Soil Map Unit Description from the RI Soil Survey Report (2010 Update)
Sa - Sandyhook mucky peat, 0 to 3 percent slopes (2010
Update for the RI Coastal Zone Soil Survey Phase I - please download the latest
copy of the spatial data).
This nearly level, very poorly drained soil is in tidal marshes and is
subject to tidal flooding. Most areas are in salt marshes, some areas are in
brackish phragmites marshes. Slopes are
dominantly less than 3 percent.
Typically this soil has a surface layer of very dark gray mucky peat less than 8
inches thick. The underlying material is gray to black sand to a depth of 60 inches or more.
Included with this soil in mapping are a few small areas of very poorly drained
Ipswich, Pawcatuck, and Matunuck soils on similar positions. Succotash and
Fortress soils are on higher elevations, and Nagunt, Marshneck, and Massapog
soils are in permanently submersed areas. Some areas have human transported
dredge material in the surface layers. Included areas make up about 5 percent of
this map unit.
The permeability of this soil is rapid in the surface layer, rapid to very rapid
between depths of about 12 and 18 inches, and very rapid at a depth of more than
18 inches. Available water capacity is low. Runoff is very slow, and water is
ponded on some areas. The soil is strongly acid through neutral.
The daily tidal flooding and a high salt content make this soil unsuitable for
most uses except as habitat for saltwater-tolerant wildlife. Capability subclass
VIIIw; not assigned to a woodland group.
Sandyhook soils are
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.
Official Series Description:
UPDATE: The Coastal Zone of Rhode Island is currently being updated
and re-mapped, for more information on this update visit: