# Grease Trap Requirements for Houston Restaurants: What the City Expects, How Often to Pump, and the Plumbing Problems a Neglected Trap Causes

*Published 2026-10-15 by Hugo Plumbing, Houston, TX.*

Houston grease trap rules for restaurants: interceptor types, the 25 percent pumping rule, manifests, which fixtures drain to it, failure signs, market costs.

A grease trap is the one piece of plumbing in a Houston restaurant that the city, the health inspector, the landlord, and the dinner rush all care about at the same time. It is also the one that gets forgotten until the floor drain by the dish pit starts to back up on a Friday night.

This guide covers what the City of Houston generally requires of food service establishments, the two kinds of interceptors and which one your kitchen probably needs, how often to pump and how to prove you did, which fixtures have to drain through it, the plumbing failures a neglected interceptor causes, who pays when it does, and what the work costs in the Houston market. The rules here are described in general terms. Ordinances change, suburbs have their own programs, and plan reviewers have the final say, so confirm the current requirements with the city before you build, remodel, or sign a lease.

## Why Houston Regulates Grease

Fats, oils and grease, which the industry shortens to **FOG**, leave a kitchen as a warm liquid and arrive in the sewer as a cold solid. They coat the inside of the building lateral, then the city main, and they catch everything else that passes. A main that has narrowed with grease backs up into the lowest connection on the line, which is often a restaurant floor drain, and when a main overflows into the street it is a **sanitary sewer overflow** that the city has to report and clean up.

That is why the City of Houston runs a FOG program. In general terms, Houston Public Works oversees the sewer side and the interceptor requirements, the Houston Health Department sees the kitchen during food service inspections, and both can ask to see the interceptor and the pumping records. Food service establishments that discharge to the city sewer are generally required to:

- Have a **grease interceptor sized to the kitchen**, approved at plan review.
- **Maintain it** so grease and solids never exceed the allowed depth.
- **Keep pumping manifests on site**, usually for a set number of years, and produce them on request.
- Route the right fixtures through it and keep the wrong ones out.

Restaurants in Katy, Pearland, Sugar Land, Pasadena, Bellaire, and the unincorporated districts answer to their own city or MUD, and the specifics differ. Everything below describes the Houston pattern; your inspector describes your rules.

## The Two Kinds of Interceptors

The word "grease trap" gets used for both devices, and the difference matters because the city generally expects a specific one.

**Hydromechanical grease interceptors** are the small boxes under or beside a sink, typically 20 to 100 gallons, that slow the water down so grease floats and solids sink before the water leaves. They are indoor, they are cheap, and they fill fast. They are generally accepted for very light-use kitchens: a coffee shop with a single prep sink, a bar that does not fry, a small deli. They need cleaning weekly or more, often by staff, and the grease has to be disposed of properly, never down a drain.

**Gravity grease interceptors** are the large in-ground tanks, typically 500 to 1,500 gallons and sometimes larger, set outside the building with lids in the parking lot or a side yard. Water enters one end, grease rises and solids settle across two or three compartments, and clearer water leaves through an outlet tee. This is what the city generally expects for a full-service restaurant, anything with a fryer, a wok line, a commissary, or a grocery with food prep. They are pumped by a licensed grease hauler with a vacuum truck.

Which one your kitchen gets is not your call to make alone. The interceptor is sized by the engineer or plumber on the plans from the connected fixtures and their flow, following the plumbing code Houston uses, and the plan reviewer approves it. A kitchen that outgrows its interceptor, because the menu changed or a second fryer went in, is a common reason for a violation that nobody saw coming.

## The 25 Percent Rule and the Manifest

The maintenance benchmark that Houston and most Texas cities use, and the one the grease haulers work from, is the **25 percent rule**: pump the interceptor when the floating grease layer plus the settled solids reach 25 percent of the total liquid depth. Past that point the interceptor stops separating and grease passes straight through.

