Restaurant and Commercial Kitchen Plumbing in Southwest Florida

Grease interceptors and grease traps

Every kitchen that sends fats, oils and grease (FOG) down the drain needs a device to catch it before it reaches the public sewer. The two common types are small grease traps, usually under or beside a sink inside the kitchen, and large in-ground grease interceptors, usually out back under a manhole lid. Utilities in our area draw the line between them at roughly 50 gallons of capacity, and the maintenance rules are very different for each.

Both work the same way. Warm greasy water enters, slows down, and cools. Grease floats to the top, food solids settle to the bottom, and the cleaner middle layer leaves through an outlet tee or baffle. When the floating layer gets too thick, or solids build up to the outlet, grease passes straight through and starts coating the building sewer and the city main downstream.

Most of what we fix on interceptors falls into a short list:

• Broken or missing inlet and outlet tees, which let grease short-circuit the tank
• Cracked or rusted baffle walls in older concrete units
• Lids and risers that let rainwater or irrigation runoff in, which pushes grease out early
• Undersized indoor traps that fill in a day or two at a busy location
• Dishwashers or food waste grinders piped into a trap that wasn’t sized for them
• Lines between the kitchen and the interceptor that are packed solid because nobody jetted them

Pumping is done by a licensed grease hauler, not a plumber. Our part is the plumbing on either side of the tank: the drain lines feeding it, the tees and baffles inside it, the outlet to the sewer, and replacing or resizing the unit when it no longer keeps up.

Local FOG programs in Lee, Collier, Cape Coral and Fort Myers

Which grease rules apply depends on who provides your sewer service, and that isn’t always the county you’re in. A restaurant in unincorporated Lee County on Lee County Utilities sewer answers to LCU. A place on the other side of the bridge may be on City of Cape Coral or City of Fort Myers sewer instead, and each of those cities runs its own utility and its own grease enforcement.

Lee County Utilities

LCU enforces Lee County Ordinance 14-24 on grease management. Under its program, interceptors over 50 gallons must be pumped at least every 90 days, or sooner if the floating grease layer on the outlet side passes 6 inches or settled solids pass 8 inches. Traps under 50 gallons must be pumped at least every 7 days, or sooner once grease and solids reach 20 percent of the unit’s volume. Maintenance reports are filed online by the customer or the hauler, and LCU inspects establishments periodically and can require more frequent pumping.

Collier County

Collier County’s pretreatment program sets pumping at least every 30 days for indoor traps and at least every 90 days for in-ground interceptors. Cleaning records have to be kept for at least three years and show the service date, the hauler, the disposal site and the volume or condition pumped. The county also requires approval before you use enzymes, emulsifiers or grease cutters, because those products tend to break grease loose in the trap only for it to set up again further down the line.

Cape Coral, Fort Myers and other city systems

Cape Coral and the City of Fort Myers each set their own pumping intervals, reporting and inspection routines for food service customers. Naples, Punta Gorda and other city utilities do the same. Before you sign a lease or change your pumping schedule, call the utility that bills you for sewer and ask for its current grease requirements in writing. We can look at what you have in the ground and tell you whether it’s realistic to meet them.

Hauler manifests and the ban on returning water to the trap

Florida tightened grease waste rules statewide in 2022 with Senate Bill 1110, which created section 403.0741 of the Florida Statutes. Grease haulers now need a state license from the Department of Environmental Protection, must take grease waste to a permitted or certified disposal facility, and must complete a service manifest every time they pump. The restaurant, as the originator, keeps signed copies of those manifests.

The law also prohibits returning separated water back into the trap or interceptor after pumping, a practice sometimes called gray water return. If a hauler offers to decant the tank and put the water back to save on disposal, that’s a violation, and the utility inspector will be looking at your manifests.

From a plumbing standpoint, the manifest trail is useful. When an interceptor keeps failing inspection right after it’s pumped, the manifests usually show whether the problem is the pumping frequency or something physical, like a broken outlet tee or a dishwasher that dumps scalding water and melts the grease cap.

Three-compartment sinks and prep sinks

The three-compartment sink is where a lot of kitchens get written up and where a lot of grease enters the system. Health rules require a way to wash, rinse and sanitize utensils by hand, and each compartment has to be big enough to fully submerge your largest pot or sheet pan. Drainboards on both ends need to be large enough to stage dirty and clean wares separately.

