By Dianne Feinstein and Joanne Marchetta

Twenty-one years ago, President Bill Clinton came to Lake Tahoe to announce a major environmental restoration effort. That first Lake Tahoe Summit launched an unprecedented public-private partnership that has since invested more than $2 billion to save the lake.

Over two decades, through the environmental improvement program, the Tahoe partnership has created one of the nation’s most ambitious and successful environmental restoration and conservation programs. In fact, according to Lake Tahoe scientists, had this partnership not formed, lake clarity could be nearly 20 feet worse than it is today. 

While the lake and its forests are healthier now from this work, we must double-down on our effort in the face of threats from climate change.

Earlier this month, the Tahoe Environmental Research Center at UC Davis released its annual report on the state of Lake Tahoe. The report is a clarion call-to-action for all who love this lake.

While the report makes it clear our investments are having a positive effect, climate change is having a profound impact on the Lake Tahoe Basin. Climate change is also making the existing challenges in the Tahoe basin harder to address.

One of the most notable effects of climate change is the rising temperature of the lake. Surface temperatures are rising at half a degree each year—14 times faster than the historical average. We know that rising temperatures make it easier for algae to grow.

Partners around Tahoe are reducing stormwater pollution that harms lake clarity and helps fuel algae growth. Over the last five years, we have reduced clarity-harming fine sediment pollution by 12 percent, and reduced phosphorus and nitrogen pollution, nutrients that spur algae growth, by 8.5 percent and 6 percent, respectively.

That’s more than 268,500 pounds of fine sediment that is no longer washing into the lake each year. This important work to protect and restore Lake Tahoe’s clarity and keep Tahoe blue must not only continue, it must accelerate to protect the lake’s water quality from climate change.      

The problems aren’t only in the water. Lake Tahoe is experiencing longer summer seasons, affecting the delicate ecosystems around the lake. The hot summer season has increased by 26 days over the last 50 years.

Longer, hotter summers and more severe droughts are killing trees around the lake at an alarming rate. The U.S. Forest Service estimates there are 136,000 dead trees in the Tahoe basin. While we’ve made progress thinning forests and removing the overabundance of fuel for forest fires, drought and climate change continue to stress Tahoe’s forests. We must do more to improve the health and resilience of Tahoe’s forests and prepare our communities for wildfire.       

Climate change is happening now, and we must act.

Facing a seemingly impossible challenge 20 years ago, this community came together to save the lake. We believe we can again.

Of course, addressing climate change will require a global effort. But with all our success over the last two decades, the world already looks to Lake Tahoe as proof that environmental change for the better is possible. This is our opportunity to continue to lead on an international stage.

We must keep working together to solve the problems of climate change—not just globally but right here in Lake Tahoe. We must strike at the heart of the issues detrimental to the lake.

This is going to require continued and increased focus on forest management and wildfire preparedness, the control—if not eradication—of invasive species, and finding more ways of reducing the amount of nutrients flowing into the lake. 

Transportation is another key issue we must address. Car emissions threaten air and water quality. We can reduce that traffic by expanding public transportation and biking options.

Just like two decades ago, the federal government is ready to help with those efforts. Last year, we passed the Lake Tahoe Restoration Act, which reauthorizes $415 million of federal funding over the next seven years to fund programs vital to the lake’s health.

This is an important commitment, but only one piece of the puzzle. Tomorrow, we will hold the 21st Lake Tahoe Summit at the Tallac Historic Site on the South Shore. All four senators from California and Nevada will be joined by supporters of the lake from the public and private sector, including representatives from the federal, state and local levels of government. Our keynote address will be delivered by former Secretary of the Interior Bruce Babbitt, who served under Clinton during the first summit.

The summit will be a chance to celebrate all we’ve accomplished to restore Lake Tahoe. It will also be a chance for the public-private partnership formed 20 years ago to re-commit its efforts towards solving the problems created by climate change.

Tahoe is ready to meet this new challenge. We hope you will join us.

Dianne Feinstein is a Democratic senator from California and Joanne Marchetta is executive director of the Tahoe Regional Planning Agency.