What that means on a calendar depends entirely on the kitchen:

| Kitchen type | Typical pumping interval (varies, confirm with your hauler) |
|---|---|
| Small under-sink trap, light use | Weekly to every two weeks, cleaned by staff |
| In-ground interceptor, sandwich or salad concept | Every 2 to 3 months |
| In-ground interceptor, full-service with fryers | Every 4 to 8 weeks |
| In-ground interceptor, wok line, barbecue, fried chicken, high volume | Monthly, sometimes more often |

The city generally does not care which date you picked. It cares that you were under 25 percent when the inspector opened the lid, and that you can prove a pattern of maintenance. That proof is the **manifest**: the document the licensed hauler leaves after each pumping showing the date, the volume removed, the hauler's registration, and where the grease was taken for disposal. Keep every manifest in a binder or a folder the manager can find. An inspector who asks for manifests and gets a shrug has already found a violation, even if the interceptor itself looks fine.

Two practices that get kitchens in trouble: **skimming** instead of pumping, where a hauler removes only the top grease layer and leaves the solids, which the city generally does not count as a full pump-out; and **enzymes, bacteria and emulsifying additives**, which are generally discouraged or prohibited by municipalities because they do not remove grease, they liquefy it so it passes the interceptor and hardens downstream in the city's main.

## Which Fixtures Drain Through It

The plans decide this, and the inspector checks it. In general terms, anything that can carry grease goes through the interceptor:

- Three-compartment sinks, pot sinks, and pre-rinse stations
- Kitchen floor drains and floor sinks under the cook line and dish area
- Mop sinks
- The dishwasher, often through a solids interceptor first so food waste does not fill the main interceptor
- Prep sinks and, in some jurisdictions, hand sinks in the prep area
- Can washes and outdoor grease bin pads

What never goes through it: restroom toilets, urinals and lavatories, because the interceptor is not a septic tank; roof drains and storm water, because rain would flush the grease straight through; and any drain outside the food service area.

The common violation is the fixture that got added after plan review, a second prep sink or a floor drain under a new fryer, that was tied into the nearest drain line instead of one that leads to the interceptor. If you are adding equipment, the drain route is part of the job. Our [permit guide](/blog/do-i-need-a-permit-for-plumbing-work-in-houston) covers when that kind of change needs a permit.

## What Goes Wrong

A neglected interceptor announces itself in a predictable order.

**Slow floor drains and gurgling.** The interceptor is full or the line to it is coated, and the kitchen drains are the first to feel it. Staff start using a plunger on a floor drain, which is a sign to call before the rush, not after.

**Sewer smell in the dining room.** A full interceptor off-gasses, and a dry or siphoned floor drain trap lets the smell in. If it comes and goes with the weather or the lunch rush, the interceptor is usually involved. Our [sewer smell guide](/blog/why-does-my-house-smell-like-sewer) covers the trap side of that problem.

**Backups during service.** Water comes up the floor drain or the floor sink under the dish machine. This is the one that closes kitchens. The interceptor has passed its limit and grease has narrowed the building lateral, or the lateral itself has failed.

**Grease past the interceptor.** Once FOG leaves a full interceptor it hardens in the lateral, usually at the first fitting or the first flat stretch. A snake punches a hole through it; [hydro jetting](/services/hydro-jetting) scours the pipe wall back to its full diameter, which is why jetting is the standard for kitchen lines. Our [hydro jetting vs snaking guide](/blog/hydro-jetting-vs-snaking-houston) explains why the cheaper option keeps coming back.

**Broken internals.** Baffles crack, and the inlet and outlet tees rust or collapse, especially on older concrete interceptors in the Heights, Montrose, Midtown and along Washington Avenue where the tank may be decades old. A missing outlet tee means the interceptor is just a holding tank and grease flows straight out. A hauler who notices this during a pump-out should tell you; a camera through the outlet confirms it.

**Lids and tanks in the parking lot.** Sunk, cracked, or missing lids are a trip hazard and a stormwater problem. After a Houston downpour, an interceptor with a failed lid or a cracked tank fills with runoff and overflows grease across the lot. Buildings along Bellaire Boulevard and in other flood-prone corridors see this every storm season.

