Mississippi River at Thebes, IL

Measures water acidity or alkalinity on a scale of 0-14. Neutral is 7. Most fish thrive in 6.5-8.5 range.

Common fecal coliform bacteria indicating possible sewage contamination. EPA recreational limit: <126 MPN/100mL.

Water temperature directly affects fish metabolism and activity. Optimal range varies by species.

Amount of oxygen dissolved in water. Essential for fish survival. 6+ mg/L is ideal for most fish species.

Measures water cloudiness caused by suspended particles. Lower values indicate clearer water. <25 NTU is good.

Water temperature directly affects fish metabolism and activity. Optimal range varies by species.

Measures dissolved ions and minerals in water. Indicates salinity and pollution levels. Freshwater: 100-500 µS/cm.

Measures water cloudiness caused by suspended particles. Lower values indicate clearer water. <25 NTU is good.

Amount of oxygen dissolved in water. Essential for fish survival. 6+ mg/L is ideal for most fish species.

Common fecal coliform bacteria indicating possible sewage contamination. EPA recreational limit: <126 MPN/100mL.

Conductivity (µS/cm) - a water quality measurement. Contact local authorities for specific safety guidelines.

Measures dissolved ions and minerals in water. Indicates salinity and pollution levels. Freshwater: 100-500 µS/cm.