| ESI Rank | Estuarine | Lacustrine | Riverine |
|---|
| 1A | Exposed rocky shores | Exposed rocky shores | Exposed rocky banks |
| 1B | Exposed, solid man-made structures | Exposed, solid man-made structures | Exposed, solid man-made structures |
| 1C | Exposed rocky cliffs with boulder talus base | Exposed rocky cliffs with boulder talus base | Exposed rocky cliffs with boulder talus base |
| 2A | Exposed wave-cut platforms in bedrock, mud, or clay | Shelving bedrock shores | Rocky shoals, bedrock ledges |
| 2B | Exposed scarps and steep slopes in clay |  |  |
| 3A | Fine to medium-grained sand beaches |  |  |
| 3B | Scarps and steep slopes in sand | Eroding scarps in unconsolidated sediment | Exposed, eroding banks in unconsolidated sediments |
| 3C | Tundra cliffs |  |  |
| 4 | Coarse-grained sand beaches | Sand beaches | Sandy bars and gently sloping banks |
| 5 | Mixed sand and gravel beaches | Mixed sand and gravel beaches | Mixed sand and gravel bars and gently sloping banks |
| 6A | Gravel beaches
Gravel beaches (granules and pebbles)* | Gravel beaches | Gravel bars and gently sloping banks |
| 6B | Riprap
Gravel beaches (cobbles and boulders)* | Riprap | Riprap |
| 6C* | Riprap |  |  |
| 7 | Exposed tidal flats | Exposed tidal flats |  |
| 8A | Sheltered scarps in bedrock, mud, or clay
Sheltered rocky shores (impermeable)* | Sheltered scarps in bedrock, mud, or clay |  |
| 8B | Sheltered, solid man-made structures
Sheltered rocky shores (permeable)* | Sheltered, solid man-made structures | Sheltered, solid man-made structures |
| 8C | Sheltered riprap | Sheltered riprap | Sheltered riprap |
| 8D | Sheltered rocky rubble shores |  |  |
| 8E | Peat shorelines |  |  |
| 8F |  |  | Vegetated, steeply-sloping bluffs |
| 9A | Sheltered tidal flats | Sheltered sand/mud flats |  |
| 9B | Vegetated low banks | Vegetated low banks | Vegetated low banks |
| 9 | Hypersaline tidal flats |  |  |
| 10A | Salt- and brackish-water marshes |  |  |
| 10B | Freshwater marshes | Freshwater marshes | Freshwater marshes |
| 10C | Swamps | Swamps | Swamps |
| 10D | Scrub-shrub wetlands; Mangroves** | Scrub-shrub wetlands | Scrub-shrub wetlands |
| 10E | Inundated low-lying tundra |  |  |
* A category or definition that applies only in Southeast Alaska. ** In tropical climates, 10D indicates areas of dominant mangrove vegetation. |