Grenco Septic Systems and Excavation Services

Grenco Excavation installs a new septic tank.

Septic Tank Deterioration

Grenco Excavation installs a new septic tank.

I feel pretty confident saying nobody wants to spend more than they have to on a new septic system. So why install a new tank if there’s already one in place? While holding off on replacement may seem to be the frugal way to go, taking the time to install a new tank can make the most sense in the long run.

Here are a few reasons I feel it’s money well spent:

  1.  The gasses created in a septic tank deteriorate the concrete roof of the tank over time. This results in a thinner concrete roof and exposes the structural wire. Therefore weakening the structure which can result in cracks and possibly collapse.

2.  The older tanks used concrete baffles to absorb the energy of the black water entering the tank and to keep solids from carrying over to the leach field. Just like the roof, these baffles are exposed to the deteriorating gasses. On most of the older tanks we look at, the baffles have fallen off. Failed baffles can result in solids carrying over to the leachfield therefore shortening its lifespan.

Diagram showing a two compartment septic tank such as the type that Grenco installs.

  1.  The older tanks were single compartment. New tanks have two compartments. The first makes up 2/3 of the tank and is where the black water enters the tank. The solids stay in this side of the tank and the “clear” layer carries over to the second compartment. Here the effluent will lose some more of the total suspended solids before it makes its way to the leach field.


The new tanks we install are water tight. This prevents the black water from entering the water table before treatment. More importantly it prevents ground water from entering the tank and overdosing the leach field.

Tanks don’t last forever. Even if you don’t replace the tank now eventually you will have to. It’s going to be much more cost effective to do it while we are on site installing the leach field. It is much easier to replace the tank then as we will have all of our equipment ready to do the job.

If you have questions about your tank and need some advice on the best option to take when it comes to replacement, contact Grenco, we will be happy to help you make the best decision for your situation.

Snow covers pipes in an excavated leach field installed by Grenco

2017 News from GRENCO

January is almost over already and spring is officially 49 days away!

We took a little family time and welcomed in the New Year Grenon style…skiing!

We’ve been doing some work, cleaning & maintaining our equipment and working on our continued education this January.  It feels like the winter is cruising by and we’re excited, as 2017 is looking to be another busy year working with fantastic clients on interesting projects.   Of course we’re hoping for at least a few more ski days first though!

Looking for a little gardening design inspiration…
One of our favorite landscape design teams, Samantha & Neil Best of Magma Design Group, will be giving a presentation ‘Stems and Stones: A Love Story’ on Sunday, February 19th from 1-2 at the Towerhill Botanical Garden.  To learn more and register, click here.

It hasn’t been that bad and we’ve still been able to work a bit – after shoveling the 1″ of snow off this Eljens that we installed the previous day…we were able to finish up, get it inspected and cover it up before the next snow came!



A little continued education?  Yes!  We always look forward to the RINLA (RI Nursery and Landscape Association) Annual Meeting and this year didn’t disappoint!

If you haven’t been following us on Facebook, you might want to!

With gratitude,
Scott and the Grenco family