By Kathryn Reed

The quality of roads in the basin and Lake Tahoe’s clarity may be more closely tied together than previously believed.

That is the belief of El Dorado County officials.

On the day the Lahontan Regional Water Quality Control Board voted to approve the next five-year Lake Tahoe municipal storm water permit for South Lake Tahoe, El Dorado County and Placer County, there was talk of looking at new ways to curb the sediment load.

“There is some new information we have showing roads contribute upward of 30 percent of the sediment into the Lake,” Russ Wigart with El Dorado County told the state agency.

The county does a significant amount of in-house research. The plan is to study the relationship between the pavement index condition and runoff. The pavement index condition goes from 0-100, with 100 being the best. Tahoe’s roads are anything but the best.

“Our roads this year were completely annihilated,” Wigart said. Winter weather has made some still impassable.

The plan is to study different surfaces to see what might be best for Tahoe.

While this is actually the 25th anniversary of the Lake Tahoe storm water permit program, the current iteration with the credit system just completed its first five-year cycle, which also incorporated the total maximum daily load requirements.

The atmosphere at the March 9 meeting was 180 degrees different than in December 2011. At that meeting the hostility was palpable between the jurisdictions and Lahontan. All five El Dorado County supervisors stood at the podium to denounce the plans.

At Thursday’s meeting the jurisdictions and Lahontan had praise for each other. While the jurisdictions still believe money will be an issue to accomplish the goals and that they are not easy measures to meet, they believe in the cause.

Despite the animosity at the start, all three locales met their goals. South Lake Tahoe needed 190 credits and achieved 209, El Dorado County needed 163 and hit 164, and Placer County needed 260 and earned 277. These credits equate to a 10 percent sediment reduction from the 2003-04 base year.

One credit is equal to 1.0 x 10 to the 16th fine sediment particles with a diameter smaller than 16 micrometers.

This permit that was just approved mandates another 15 percent reduction.

According to Lahontan’s staff report, “To achieve the transparency standard, estimated fine sediment particle, phosphorus, and nitrogen loads must be reduced by 65 percent, 35 percent, and 10 percent, respectively. Given the magnitude of the needed load reductions and the current available understanding of load reduction options, achieving the load reductions needed to meet the transparency standard is expected to take 65 years. A 20-year interim transparency goal, known as the Clarity Challenge, requires basinwide pollutant load reductions to be achieved within 15 years, followed by five years of monitoring to confirm that 24 meters of Secchi depth transparency has been reached. Implementation efforts must reduce basinwide fine sediment particle, phosphorus, and nitrogen loads by 32 percent, 14 percent, and 4 percent, respectively, to achieve this goal.”