Plumbing problems we see on these sinks:

• Faucet that can’t reach all three bowls, so staff fill one bowl from a hose
• Hot water that runs lukewarm at the wash compartment because the heater or recirculation loop is undersized
• Leaking basket strainers or tailpieces dripping onto the floor under the sink
• Waste piping run in a way that makes the sink impossible to connect to the grease trap
• Missing or broken backflow device on a hose-thread faucet

Prep sinks used for washing produce or thawing food are a different animal. They have to drain indirectly through an air gap, and they shouldn’t share a drain with the warewashing sink in a way that lets dirty water back up into the prep bowl. Under the Florida Building Code, Plumbing, a three-compartment sink normally connects to the grease trap, while a dedicated prep sink connects indirectly to a floor sink.

Indirect waste, air gaps, floor drains and floor sinks

Anything that stores, prepares or holds food can’t be piped straight into the sanitary drain. If the drain ever backs up, sewage would flow right into the equipment. The code answer is indirect waste: the equipment’s drain line ends above a floor sink or other trapped receptor, with open air between the end of the pipe and the receptor’s rim.

That gap has to be at least twice the diameter of the drain pipe. An air break, where the pipe dips just below the rim of a standpipe, is allowed for some equipment but not for food preparation, handling or storage fixtures. Floor drains inside walk-in coolers and freezers also have to connect indirectly through an air gap, which surprises a lot of owners who assume the walk-in floor drain is just a regular drain.

Floor sinks

A floor sink is a square, trapped receptor set flush with the floor, usually with a half or three-quarter grate so drain lines can drop in. Ice machines, steam tables, prep sinks, beverage stations and condensate lines commonly discharge here. When a floor sink fills and overflows, it’s usually one of three things: the trap below it is clogged with grease and food, the trap has dried out and the drain is pulling sewer gas instead of draining, or the line downstream is partially blocked and every floor sink on that run backs up at once.

Floor drains

Floor drains in dish areas and cooklines take mop water, spills and hose-down water. They need trap primers or regular water to keep the trap sealed, and they should have removable strainers. A floor drain that smells is almost always a dry trap. One that gurgles when the dishwasher drains is telling you the branch line is restricted.

Hand sinks

The handwash sink is one of the most cited items on a Florida restaurant inspection, and much of it is plumbing. The sink needs hot and cold running water, delivered at a minimum of 100 degrees F through a mixing or combination faucet. It has to be accessible at all times, which means no buckets, no stacked boxes and no using it to dump coffee or rinse a mop.

From the plumbing side, the failures are predictable. The hot side takes minutes to come up to temperature because the sink is a long run from the water heater with no recirculation. A mixing valve sticks and the sink only gives cold. A self-closing or metering faucet runs for two seconds instead of the 15 seconds the code expects. The drain is slow because staff have been using it for food scraps. A new hand sink near a cookline is often the cheapest fix for an inspection finding that says there isn’t one close enough to the work.

Commercial water heaters and booster heaters

Restaurant hot water demand is spiky. Nothing for an hour, then a dish machine, a three-compartment sink and three hand sinks all pulling at once during the rush. Residential-style heaters that were fine for a small cafe will go cold when the menu or seat count grows. Sizing a commercial heater means adding up the gallons per hour of every fixture and machine at the temperatures they actually need, not just copying what was there before.

High-temperature dish machines sanitize with heat. The food code sets the final rinse at no more than 194 degrees F entering the manifold, and at least 180 degrees F for most machines, or 165 degrees F for a stationary rack, single-temperature unit. Since storing water that hot in a building heater is wasteful and a scald risk, most kitchens supply the building at around 140 degrees F and use a booster heater at the machine to bring the rinse water the rest of the way.

When a booster can’t keep up, the dish machine’s rinse gauge drops below spec and the health inspector will catch it. Typical causes are scale-coated elements, which is common on our area’s hard water, a failed thermostat, low incoming temperature from the main heater, or a booster that was undersized for the machine. Low-temperature chemical-sanitizing machines don’t need a booster, but they still need the main heater to deliver the wash temperature the manufacturer lists. We install and service tank and tankless commercial units; see our water heater service page for the equipment side.

Backflow protection on ice machines, soda and coffee

Any piece of equipment that connects to the potable water supply and could push something back into it needs backflow protection. In a kitchen, the big three are carbonated beverage dispensers, coffee and tea brewers, and ice machines.

Carbonated soda systems are the serious one. The carbonator mixes CO2 with water under pressure, and if carbonated water backs up into copper or brass piping, it forms carbonic acid that dissolves copper into the drinking water. The plumbing code requires beverage dispensers to be protected by an ASSE 1022 backflow preventer or an air gap, and the piping downstream of that device shouldn’t be copper or brass. Coffee machines and noncarbonated dispensers fall under the same ASSE 1022 or air gap requirement.

