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Clogged drain? What to try first and when to call

First decide whether it's one slow drain or several backing up at once. The answer changes what's safe to try. Written for homeowners in Greenville, Spartanburg, Anderson and Pickens counties.

Published Sources listed at the end Checked against Poison Control, CDC, EPA, MedlinePlus, ReWa, Spartanburg Water and Easley Combined Utilities guidance

Safety first

If sewage is coming up into a tub, shower or floor drain, stop using water in the house and keep people and pets away from it. Don't step into water near outlets, cords or the electric panel. Never mix drain cleaners or other cleaning products: Poison Control warns that mixing can cause poisonous fumes and serious breathing problems.

If someone is exposed to a drain cleaner: if they collapse, have a seizure, have trouble breathing or can't be awakened, call 911 immediately. For a splash in the eyes or on the skin, start rinsing right away with running water for 15 to 20 minutes, then get advice from Poison Control. If a cleaner was swallowed, don't make the person vomit; get poison advice immediately.

1. One slow drain, or several?

  • One sink, tub or toilet is slow: the clog is likely close to that fixture. See step 2.
  • Several drains back up at the same time, or water comes up in the lowest drain when another fixture is used: the main sewer line may be blocked. Stop running water, don't run more to test it, and call a licensed plumber. Gurgling on its own doesn't prove a main-line problem.

Spartanburg Water notes that a blockage can be in your private plumbing or in the sewer main in the street, and for a backup in a home it tells customers to contact a plumber. If you see sewage spilling outdoors, report it to the sewer provider serving your address; your water or sewer bill shows which one that is.

2. For a single slow drain

Before you try a plunger: don't plunge if a drain cleaner has been used, you don't know what's in the standing water, sewage is backing up, or there's an electrical hazard. Keep clear and tell the plumber what was poured in.

  • Stop using that drain so water doesn't overflow.
  • Clear only what you can see at the surface, such as hair on a sink or shower strainer, without reaching into standing water. Never put your hand into a garbage disposal.
  • A plunger made for that fixture is the usual first try. EPA lists a plunger or plumber's snake as an alternative to chemical drain cleaners. Stop if water rises toward the rim.
  • If it doesn't clear after a few tries, stop and don't keep forcing it.

3. Chemical drain cleaners: read this first

  • Some are highly corrosive. Poison Control says drain cleaners can cause chemical burns on the skin, and in the lungs if strong fumes are inhaled. MedlinePlus lists sodium hydroxide as the poisonous ingredient in some drain cleaners.
  • Never mix products. CDC says never to mix household bleach, or any disinfectant, with other cleaners, because the vapors can be very dangerous to breathe.
  • If you already used one and the drain is still clogged, don't plunge it: Pinellas County's utility advice is to use a plunger first, "though not after using any commercial drain opener." Don't add a second product or try to neutralize it. Keep children and pets away and tell the plumber exactly what you used.
  • If fumes cause symptoms, move to fresh air without putting yourself at risk. Don't stay in or go back into the room just to open a window.
  • If you use one, follow the label exactly. Poison Control advises ventilating the area and wearing rubber gloves and safety goggles with strong cleaners.

4. What not to pour or flush

  • Grease: ReWa explains that fats, oils and grease stick to the inside of sewer lines and harden, and that garbage disposals don't keep them out of the sewer system. Easley Combined Utilities notes that hot water and detergent only break grease up temporarily. Pour grease into a container, let it cool and harden, and put it in the trash.
  • Wipes: Spartanburg Water says diapers and baby wipes, even those labeled "flushable", belong in the trash. ReWa puts it simply: the only safe item to flush is toilet paper.
  • The cleanout: Spartanburg Water describes cleanouts as white plastic caps that cover the access to a home's sewer service line, and suggests keeping yours clearly marked and easy to reach. If sewage is backing up, leave opening it to a plumber.

5. Renting, or sharing a building?

Notify your landlord or property manager promptly, but don't delay emergency help or reporting a suspected public sewer spill while waiting for permission. In apartments, condos and townhomes, one blocked line can affect neighbors, so tell management and stop running water until it's checked.

6. When to call a licensed plumber

  • More than one drain is slow or backing up, or sewage comes up anywhere in the house.
  • The same drain clogs again and again.
  • A plunger didn't clear it after a few tries.
  • A chemical drain cleaner was used and the drain is still blocked.

Sewage spilling outdoors? Report it to your sewer provider as well.

7. Before you call

Note which drains are affected, when it started, and anything you've tried or poured in. If sewage reached your floors, take photos from a safe spot and keep receipts: Spartanburg Water suggests documenting expenses from a sewer problem. Our call-ready planner turns this into a one-line summary. Before work starts, check the plumber's license and ask for a written estimate.

8. How our referral line will work

When it opens, a short automated prompt will ask for your ZIP code. If an independent provider who serves your ZIP is available, the call will be connected. Availability isn't guaranteed, especially after hours.

We won't charge you for the referral; your phone carrier's usual rates will apply. The provider quotes the job. Not sure what to say? Get call-ready in three taps.

Sources