Amman Septic Designs Inc
Call Us at (360) 794-7809


Based in Monroe, WA



King County:

Feasibility Study / Perk Test  $ 850.00

Full Septic Design costs an additional  $ 5,650.00  (Note the design cannot be done without the "Feasibility Study / Perk Test" being done first; we will not use a feasibility study done by another designer and will not credit you money that you paid another designer).

(Fee includes any redesigns required to gain initial Health District Approval; Any Additonal Health District Fees will be the responibility of the client);

When its time to install the system there are a series of inspections required called the Stub out inspection, pressure test inspection, backfill inspection, and preparation/submittal of the asbuilt package into Public Health for their final approval on the installation; Note these are all required for you to get final approval on your septic system; If its for my approved design then I do not charge anything for these inspections and asbuilt preparation and submittal. These services are not part of my design fee since I do not charge for these services. If you decide to hire another designer to perform these services for any reason then you will not receive a "refund" from me in that I don't charge for these services.

Winter Water Table Review $ 6,500.00  (If required due to high winter water table conditions) * Note price is $ 7,500.00 for sites on Vashon Island that need a winter water table review.

Note: Prices are for single family residence designs only, call for multi-family and commercial rates, and please note that Health District Fees are in addition to the design fees quoted above.


King County Design process:

      The first step is to have a Septic System Feasibility Study performed on the property to determine if the site perks and if it does what type system the Health District is going to require; This Study costs $ 850.00.

      The next step is to apply for and acquire approval of a “Critical Area’s Ordinance” site plan from the King County Building Dept. They can do this for you if your site is very simple otherwise you'll need to hire your own consultant (see the links page for some great biologists).

      Note for property located within a City's Limits, the CAO Review must still be done and approved by the City. A copy of the letter from the City will need to be submitted with the Septic System Design Application to the Health District (note that an email from the City is no longer acceptable, it must be letter on their letterhead);

      After you have CAO approval for the site, then we can revisit the site and prepare the full septic system design and submit it to the Health District for their review and approval;

The Septic Design will cost

$ 5,650.00 (note that this amount is in addition to the $ 850.00 paid for the feasibility study; the design cannot be done without doing the feasibility study first) with an additional Health District Design Review fee of phskc fee link

It will take us about a week to prepare the Septic Design once we're on the property; The Health District will take between 8-12 weeks to review it; Once approved it will be valid for two years.

Note that prior to Septic Design Submittal to the Health District several paperwork items will need to be provided by you:

1. If the property is served by Public Water, then a Current "Certificate Of Water Availability" will need to be produced. Contact the water purveyor for this.

2. If the property is to be served by an Individual Well the rules have changed effective November 2015; The way the process now works is that you and I will determine a good well site on the property and I will show that on my septic design. Public Health will give us expedited review of the septic design and well site (versus a site that is served by public water); Once they have reviewed our design then they will issue out a "hold" letter that is not an approval, it is a "hold" letter; What it will state is that the septic design is ok and will be approved once the following have been completed: 1. The well needs to be drilled. 2. Declaration of covenant which describes the exact location of the well (which I will prep for you) will need to be signed in front of a notary and then recorded down in Seattle at the King County Recorder's office. 2a. A two hour pump draw down test must be done. If the well flows at less then 5 gpm then a four hour test must be done. well must produce at least 400 gallons per day             3. The water from the well needs the following tests done: a. Two separate samples to be tested for bacteria b. one sample to be tested for Nitrates c. one sample to be tested for Arsenic; Note that wells with arsenic higher then ten parts per billion can sometimes be used if treatment is installed in certain circumstances. Once this is all done and submitted then Public Health will approve the septic design. Note that the water samples must be collected either by the well driller or the water system engineer and they must fill out and sign a chain of custody form certifying that they pulled the samples and delivered them to the lab. Note if your well's 100 foot protective radius encumbers a neighboring property that the owner of that property will have to sign a restrictive covenant in order for your well site to be approved.

3. If the property is to be served by a Group "B" Water System then you should contact the water system controller to verify that the water system is up to date and can sustain another connection. We will need the official name and id number for the water system for the septic design submittal. If it is a proposed Group "B" Water Well then you will need to get it drilled and approved as such before I can prepare and submit your septic design.

Note: If you need assistance with the above, please feel free to contact us.