Septic system requirements in Anchorage, Alaska

The septic rules landplan.io applies in Anchorage, what a septic tank costs there, and the parcel data we hold.

Updated 6 October 2026

Design a septic system for an address in Anchorage

Alaska's state rules apply in Anchorage: landplan.io has no county rules of its own here. State rules: Reviewed See Alaska's rules

6system types permitted

1,000 gallonssmallest septic tank

Septic systems allowed in Anchorage

The system types landplan.io permits in Anchorage:

Mound System
Cut and Fill system
Deep trench system
Leach pit system
Leach field
Surface Discharge

Septic tank size in Anchorage

The daily design flow of a home: 150 gal/day per bedroom, at least 240 gal/day. The septic tank is sized from that flow:

Septic Tank: minimum size by daily design flow
Daily design flow	Minimum tank
up to 240 gal/day	1,000 gallons
240 to 360 gal/day	1,500 gallons
360 to 600 gal/day	2,000 gallons
600 to 720 gal/day	2,500 gallons
720 to 840 gal/day	2,750 gallons
840 to 920 gal/day	3,000 gallons
920 to 1,040 gal/day	3,250 gallons

Septic setbacks in Anchorage

Minimum distances
From	To	Distance
Polygon	Existing Septic Component to be Abandoned	5 ft

These are the values the landplan.io design engine applies in Anchorage. Confirm a design with the Alaska health department or your county's before you build.

Septic companies, designers and jobs in Alaska

Where the rules come from

The regulations and documents landplan.io's Anchorage, Alaska rules are read from:

18 AAC 72 - Wastewater Disposal (full chapter: general provisions, individual/on-site water and wastewater systems, conventional and alternative onsite wastewater systems, and definitions) (18 Alaska Administrative Code (AAC) 72.005 through 72.990 (all articles))

Near Anchorage

Questions

What septic systems are allowed in Anchorage?

landplan.io designs by Alaska's state rules there and permits: Mound System, Cut and Fill system, Deep trench system, Leach pit system, Leach field and Surface Discharge.

What size septic tank do I need in Anchorage?

landplan.io sizes the septic tank in Anchorage from the daily design flow: up to 240 gal/day: 1,000 gallons; 240 to 360 gal/day: 1,500 gallons; 360 to 600 gal/day: 2,000 gallons; larger flows need larger tanks. A home's design flow is 150 gal/day per bedroom, at least 240 gal/day.