**The lateral itself.** Older restaurant buildings often still have the original cast iron, and a line that has carried grease and dish-machine chemicals for sixty years is rough, scaled, and often cracked. Jetting clears the grease; a [sewer camera inspection](/services/sewer-camera-inspection) shows whether the pipe underneath is the real problem. Our [cast iron guide](/blog/cast-iron-pipes-older-houston-homes) describes what that pipe looks like from the inside, and the [sewer line repair cost guide](/blog/sewer-line-repair-cost-houston) covers what fixing it involves.

Beyond the plumbing, the consequences are the ones a manager fears: a notice of violation from the city, a required pump-out and reinspection, fines, a health inspection that goes badly because the floor drain is backing up, and in the worst case a kitchen closed until the line is clear and the interceptor is working.

## Opening a Restaurant or Changing the Menu

A new food service establishment, a change of use from retail to restaurant, and often a major remodel all generally go through **plan review**, where the interceptor is sized from the connected fixtures and shown on the drawings, then installed, inspected, and tied in before the kitchen opens. Taking over an existing restaurant does not mean the existing interceptor is adequate; if the concept changes from salads to fried chicken, the city may require a larger one.

Budget time for this. An in-ground interceptor is excavation, a concrete or fiberglass tank, inlet and outlet piping, a sampling port where required, lids rated for traffic if they sit in the lot, and inspection before backfill. Doing it after the kitchen is built means tearing out what was just finished. Our [new construction and remodel plumbing](/services/new-construction-and-remodel-plumbing) team works from the plans with the engineer and the reviewer so the interceptor is right the first time. Where the water supply side needs a backflow preventer, which is common on commercial kitchens, our [backflow guide](/blog/what-is-a-backflow-preventer-houston) covers that requirement.

## Tenant or Landlord?

The lease decides, so read it before the first backup. The usual pattern in Houston commercial leases is:

- **Tenant** handles routine maintenance: pumping, cleaning, manifests, keeping staff from pouring grease down drains, and clearing backups caused by kitchen operation.
- **Landlord** owns the interceptor as part of the building and generally handles structural failures: a collapsed tank, a failed lid in the common parking lot, a broken outlet tee, or a lateral that has rotted through.
- **Shared laterals** in multi-tenant strips are where the arguments live. If three kitchens share one line and it backs up, the camera footage showing grease from one suite versus a collapsed pipe is what settles who pays.

Get the diagnosis in writing when it happens. A written finding of cause from a licensed plumber is what the lease dispute, and sometimes the insurance claim, turns on. Our [landlord and tenant repairs guide](/blog/landlord-or-tenant-who-pays-for-plumbing-repairs-texas) covers the residential version of this question, and the logic carries over.

## A Maintenance Checklist

- **Daily:** scrape plates and pans into the trash before rinsing; keep strainers in every sink and floor drain; no grease or fryer oil down any drain, ever. Fryer oil goes to the recycling bin outside.
- **Weekly:** clean under-sink traps if you have them; walk the floor drains and listen for gurgling; check the outdoor lid for damage and standing water.
- **Monthly to quarterly:** full pump-out by a licensed hauler at the interval that keeps you under 25 percent; file the manifest the same day.
- **Annually:** have the interceptor internals inspected (baffles, tees, lid, tank condition) and the building lateral jetted and cameraed, especially in older buildings.
- **Any time the menu or equipment changes:** confirm the interceptor is still sized for the kitchen and every new fixture drains to it.
- **Train every new hire** on what goes down the drain. Most grease problems are a staff habit, not a plumbing defect.

