Soil Map Unit Description from the RI Soil Survey Report
SwA - Swansea muck.
Link to Official Series Description for Swansea Soils
Note: These soils were formerly mapped Adrian muck in the old RI soil survey.
This nearly level, very poorly drained soil is in depressions and small drainageways of glacial till uplands and outwash plains. Most areas are oval and range from 2 to 20 acres. Slopes are dominantly less than 2 percent.
Typically the surface layer is black muck 20 inches thick. The substratum extends to a depth of 60 inches or more. It is gray fine sand to a depth of 22 inches and grayish brown gravelly sand at a depth of more than 22 inches.
Included with this soil in mapping are small areas of poorly drained Ridgebury and Raypol soils and very poorly drained Freetown, Scarboro, and Whitman soils. Also included are areas in Newport County that are underlain by loamy material. Included areas make up about 10 percent of this map unit.
The permeability of this soil is rapid. Available water capacity is high. Runoff is very slow, and water is ponded on some areas. A few areas adjacent to streams are subject to flooding. The surface layer is strongly acid through slightly acid. This soil has a high water table at or near the surface most of the year.
Most areas of this soil are in woodland or have a marsh grass and sedge plant cover.
The high water table, ponding, and the low strength of the surface layer make this soil unsuitable for community development. If the soil is drained, the organic material in the surface layer shrinks and subsides, lowering the soil surface. Slopes of excavated areas are unstable.
This soil is not suited to cultivated crops. It is limited mainly by wetness, and many areas do not have suitable drainage outlets.
This soil is suited to wetland wildlife habitat, but wetness makes the soil poorly suited to woodland wildlife habitat or open-land wildlife habitat. Capability subclass is VIw, woodland group is 5w.
Swansea soils are HYDRIC soils associated with wetlands which are protected from disturbance under state and Federal law. Any work done in or near this soil should be conducted following the proper permit procedures.