Ice machines need their drain piped indirectly to a floor sink through an air gap, and their supply should be protected according to the manufacturer and the local water purveyor. Chemical dispensers for dish machines, mop sinks and three-compartment sinks also need protection, such as an air gap, a reduced pressure assembly or a vacuum breaker mounted high enough above the flood rim.

Many utilities also require a testable backflow assembly at the building’s water service for food service customers, with annual test reports. Our backflow testing and repair page covers that annual cycle.

What a DBPR inspector checks on the plumbing side

In Florida, most restaurants are licensed and inspected by the Division of Hotels and Restaurants within the Department of Business and Professional Regulation. The division’s rules adopt the 2017 FDA Food Code by reference. Inspectors aren’t plumbing inspectors, but a lot of their findings send owners to a plumber. These are the plumbing items that come up most often:

• Handwash sink missing, blocked, without hot water or not reaching 100 degrees F
• Hose-thread faucets without a backflow device, including at mop sinks
• Condensate and other non-sewage liquids not drained the way the local plumbing authority requires
• Exposed sewer or waste lines running over food prep areas or food contact surfaces
• Leaks, standing water and slow drains under sinks and around floor drains
• Dish machine final rinse temperature or sanitizer below spec
• No mop or utility sink, or one without hot and cold water connected to the sanitary sewer

The division also requires plan review before a food service establishment is newly built, converted from another use, remodeled, or reopened after being closed for 18 months or more. That review looks at the same plumbing basics, and it’s a separate approval from the building permit.

Jetting kitchen lines

A cable machine will punch a hole through a grease clog and get you running again tonight. It won’t remove the grease coating the walls of the pipe, and the same line usually stops again within weeks. For kitchen drains, the better fix is high-pressure water jetting, which scours the pipe wall and flushes the grease out to the interceptor or sewer.

The lines that need it most are the branch from the three-compartment sink and dish area to the grease interceptor, the floor sink runs along the cookline, and the building sewer from the interceptor outlet to the main. In older strip centers along US 41 and the main corridors, those lines are often cast iron, and decades of grease and scale cut the inside diameter down a lot. A camera run after jetting shows whether the pipe is sound or whether there’s a belly, a root intrusion or a separated joint holding grease. More on that in our hydro jetting and sewer camera inspection pages.

Jetting on a schedule, timed with your interceptor pumping, tends to be cheaper than repeated emergency calls. It also helps with utility inspections, because the inspector can see the interceptor isn’t the only thing being maintained.

Scheduling work around service

A plumber on the cookline at 6pm on a Friday costs you covers. We’d rather plan the work for when you’re closed or slow: before opening, between lunch and dinner, or on the day of the week you’re dark. Jetting, interceptor tee replacements, booster heater swaps and new hand sinks can all usually be set up that way.

Our office hours are Monday to Friday, 8am to 5pm. Outside those hours we take urgent calls by phone when we can, so if a floor sink is overflowing during service, call and we’ll tell you honestly whether we can come out or what you can do to get through the night. Our after-hours plumbing page explains how that works.

Things you can do before we get there:

• Know where the main water shutoff and the gas shutoff for the kitchen are, and keep them clear
• Stop using the dish machine and three-compartment sink if floor sinks are backing up, since they feed the same line
• Don’t pour drain chemicals into a grease line; they rarely work and make the line unsafe to service
• Have your last grease hauler manifest handy so we know when the interceptor was pumped

Tenant buildouts and second-generation restaurant spaces

Many new restaurants in Southwest Florida open in a space that used to be another restaurant. That second-generation space looks like a shortcut, and sometimes it is. Often, though, the existing interceptor is too small for the new menu, the floor sinks are in the wrong places for the new equipment layout, and the water heater was sized for a sandwich shop, not a full kitchen with a dish machine.

Before you sign, we can scope the existing plumbing: camera the building sewer and the interceptor lines, check the interceptor’s size and condition, look at water heater capacity, and find out where the existing floor sinks and drains sit relative to your planned equipment. That turns into a list of what can stay and what has to change, which you can bring to the landlord negotiation.

On a full buildout we install the underground waste, vent and grease piping, floor sinks and drains, water distribution, water heaters, gas piping for the cookline and backflow devices, then coordinate inspections with the building department. The utility will often want to approve the interceptor size, and DBPR plan review runs on its own track. Our commercial plumbing page covers the broader range of work we do for businesses, and gas line plumbing covers ranges, fryers and other gas equipment.

Kitchen fixtures, what they require and how they fail

A quick reference for the fixtures that cause most restaurant plumbing calls. Exact requirements depend on your equipment, your utility and the code edition in effect when the space was permitted.