Thousands of fish were found dead Friday in south Mexicali’s Laguna Xochimilco lagoon.

The site has been targeted by now Governor Marina Avila for rehabilitation since her mayorship term.

According to the state Public Utilities Commission of Mexicali said the deaths were caused by a phenomenon named thermal rollover.

This phenomenon that normally occurs in the first or second week of September occurs when water temperature and acidity increases during showers.

Also, ran moves sediments from the bottom of the lagoon and decreases oxygen.

The commission’s Control Laboratory manager Abraham Castro said rains came almost three weeks this year.

Low oxygen and high temperatures especially affect the silver sardine that lives in Mexicali’s lagoon system and the Rio Hardy River.

Water testing showed normal parameters, Castro said. Commission staff inspected the lagoon and found no illegal discharge of wastewater or issues with the wastewater system.