Beach · Calhoun County · TX
Is Port Alto Public Park safe to swim?
Recent heavy rain may have spiked bacteria since the last clear sample.
Updated July 19, 2026 · Texas beach program (EPA BEACON)
SwimZone for iPhone · launching soon
Know before you get in at Port Alto Public Park.
Get an alert the day a bacteria or algae advisory goes up.
What's in the water at Port Alto Public Park right now
As of July 19, 2026, Port Alto Public Park in Calhoun County, Texas carries a swim caution. Blue-green algae are not currently monitored at this water. No fecal-bacteria advisory is posted (state beach program). Rainfall over the past week totaled 2.5 in, which can wash bacteria and nutrients into the water.
Blue-green algae at Port Alto Public Park
Port Alto Public Park is a lake in Calhoun County, Texas. Blue-green algae are not currently monitored at this water.
Blue-green algae (cyanobacteria) blooms are most common from midsummer into early fall, when the water is warm, calm, and rich in nutrients from runoff. They can produce toxins that make people sick and can be rapidly fatal to dogs, so skip water that looks green, scummy, or like spilled paint, and keep children and pets out of it.
Frequently asked: swimming in Port Alto Public Park
- Is it safe to swim in Port Alto Public Park right now?
- Port Alto Public Park carries a swim caution today. Blue-green algae are not currently monitored at this water. Conditions can change quickly with wind, heat, and rain, so check the posted signs and look at the water before you get in.
- Does Port Alto Public Park have blue-green algae (cyanobacteria)?
- Blue-green algae are not currently monitored at Port Alto Public Park. Watch for green, blue-green, or paint-like scum and avoid the water if you see it.
- Can dogs swim in Port Alto Public Park?
- No bloom is detected at Port Alto Public Park today, but dogs are much more vulnerable to blue-green algae than people, and blooms can form within hours. Always keep dogs away from water that looks green, scummy, or discolored, and rinse them off after swimming.
- How many Texas lakes and beaches have swim advisories today?
- Today, 78 Texas waters are under a swim advisory and 86 more warrant caution, out of 399 monitored waters SwimZone tracks in the state.
- How is Port Alto Public Park's water quality measured?
- SwimZone builds this read from EPA CyAN satellite imagery for blue-green algae, official beach and fecal-bacteria advisories where a program monitors Port Alto Public Park, and a recent-rainfall overlay, all refreshed daily. It was last updated July 19, 2026.