The Long Beach Fire Department received calls about a strong ammonia odor from the 600 block of West Anaheim Street shortly before 5 a.m.
A hazardous materials crew arrived on scene at 8 a.m. and shut the main valve, but not before a diffuser tank spewed up to 200 gallons of ammonia product. Authorities said some of the product got into a storm drain.
The leak was fixed and the spill was cleaned up.
No injuries were reported and no evacuations were ordered, but Long Beach fire officials said crews would likely be on scene for most of the day to monitor the situation. Air samples were taken to ensure public safety.
Fish and Wildlife officials and the U.S. Coast Guard were also looking into the situation.