Alaska Peninsula - Iliamna and Bristol Bay Lowlands Area, Alaska

Survey Area AK715 Alaska

The dominant drainage class is Well drained and the dominant hydrologic group is B (moderate infiltration). This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in Alaska Peninsula - Iliamna and Bristol Bay Lowlands Area, Alaska.

Soil Map UnitAcresDrainageHydro GroupDwellingsSeptic
Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Upland-Glaciated Plains, Ash Influenced 1.3M Very poorly drainedBVery limitedVery limited
Bristol Bay-Northern Alaska Peninsula Lowlands-Boreal and Northwest Maritimel-Glaciated Plains, Ash Influenced 1.2M Well drainedANot limitedVery limited
Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Water, Fresh 599K Not limitedNot limited
Southern Alaska Peninsula Mountains-Maritime Upland-Rounded Mountains 549K Well drainedBVery limitedVery limited
Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Upland-Glaciated Plains and Peatlands 378K Very poorly drainedB/DVery limitedVery limited
Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Water, Saline 295K Not limitedNot limited
Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Lowlands-Coastal Plains, Low 213K Very poorly drainedB/DVery limitedVery limited
Southern Alaska Peninsula Mountains-Maritime Water, Saline 208K Not ratedNot rated
Southern Alaska Peninsula Mountains-Maritime Upland-Glaciated Plains and Hills 198K Well drainedBVery limitedVery limited
Southern Alaska Peninsula Mountains-Maritime Alpine-Barren Mountains 96K Very limitedVery limited
Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Upland-Glaciated Plains and Hills 92K Very poorly drainedB/DVery limitedVery limited
Cook Inlet Lowlands-Boreal Water, Saline 85K Very limitedVery limited
Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Upland and Lowland-Glaciated Valleys 83K Well drainedBVery limitedVery limited
Cook Inlet Mountains-Boreal Upland and Subalpine-Mountains 65K Well drainedBVery limitedVery limited
Cook Inlet Mountains-Boreal Alpine-Mountains 45K Well drainedVery limitedVery limited
Bristol Bay-Northern Alaska Peninsula Lowlands-Maritime Upland-Glaciated Rounded Mountains 36K Well drainedA/DVery limitedVery limited
Southern Alaska Peninsula Mountains-Maritime Upland-Volcanic Mountains and Lowland-Flood Plains and Stream Terraces 35K Somewhat excessively drainedBNot limitedVery limited
Interior Alaska Mountains-Boreal Subalpine and Alpine-Rounded Mountains, Ash Influenced 27K Well drainedCVery limitedVery limited
Interior Alaska Mountains-Boreal Upland and Subalpine-Glaciated Plains and Hills, Ash Influenced 20K Well drainedBSomewhat limitedVery limited
Southern Alaska Peninsula Mountains-Maritime Lowland-Coastal Plains 16K Very poorly drainedDVery limitedVery limited

What This Means

Building & Foundations

About 56% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.

Septic Systems

About 80% of soils are rated "very limited" for septic absorption fields. Despite good drainage overall, limitations may stem from shallow bedrock, steep slopes, or seasonal conditions. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.

Gardening & Agriculture

Well-drained soils on sloped terrain — good for most plants but watch for erosion. Terracing, contour planting, and mulching help retain moisture and topsoil. Drip irrigation is more effective than sprinklers on slopes.

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