Laguna Niguel Lake, Southern California, US

Laguna Niguel Lake is 13 ha reservoir used for recreation and fishing.

A total of 51 tonnes of Phoslock was applied to Laguna Niguel Lake in Southern California in April 2013. Prior to the treatment, the reservoir had issues with poor water quality, foul odours, a declining fishery and an outbreak of avian botulism, which promoted the need for restoration measures. Water chemistry, benthic macroinvertebrate and sediment sampling was undertaken pre- and post- Phoslock application. 

Phoslock significantly decreased and sustained lower concentrations of phosphorus in the water column (total phosphorus decreased by > 80% and free reactive phosphorus decreased by > 95%). The application also shifted sediment phosphorus fractions to highly stable forms, compared to pre-treatment concentrations. The monitoring also documented no significant composition or diversity alteration to the benthic macroinvertebrate community after the Phoslock application. 

For a summary document and detailed results of the application, please follow the link in the 'Downloads' section below.