Septic FAQ

What are the answers:

COSA Information

Septic Information

What is a COSA?
What costs are associated with a COSA?
Other COSA questions.

What is a COSA?

The Certificate of On-Site Systems Approval (COSA) is issued by the Municipality of Anchorage (MOA) and serves as confirmation to a buyer and lending institution that the well and/or septic system serving a single family or duplex home have been inspected / tested by a professional engineer and were found to be in compliance with the applicable standards established by the MOA.

In August of 1998 the Municipal Assembly passed an ordinance requiring that in order to transfer a title on any property that is served by a well or septic system, a Certificate of On-Site Systems Approval must be obtained. The intent of the ordinance was to help protect the public health by insuring that septic systems are functional and not creating a health hazard. In addition, it ensures that well water quality is safe to drink and in sufficient quantity to meet the basic needs of the family purchasing the house.

What costs are associated with a COSA?

Septic Test with no well $600.00 (in MOA)
Well Test with no septic $500.00 (in MOA)
Both Septic & Well tested $800.00 (in MOA)
Lab fees for Wells $175.00
(Bacteria, Nitrates & Arsenic)
Municipality of Anchorage (MoA) $621.54


Other COSA questions:

Do you need to come inside my house?
-----> No, unless there is NO water access to the outside of the house.

Do I need to be there while you run the test?
-----> As long as all the septic pipes, the well, and water to the outside of the house are all accessible, then no you do not have to be present. You can always stay if you would like.

How long does the entire process take?
-----> Standard turnaround time inside the MoA is 3-4 weeks.

Is there any way we can get the COSA faster?
-----> Yes, we can rush water samples and MoA paperwork for an additional 60% of originals fees.

Do I need to pay upfront?
-----> If closing within 60 days of the adequacy test, PES can be paid out of closing.

How long is the test good for?
-----> Septic Well tests are good for 2 years from date of the test.

How long is the water sample good for?
-----> Bacteria and Nitrate samples are only good for 90 days. Arsenic samples are good for 1 year.

Do I need to pump the tank for the test?
-----> You do not need to pump the tank before we can run the test, but the MoA does require a pumping receipt within 1 year to approve the COSA.

Does PES offer discounts?
-----> Yes, on the engineering services PES provides. (one discount per client, per invoice)
~5% Military


What We Do

PES Services:

  • Civil Engineering
  • Structural Engineering
  • Environmental Engineering
  • Water/Wastewater Design
  • Sanitary Surveys
  • Onsite Septic Design
  • Home Inspections