Wetland Classification and Mapping of Seward, Alaska



Map Unit Descriptions


Ecosystem: Riparian


Map Component: RD4F1; RD4F1c


Seward Area Extent: 4 wetland polygons; 25.0 acres

The open water in the large wetland complex adjacent to Nash Road is fed by springs, and probably by both flooding and hyporheic water from the Resurrection River and Salmon Creek.

Wetland Indicators

Type: Open water, a water of the US, but not a wetland.

Average depth to water table: above the surface

Average organic layer thickness: 19 cm

Average depth to redoximorphic features: 0 cm

Common Soils: Typic or Histic Cryaquepts at margins

Common Plant communities:

Water horsetail (Equisetum fluviatle)



HGM: Bidirectional, non-tidal Floodplain flat

RD4F1 wetlands support standing water in the floodplain of a glacier-fed braided stream valley.  Four of these wetlands are mapped in the Seward area, two adjacent to the Resurrection River system, and two adjacent to the Snow River system.  The two in the Resurrection system are fed primarily by groundwater originating on the large rock drumlin to the north.  They are largely cut-off from the river by both Nash Road, and recent flooding.  A Resurrection River channel is shown flowing through the wetland complex the two RD4F1 wetlands are located in, on 1:25,000 USGS topographic maps.  Field visits indicate that recent deposition between the current river channel and the wetlands has resulted in some isolation.  The next flood could either increase that deposit, further isolating the wetlands, or cause the channel to re-occupy its former position.

One of the two RD4F1 wetlands adjacent to the Snow River is maintained by an extensive beaver dam.  The other may be partially impounded by a river access road.

RD4F1c refers to a created floodplain pond ("Roundhouse Pond' near the coal loading facility, and a small pond between the airport and the three bridges).


Floodplain regulation

From The Kenai Borough website:

"The Kenai Peninsula Borough manages a Floodplain Ordinance that addresses proper development to reduce flood risks and lessen the economic losses caused by flood events. The ordinance provides building standards for construction projects within the floodplain to ensure the availability of flood insurance through the National Flood Insurance Program. These building requirements also are intended to minimize or prevent damage when flood events occur. The ordinance requires floodplain development permits for all projects in floodplains."


Do I Need a Permit?

 Introduction and Key to Plant Communities  

Introduction and Key to Ecosystems

    Kenai Hydric Soils    Map Unit Summary    Methods    Glossary



Contact: Mike Gracz
Kenai Watershed Forum 
Homer Field Office
Old Town Professional Center
3430 Main Street Suite B1
Homer, AK  99603

12 February 2007 15:24