Foul odor is not harmful says South Coast Air Quality Management
The South Coast Air Quality Management District (AQMD) said that the foul odor caused by an algae bloom in the Santa Margarita Water District’s Upper Oso Reservoir is not harmful to residents, despite the smell that has caused much resident concern. In a letter dated Wednesday, the district said that “based on the results of [...]
Detailed work by water district to resolve foul odor issue
As the Santa Margarita Water District continues to work to quell the foul odor in town caused by an algae bloom in the district’s Upper Oso Reservoir, district officials have provided the City with a chronology of events to date and an update of efforts to restore the condition of the reservoir: Thursday, October 29: [...]
City will stop irrigating with recycled water, again
The City will once again temporarily stop irrigating with recycled water in an effort to help quell the foul odor caused by an algae bloom in the Santa Margarita Water District’s Upper Oso Reservoir. The City’s move comes as the water district continues to work to eliminate the odor that has prompted much resident concern. [...]
Letter from Santa Margarita Water District General Manager to MV Residents
Dear Resident: As you undoubtedly know, due to an algae bloom in the Upper Oso Reservoir, nearby neighborhoods have experienced odors this past week. Algae blooms are a natural phenomenon but their frequency, duration and intensity can vary due to several factors, including sunlight, weather and water temperatures, and nutrients in the water… Read thefull [...]
City to stop irrigating with recycled water through Thursday
The City will temporarily stop irrigating with recycled water in an effort to help quell the foul odor caused by an algae bloom in the Santa Margarita Water District’s Upper Oso Reservoir. The City’s move comes as the water district is working to eliminate the odor that has prompted much resident concern. District officials say [...]
Water district says foul smell from algae bloom is temporary
Santa Margarita Water District officials say the foul smell caused by an algae bloom in the district’s Upper Oso Reservoir is expected to subside within the next several days. The water district has added equipment in the lake to help return the oxygen levels to normal. As of Saturday, the dissolved oxygen levels have started [...]