## What It Costs in Houston

A licensed grease hauler pumps the interceptor and hauls the grease. Hugo Plumbing handles the plumbing side: the kitchen lines, the interceptor's inlet and outlet plumbing, backups, repairs, and new installations.

| Service | General Houston market, Oct 2026 |
|---|---|
| Pump-out, small indoor hydromechanical trap | $150 to $350 per visit |
| Pump-out, 1,000-gallon in-ground interceptor | $300 to $700 per visit, more for heavy solids or emergency timing |
| Hydro jetting a kitchen drain line or lateral | $400 to $1,200, by length and access |
| Sewer camera inspection (Hugo published price) | $295 to $350 |
| Replace an under-sink hydromechanical interceptor | $800 to $2,500 installed, by size |
| Repair interceptor internals (outlet tee, baffle, lid) | $500 to $3,000, by part and access |
| Install a new in-ground gravity interceptor | $8,000 to $30,000 or more; excavation, tank size, traffic-rated lids, and tie-in drive the range |
| After-hours emergency backup clearing | $500 to $1,500, by what it takes to open the line |

What moves the numbers: how deep the interceptor sits, whether the lids are under parking, how long and how old the lateral is, how much grease has hardened in it, and whether the job is during business hours or at 10 p.m. on a Saturday.

Hugo Plumbing's [commercial plumbing](/services/commercial-plumbing) accounts can be billed, the estimate visit is free with no trip or diagnostic fee, and every job is quoted as one flat written price before work starts. Hydro jetting and camera work are done in-house, permits and inspections are included when the city requires them, and the work carries at least a one-year warranty with extended coverage by job type; drain cleaning is the exception, since the condition of an existing line is outside anyone's control. Technicians speak Spanish, which matters on a lot of Houston kitchen crews.

## When It Is Backing Up Right Now

Stop running the dish machine and the sinks that drain to the interceptor. If the backup is coming from a floor drain, keep traffic off it and put down absorbent. Do not pour anything down any drain to "clear" it. Then call the [24/7 emergency line](/services/emergency-plumbing) at (713) 409-7176, call or text, and tell us it is a commercial kitchen with an interceptor so the truck comes with the jetter. A [drain cleaning](/services/drain-cleaning) visit during service is expensive in lost covers; the same visit the morning after the first slow drain is not.

The interceptor is the cheapest part of the system to maintain and the most expensive to ignore. Pump on schedule, keep the manifests, keep grease out of the drains, and have the line jetted and cameraed once a year before the inspector or the dinner rush finds the problem for you.

## Frequently Asked Questions

**Does a restaurant in Houston have to have a grease trap?**

Generally yes. The City of Houston runs a fats, oils and grease program, and food service establishments that discharge to the city sewer are generally required to have a grease interceptor sized to the kitchen, keep it maintained, and keep pumping records on site for inspection. The device type depends on the kitchen: a small under-sink hydromechanical trap for a very light-use kitchen, an in-ground gravity interceptor for most full-service restaurants. New builds and changes of use go through plan review, where the interceptor is sized and approved before the kitchen opens. Confirm the current ordinance and sizing with the city, because the details change and suburbs have their own rules.

**How often does a grease trap need to be pumped in Houston?**

The common benchmark is the 25 percent rule: pump when accumulated grease and solids reach a quarter of the liquid depth of the interceptor. For many Houston restaurants that works out to every one to three months for an in-ground interceptor, and much more often, sometimes weekly, for a small under-sink trap. Heavy fryer and wok kitchens fill faster than a sandwich shop. The city generally expects you to pump at whatever interval keeps you under 25 percent, not at a fixed calendar date, and the manifests from each pumping are how you prove it.

**What fixtures have to drain through the grease interceptor?**

Generally everything in the kitchen that can carry grease: the three-compartment sink, pre-rinse and pot sinks, hand sinks in the prep area in some jurisdictions, mop sinks, kitchen floor drains and floor sinks, and often the dishwasher, either directly or through a solids interceptor first. Restroom fixtures never go through it, and neither does roof or storm drainage. Which fixtures the plans route to the interceptor is decided at plan review, and a kitchen that adds a fixture later without rerouting it to the interceptor is a common inspection finding.

