Grease trap cleaning and installation in northern Utah

Both do the same job. They slow kitchen wastewater down so grease floats to the top and food solids sink to the bottom. The cleaner water in the middle flows on to the sewer.

A grease trap is the small one. It sits indoors, under or near a sink, and serves one fixture or a few. The plumbing code calls it a hydromechanical grease interceptor.

A grease interceptor is the large one. It is a tank buried outside the building, with lids at the surface, and it serves the whole kitchen. The plumbing code calls it a gravity grease interceptor.

People use "grease trap" for both, and so do we on this page. The difference matters for cleaning. A small trap can be cleaned by hand. A buried interceptor has to be pumped out by a vacuum truck.

Your sewer provider sets the schedule, so check with their pretreatment program first. Salt Lake City's rules show how providers write them. Salt Lake City Public Utilities requires grease traps to be completely cleaned at least every 30 days. Gravity grease interceptors must be cleaned at least every 90 days, or when grease and solids reach 25% of capacity in the first chamber. The city calls this the 25% rule.

The reason for the rule is simple. As grease and solids fill the tank, water has less room and moves through faster. Grease no longer has time to separate, and it passes into the sewer.

Kitchens that fry and grill all day fill a trap faster than a coffee shop does. We measure the grease and solids at each service, so your schedule rests on numbers.

Keep a log of every cleaning and repair, and keep it where an inspector can see it. Salt Lake City Public Utilities requires food service establishments to keep records of all grease control equipment maintenance, cleaning, and repairs on site for at least 5 years. The records must be readily available for inspection on request. The city also requires kitchens to display its BMP poster, which lists the required kitchen practices.

Other sewer providers have their own rules, so ask yours. A log that holds up has the same things everywhere:

• The date of the service and who did it.
• How much grease and solids were in the trap.
• The condition of the baffles, lids, and gaskets.
• Where the waste was taken.

Ask for a written record after every service and file it the same day.

A proper cleaning empties the whole trap. Skimming the top layer is not a cleaning.

1. We open the lids and measure the depth of the grease layer and the solids.
2. We remove everything in the trap: grease, water, and solids.
3. We scrape and wash the walls, the baffles, and the inlet and outlet.
4. We inspect the baffles, fittings, lids, and gaskets, and the flow control device on a small trap.
5. We refill the trap with clean water. It needs water to work.
6. We run the kitchen fixtures and check the flow.
7. The waste is hauled to an approved disposal site, and the service goes on your log.

Ask where the waste goes and keep that with your records. We schedule the work around your kitchen hours, because the sinks that drain to the trap cannot be used during the cleaning.

A trap that is overdue shows it in the kitchen first. Watch for:

• Sinks and floor drains that drain slowly.
• A rotten smell near the trap or the floor drains.
• Water or grease coming up at a floor drain.
• Grease visible at the trap outlet or in a cleanout past the trap.
• A grease and solids layer near a quarter of the trap's depth.
• A cleaning date that has passed.

An overdue trap sends grease into the building drain and the public sewer. Salt Lake City Public Utilities calls grease a leading source of sewer pipe blockages. It builds up on the pipe wall, narrows the pipe, and causes odors.

If drains stay slow after the trap is cleaned, the grease is already in the line past it. That line needs hydro jetting.

We give free estimates. These are the things that change the price of grease trap work:

• Size and type. A small indoor trap is a quick job. A buried interceptor holds far more and needs a vacuum truck.
• Access. Lids under equipment, in a parking lot, or sealed shut take longer to open.
• How full it is. An overdue trap holds hardened grease that takes more work to remove.
• How often it is serviced. A regular schedule keeps each visit short.
• Repairs. Broken baffles, corroded lids, and worn gaskets add parts and labor.
• Line cleaning. Drain lines past the trap may need hydro jetting.
• Installation. A new or larger unit adds sizing, plan review, permits, and sometimes excavation.

You get the estimate before any work starts.

A kitchen needs a new or larger unit when the one in place cannot keep grease out of the sewer. Common reasons:

• A new restaurant is being built, or a space is being turned into a kitchen.
• The menu or the volume changed, and the trap now fills well before its cleaning date.
• A steel trap has rusted through, or the baffles are broken.
• An inspector from the sewer provider has required an upgrade.

Get the size approved before anything is built. In Lehi and the other north Utah County cities served by Timpanogos Sanitary Sewer District, pretreatment staff and the member city review the construction drawings before a business builds or remodels. That review keeps an owner from building a kitchen and then having to change it after the first inspection.