Matanuska-Susitna Wetland Mapping

Cook Inlet Wetlands



A Saturday 26 June 2004 aerial photo of the eastern portion of Big Lake.

Lakes are defined as open freshwater bodies larger than 20 acres and deeper than six feet. They are not wetlands. Where lake margins support emergent or floating plants they are maped as wetlands. By definition wetlands must support plants. Pond lily (Nuphar polysepala) and other floating plants sometimes grow in water deeper than six feet. At present, 80 features have been mapped as lakes. Lakes can be supported by groundwater discharge, held perched over a confining area where precipitation exceeds evapotranspiration, or by a combination of these two factors. Groundwater discharge plays a strong role in most lakes mapped in the Greater Core Area (Jokela et. al., 1991).

Table 1. pH and specific conductance in 18 area Lakes
pH (n= 18)
Specific Conductance (25°C; n=18)
84.7 µS


pH and specific conductance measured one time only with a YSI 63 meter calibrated each sample.

Do I Need a Permit?



1987 Delineation manual

2007 Regional AK Supplement

Methods, metadata

Maps and posters

Mike Gracz
Kenai Watershed Forum 
PO Box 15301
Fritz Creek, AK  99603
13 January, 2010