By Associated Press

With all their modern scientific equipment and state-of-the-art computer models, researchers trying to better understand the effect of algae growth in Lake Tahoe are searching for new tools to aid in their mission — old photo albums.

Experts at the UC Davis Tahoe Environmental Research Center want to better understand the trend in long-term algae growth.

“Everyone wants to know if there’s more of this stuff, but we don’t know,” said Geoff Schladow, a professor of water resources and environmental engineering at UC Davis.

Researchers study algae growth because it is linked to high levels of nutrients, which enter the lake atmospherically and through stormwater runoff. Fertilizer, for example, contains nutrients and can find its way into the lake when it rains, thus contributing to algae growth.

Despite a reduction in the amount of sediment entering the lake last year because of the ongoing drought in the West, the concentration of nitrate is actually higher.

The problem is scientists don’t have much historical data about algae.

“What we’re left to use is anecdotal data,” Schladow said. “We also ask for old photos, so if anyone has some they’d like to share, unfortunately that is the only older data we have.”

Scott Hackley, a staff research associate at UC Davis, said he’s worked with archivists at UNR to find old photos, but he and his team are hopeful that the community can help as well.

“It’d be nice to get some old photos with the year, time of year and the location to fill in some of the historical gaps,” he said.