If you've been following the Silverlake Reservoir refilling saga, you may have also noticed a mysterious pile of huge white bags at the adjacent Ivanhoe Reservoir. The DWP's Marty Adams tells John what's inside...

The Ivanhoe Reservoir, c. 1935. From the L.A. Public Library photo archive: 'View looking east towards the Ivanhoe Rservoir, near the intersection of Tesla and W. Silver Lake Drive. The black structure shown over the reservoir is a cover made of wood and black roofing material.'
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Courtesy L.A. Public Library
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