Largo, Florida

Largo, Florida Largo, Florida

Water Quality in Largo, Florida

Watershed: Lake Seminole

What is the water quality like in Largo, FL?

Let’s dive deeper into what’s in Largo water.

What’s in Largo water?

Here are the top 5 chemical compounds in your water and what health issues they can potentially cause:

  1. Arsenic – Potential effect: Cancer
  2. Chlorate – Potential effect: Harm to the thyroid
  3. Haloacetic acids – Potential effect: Cancer
  4. Hexavalent Chromium – Potential effect: Cancer
  5. Total trihalomethanes – Potential effect: Cancer

These are five of the 21 contaminants analyzed by the Environmental Working Group (

5 of these contaminants are rated as exceeding EWG Health Guidelines.

See the What Can You Do? section below for all of the contaminants you can filter out and how to do it.

Where does Largo’s water come from?

Largo’s water comes from the Lake Seminole watershed.

All 22 EPA assessed water sources in the Lake Seminole watershed are in Impaired or Unknown condition. These include:

  • Allen Creek
  • Boca Ciega Bay
  • Bonn Creek
  • Cross Bayou Drain
  • Cross Canal
  • Direct Runoff to Bay
  • Direct Runoff to Intracoastal Waterway
  • Joe’s Creek
  • Lake Seminole
  • Lake Seminole Outlet
  • Long Bayou Runoff
  • Long Bayou/Cross Bayou
  • McKay Creek
  • Pasadena Lake
  • Pasadena Lake Outlet
  • Pinellas Park Ditches 1 and 5
  • Rattlesnake Creek
  • Sawgrass Lake
  • St. Joe Creek
  • Starkey Basin

Ideally, a water source would be rated in Good condition.

Whether a water source is in Impaired or Good condition refers to the quality of these uses:

  1. Drinking Water
  2. Aquatic Life
  3. Fish and Shellfish Consumption
  4. Recreation

Learn more from How’s My Waterway

See below for what you can do to improve Largo’s water.

Conclusion – What Can You Do?

Information about water quality can be surprising.

But there’s no reason to lose hope. There are things you can do in your household as well as things you can do at a community level.

In Your Household:

*Chlorination is an effective method of disinfecting/treating drinking water. You can then use a water filter to reduce the effects of chlorination byproducts to get the safest, cleanest water possible.

In Your Community:

Contact your local government officials and put pressure on them to invest in cleaner waterways and upgraded city water filtration and treatment.

Go to: to find contact information for your local officials.

Water Quality in Other Florida Cities

Florida Water Quality Page

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