If you own a home with a septic system or are thinking about buying a home with a septic system, you might want to save this column. Starting May 1, new Municipality of Anchorage, or MOA, regulations for septic systems go into effect that will definitely affect you.
Most homeowners don’t think about what happens to the wastewater generated from their everyday personal and household uses. For homeowners with a septic system, YOU are your own utility company.
Wastewater typically goes from the house out to a 1,000- to 1,250-gallon tank buried in the yard. Here the contents settle and start to decompose. The effluent, or wastewater, from the tank eventually flows out through a pipe to a buried drainfield, a specific area bedding material that filters effluent back into the ground. Alaska’s colder temperatures slow decomposition in the septic tank, so the MOA recommends pumping out the solids every two years; we think annual pumping is a better preventive measure. Removing the sludge from your septic tank needs to be routinely preformed. You never want sludge to overflow into the drainfield because that would damage the drainfield - resulting in a costly replacement.
Some of the new regulations affect the actual septic tank, which is a focal part of any septic system. One concern is that conventionally coated steel septic tanks degrade with time. Unfortunately a majority of Anchorage homes with steel septic tanks were built more than 20 years ago.
Once a steel tank reaches 20 years old, the MOA currently requires the tank liquid to be measured during an inspection when selling the home or upgrading the septic system. If the levels are below normal, this indicates the tank is leaking and needs to be replaced. At 30 years, the tank must be physically exposed to ensure its integrity. Unfortunately, engineers tell us there is a 90-percent failure rate with steel tanks this old. At this point, a better use of funds would be to install a new tank.
If a septic tank fails, the tank contents (the really nasty smelly stuff) seep back into the ground without proper filtration. This can cause all kinds of environmental health concerns, especially to the groundwater.
All new steel tanks will need to have polyurethane coatings, inside and outside. Ideally, the new coatings will help reduce the rate of corrosion caused by soil conditions or the interior effluent eating holes in the steel tank.
As manufacturers gear up to make new coated-steel, plastic, fiberglass or concrete tanks, they also are trying to figure out how to compete in the new marketplace. Steel tanks are traditionally installed, and contractors already have the equipment to move them into place. Yet steel tanks can rust. Plastic tanks don’t have the same rust concerns, but they cannot be buried as deeply, and require different bedding materials. Nor are plastic tanks as viable in wetter areas because they cannot be pumped if submerged in groundwater. Fiberglass tanks can be made for any burial conditions, but are more expensive to make.
The costs of concrete tanks are anticipated to be similar to the costs of steel, but the installation will be more expensive due to the equipment needed to move and place the bigger, heavier concrete tanks. Yet, concrete tanks have their positives. They don’t rust; they have less stringent bedding requirements, can be installed in groundwater and can withstand deeper burial.
Another change is a structural modification to all tanks. A 24-inch manhole access (on the first compartment) is required to provide better visual inspection and allow easier access for cleaning. Current tanks only provide a four-inch hole for pumping/cleaning, so the new manhole will truly make inspections and cleaning easier.
Unfortunately, the new coating and larger access manhole will almost double the cost of a steel tank. Currently a 1,000-gallon steel tank is about $1,720 and a 1,250-gallon tank about $1,980. The changes increase the cost of a steel tank an additional $1,500. Add to that the engineering fees and installation costs, and these changes boost tank replacement about $7,500 to $9,500 – not including landscape restoration.
Since septic tanks are buried, they are easy to forget. However as the owner of your own utility, consider making a monthly contribution to your rainy-day fund for septic system maintenance. This will also offset the large expense you’ll incur when you eventually need to replace the septic tank or upgrade the drainfield.