**What happens if a grease trap is not maintained?**

Inside the building, the first signs are slow floor drains, a sewer smell in the dining room, and backups in the kitchen during the dinner rush. Grease that gets past a full interceptor cools and hardens in the building lateral and eventually the city main, which is why the city inspects. Consequences generally run from a notice of violation and required pumping, to fines, to a failed health inspection or a shutdown while the kitchen is cleared. The plumbing bill is usually larger than the pumping you skipped, because the line has to be hydro jetted and the interceptor often needs repair.

**Who pays for grease trap problems, the restaurant tenant or the building owner?**

It depends on the lease, but the usual pattern is that the tenant is responsible for routine maintenance, meaning pumping, cleaning, and keeping manifests, while the landlord owns the interceptor as part of the building and handles structural failures such as a collapsed tank, a broken lid in the parking lot, or a failed outlet tee. Backups in the shared building lateral are often argued over, and a camera inspection that shows grease from one kitchen versus a broken pipe usually settles it. Read the lease before the problem, and get the diagnosis in writing when it happens.

If the dish pit drain won't go, call Hugo.

## Frequently Asked Questions

### Does a restaurant in Houston have to have a grease trap?

Generally yes. The City of Houston runs a fats, oils and grease program, and food service establishments that discharge to the city sewer are generally required to have a grease interceptor sized to the kitchen, keep it maintained, and keep pumping records on site for inspection. The device type depends on the kitchen: a small under-sink hydromechanical trap for a very light-use kitchen, an in-ground gravity interceptor for most full-service restaurants. New builds and changes of use go through plan review, where the interceptor is sized and approved before the kitchen opens. Confirm the current ordinance and sizing with the city, because the details change and suburbs have their own rules.

### How often does a grease trap need to be pumped in Houston?

The common benchmark is the 25 percent rule: pump when accumulated grease and solids reach a quarter of the liquid depth of the interceptor. For many Houston restaurants that works out to every one to three months for an in-ground interceptor, and much more often, sometimes weekly, for a small under-sink trap. Heavy fryer and wok kitchens fill faster than a sandwich shop. The city generally expects you to pump at whatever interval keeps you under 25 percent, not at a fixed calendar date, and the manifests from each pumping are how you prove it.

### What fixtures have to drain through the grease interceptor?

Generally everything in the kitchen that can carry grease: the three-compartment sink, pre-rinse and pot sinks, hand sinks in the prep area in some jurisdictions, mop sinks, kitchen floor drains and floor sinks, and often the dishwasher, either directly or through a solids interceptor first. Restroom fixtures never go through it, and neither does roof or storm drainage. Which fixtures the plans route to the interceptor is decided at plan review, and a kitchen that adds a fixture later without rerouting it to the interceptor is a common inspection finding.

### What happens if a grease trap is not maintained?

Inside the building, the first signs are slow floor drains, a sewer smell in the dining room, and backups in the kitchen during the dinner rush. Grease that gets past a full interceptor cools and hardens in the building lateral and eventually the city main, which is why the city inspects. Consequences generally run from a notice of violation and required pumping, to fines, to a failed health inspection or a shutdown while the kitchen is cleared. The plumbing bill is usually larger than the pumping you skipped, because the line has to be hydro jetted and the interceptor often needs repair.

### Who pays for grease trap problems, the restaurant tenant or the building owner?

It depends on the lease, but the usual pattern is that the tenant is responsible for routine maintenance, meaning pumping, cleaning, and keeping manifests, while the landlord owns the interceptor as part of the building and handles structural failures such as a collapsed tank, a broken lid in the parking lot, or a failed outlet tee. Backups in the shared building lateral are often argued over, and a camera inspection that shows grease from one kitchen versus a broken pipe usually settles it. Read the lease before the problem, and get the diagnosis in writing when it happens.

## About the Author

Hugo Plumbing is a licensed, insured, family-run plumbing company in Houston, Texas providing residential and commercial plumbing repair, replacement, and installation, with 24/7 emergency service. Services: https://hugoplumbingtx.com/services · Book: https://book.housecallpro.com/book/Hugo-Plumbing/a36279ec67c14456b0b25f1f992b2f4e?v2=true · Call: (713) 409-7176

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