W&M > VIMS > CCRM > Wetlands > Nontidal Wetlands > HGM Models

Nontidal Wetlands: Hydrogeomorphic (HGM) Models

Wetlands HGM Models

HGM wellsite
HGM wellsite - Photo: Dave Stanhope

This project initiated the development of HGM models in Virginia by 1) a planning exercise to identify and prioritize the needs for HGM model development in Virginia; 2) an initial effort to develop a Hardwood Mineral Flat model; 3) initial data collection on potential reference sites for other models; 4) a program to integrate remote sensing into HGM based wetland assessments; and 5) a protocol program to validate regional HGM models.


Model results for Draft Hardwood Mineral Flats.

Initiating development of a forested headwater wetland HGM model for wetlands management in Virginia.


Woody Depressional Models

Woody Depressional Area
Woody depressional area. Photo: Dave Stanhope

This project uses information developed in completion of the Development of a Forested Depressional HGM Model project and expands it to a Draft Woody Depressional Wetland HGM Model. The project expands the preliminary reference set from 8 sites to approximately 24 sites and coordinates the model development with similar efforts in Maryland and Delaware.

Draft woody depression wetland HGM model for the coastal plain of Virginia


Forested Depressional Wetland HGM

Forested Wetland
Forested wetland. Photo: Dave Stanhope

Forested depressional wetlands in the coastal plain of Virginia generally consist of topographic depressions in the landscape with soil horizon confining layers and hydrologically are predominately precipitation driven. These systems generally are considered to have no discernible surface water (channel) connections to a hydrologic source. Many coastal plain sinkhole pond complexes harbor a number of rare plants and animals and are declining throughout the region.

Initiating Development of a Forested Depressional Wetland HGM Model for the Coastal Plain of Virginia.