coarse texture. These soils <br />have a moderate rate of water transmission. <br />Group C. Soils having a slow infiltration rate when thoroughly wet. These consist <br />chiefly of soils having a layer that impedes the downward movement of water or <br />soils of moderately fine texture or fine texture. These soils have a slow rate of water <br />transmission. <br />Group D. Soils having a very slow infiltration rate (high runoff potential) when <br />thoroughly wet. These consist chiefly of clays that have a high shrink -swell <br />potential, soils that have a high water table, soils that have a claypan or clay layer <br />at or near the surface, and soils that are shallow over nearly impervious material. <br />These soils have a very slow rate of water transmission. <br />If a soil is assigned to a dual hydrologic group (A/D, B /D, or C /D), the first letter is <br />for drained areas and the second is for undrained areas. Only the soils that in their <br />natural condition are in group D are assigned to dual classes. <br />Rating Options <br />Aggregation Method: Dominant Condition <br />Component Percent Cutoff: None Specified <br />Tie -break Rule: Lower <br />A Natural Resources Web Soil Survey 2.0 9/17/2008 <br />am— Conservation Service National Cooperative Soil Survey Page 4 of 4 <br />