[1]: 7 & A-15 The Acelhuate River has a drainage basin of 414 sq mi (1,070 km2), covering 5.1 percent of the country's land area,[3] and is 37 miles (60 km) long.

[8][9]: 42–43  In 1576, an oidor (judge) of San Salvador wrote to Spanish king Philip II describing the river's water as "very good and clear and without bad taste" ("muy buena y clara y sin ningún mal sabor").

In 1820, San Salvador council member Mariano Francisco Gómez reported to the Spanish parliament that the city's residents bathed in the river's waters and caught fish, mollusks, pearls, tortoiseshell, and murex.

[2] On 12 June 1922, heavy rains caused the Acelhuate River to overflow in parts of San Salvador and Colón.

[2][5] Industrial materials such as iron, arsenic, lead, mercury, and zinc are dumped into the river by factories.

[15] According to Salvadoran government documents, the Acelhuate River began to experience high levels of pollution of contamination during the mid-1900s.

A 1979 study of the Acelhuate River conducted by the Ministry of Agriculture and Livestock [es] and the Land Resources Development Center of the Overseas Development Administration of Great Britain described the pollution as "chronic" ("crónica") and as posing a health hazard to people living near the river.

The survey also concluded that decontaminating the river through reverse osmosis would not be possible due to high levels of organic chemical compounds in the water.

[17] On 20 February 2024, the Legislative Assembly of El Salvador approved funding for CEL to construct such a biogas electric power plant on the Acelhuate River near Ciudad Delgado and Cuscatancingo with the assistance of Saudi Arabian investors.