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Household Hazardous Waste


Household Hazardous Waste

The Household Hazardous Waste (HHW) Program provided by San Mateo County helps residents dispose/recycle their residential hazardous waste properly – for FREE!  County residents may drop off a full range of HHW at our collection facilities and events year-round every Thursday, Friday and Saturday (except major holiday weekends).

All waste collected is either reused, recycled, processed for energy recovery, or stabilized for proper disposal to achieve zero waste being landfilled.

What is Household Hazardous Waste (HHW)?

HHW is a waste from your home, that is toxic, corrosive, flammable or reactive, based on its chemical properties.  Products such as paint thinner, toilet bowl cleaner, and rat bait exhibit these hazardous characteristics.  It is illegal to dispose of such dangerous wastes in the regular trash or dump them down the drain, so use the San Mateo County’s HHW Program for proper disposal.

HHW Collection Facilities and Events

Any County resident may participate at any collection location. They are held Thursdays through Saturdays at the main Facility in San Mateo, while collection events occur in Daly City, East Palo Alto, La Honda, Menlo Park, Pacifica, Portola Valley, Redwood City and South San Francisco.  Here is a list of 2017 collection event locations. Sign up for occasional reminders for upcoming events. 

Residents must make an appointment for drop off due to participation limits at each location. There is a limit of 10 gallons or 50 pounds per appointment based on transportation regulations.  Contact us directly if you have more than that amount.​ State regulation also requires you stay inside your vehicle at all times. Staff will unload your vehicle for you while onsite.

General information

What We Do and Don’t Accept

The HHW Collection Facility is open to San Mateo County residents.  Residents must make an appointment for drop off due to participation limits at each location. There is a limit of 10 gallons or 50 pounds per appointment based on transportation regulations. 

NOTE: Empty containers are not hazardous waste and may be disposed of in the garbage—just leave the lids off so your waste hauler can see that the container is empty and non-hazardous.

General information



Why do I need an appointment?

We are limited to how many cars we can handle at each collection site. The appointments allow us to manage this limit, as well as minimize your wait in line. 

Why do you need my contact information?

We send you an appointment confirmation that includes the address and driving directions to the drop-off location.

General information

Free Product Give Away Program

Many of the items collected at our HHW Collection Events are still in good condition These products include common household cleaners, auto supplies, fertilizers, wood preservatives, stains and latex paint.  At our Product Give Away Program Warehouse, these products are given away to the public free-of-charge. 

Please take only what you need.


Where to Recycle Household Batteries

All batteries are considered hazardous waste in California when they are discarded. This includes batteries of all sizes from AAA, AA, C, D, button cell, 9 Volt, and more, both rechargeable and single-use.

Battery recyclers melt down spent rechargeable and household batteries in a high-temperature process, then reclaim materials such as nickel, iron, lead, cobalt, and cadmium.

Please tape the terminals of Lithium (Li) batteries before recycling to protect from fires. 

General information

Where to Recycle Fluorescent Lights

Fluorescent lights save electricity and are a good choice for energy conservation. However, all fluorescent lights contain a very small amount of mercury sealed within the glass tubing. This means the lights are toxic and can’t be put in the trash.

General information

Very Small Quantity Generator (VSQG) Program

Some businesses generate very little hazardous waste and may be eligible to participate in the Very Small Quantity Generator (VSQG) Program. The Program is designed to provide an inexpensive hazardous waste disposal option to these companies, non-profits, and other entities instead of contracting with a commercial hazardous waste management firm.

The Program operates by appointment only.