Algal Control By Phosphate Restriction

Mason Lake (Irvine) contains toxic algae. They will install a water treatment plant to remove phosphate.

Newport Back Bay is nearby and may also be contaminated with the toxic algae.

Eastlake (Yorba Linda) is the control lake and is not being treated.

Mason Lake

Sampling Site

Toxic Algae in Mason Lake

Visibility: 4cm

High phosphate levels are from many water fowl

Toxin-Producing Microcystis sp.

Mason Lake: One Mile From Newport Back Bay Estuary

Newport Back Bay

Urban runoff into the bay

Bay

Storm drains with Phosphate-rich water from urban run-off

Phosphate-rich water dumping into the Bay

Upper Newport Bay

Top birding site Home to 200 species of birds 30,000 migrating birds per day Audubon Society/F&G conducts a

monthly bird count

Endangered Species at Newport Back Bay: California Least Tern

Light-Footed Clapper Rail

Brown Pelican

Peregrine Falcon

Belding’s Savannah Sparrow

Coastal California Gnatcatcher

East Lake (Yorba Linda)Sampling Site

East Lake: Yorba Linda, CA

Algae is creating a foamy surface scum

A Diatom called Navicula is causing the foam

Sample Analysis

Algal Assay Species ID Cell count

Chlorophyll Assay Flow Cytometry

Species populations Phosphate Assay

Algal Assay

Eastlake: Diatoms

Mason Lake: Cyanobacteria

Flow Cytometry is used to count algal cells and separate them by species

Flow Cytometry is used to count algal cells and separate them by species

Chlorophyll Assay

Filter the water to capture the algae on the filter paper

Mason Lake Eastlake

Grind up filter paper with acetone to release chlorophyll

After Centrifuge

Filter algae out of water, add a reagent that turns blue when it contacts phosphate

Phosphate Assay

Mason Lake Eastlake

Filters with algae left on them

The deeper the blue color, the

more phosphate is present.

A dilution series with phosphate standard