Algae Blooms in Our Waterways: 3 Tips for Prevention

By Carrie Jensen on behalf of One Truckee River
Funding provided by the Western Regional Water Commission

Algae Blooms Increasing Across the US and Eastern Sierra

As late summer approaches, you might notice more news popping up about toxic algae blooms. From Washington to Utah to Vermont, algae blooms were all over the news last summer and this summer’s drought conditions could lead to prime conditions again this year. 
Waters across the U.S. are seeing higher incidents of algae blooms, and the Eastern Sierra is no exception. Down south, we saw algae blooms in Crowley Lake near Bishop and Bridgeport Reservoir. In the north, the Truckee River watershed had algae blooms at Virginia Lake in Reno and at Pyramid Lake. These algae blooms prompted local water quality officials and health departments to issue warnings to avoid swimming and recreating in these waterways due to health risks.

Photo Credit: Carrie Jensen Caption: Algae accumulates on the shores of Virginia Lake in Reno, Nevada on Sept. 15, 2021.

So What Are Algae?

Algae are a large group of photosynthetic organisms that live in water. While they are normal and common in waterways, they can cause water quality problems when they grow out of control and form large populations.

Photo Credit: Carrie Jensen Caption: Algae forms thick mats in a pond.

What causes algae blooms?

Algae blooms occur when conditions are prime for their growth. Algae are fond of warm waters with lots of sunshine and nutrients. These conditions usually occur in the summer or early fall, and they are especially prime when runoff in the watershed supplies excess nutrients.

While algae blooms have historically been pretty rare in the Eastern Sierras, decreased fresh water flows from reduced snowpack, increases in summer temperatures, and inputs of nutrients from urban runoff could be contributing to algae bloom increases.

Urban runoff is water that washes across our landscapes and streets and flows untreated down the storm drains and out to local waterways. It can carry excess nutrients from fertilizers we use on our lawn or landscapes. If applied in excess, these fertilizers can easily wash off when we turn on sprinklers and then flow down the storm drain.

Photo Credit: Carrie Jensen Caption: Urban runoff from sprinklers flows off a landscape and into the storm drain.

Why is algae so bad?

Algae blooms have detrimental effects for aquatic life and also for people and pets that play in the water. Algae blooms can decrease the amount of oxygen available in the water for fish and other aquatic life. Without enough oxygen, fish can die off.  Algae blooms can also produce toxins that are harmful and even lethal to people and pets.

Photo Credit: Dr. Jennifer L. Graham, U.S. Geological Survey Caption: Pictured here is Binder Lake in Iowa covered in algal blooms. One of the effects algal blooms can have is fish kills in areas where oxygen is depleted or when algal blooms are producing toxins.

What can we do?

The good news is that we can help prevent algae blooms! While we may not have the personal power to increase snowpacks or dictate summer temperatures, we do have the ability to reduce nutrients, like nitrogen and phosphorus, that flow into our waterways. 

One Truckee River has a few River-Friendly Yards tips to help you reduce nutrients that flow off your yards and driveways.

Tip #1: Use the carwash

Soaps used for car washing usually contain phosphates. When you wash your car in the driveway, these nutrients can wash off down the storm drain and contribute to algae blooms in waterways. If you wash your car at the carwash, the wastewater is sent to the sewer treatment plant where those phosphates are removed.

Photo Credit: Paul Brennan from Pixabay Caption: Commercial car washes are required to send their waste water to the sewer treatment plant.

Tip #2: Use fertilizers responsibly

Fertilizers used in our gardens are great because they help our plants grow, but if they wash off that’s money down the drain and bad news for local water quality. To save money and protect our local waterways from excess nutrients, be sure to follow the instructions and only apply the amount needed. In this case, more isn’t better!

Tip #3: Install a buffer strip

When lawns are installed next to sidewalks, it’s really easy for water from sprinklers to runoff and carry nutrients from fertilizers down the storm drain. We can avoid this if we move our lawns away from the sidewalk. Instead install a buffer strip of waterwise plants with drip irrigation between the lawn and the sidewalk.

Photo Credit: Carrie Jensen Caption: Buffer strips are plantings of water-wise plants placed between the lawn and sidewalk. They help reduce overspray and runoff from sprinklers and add seasonal interest to your garden.

Need help with the irrigation upgrades? Contact a QWEL Professional in your area. These landscape professionals are experts in efficient irrigation design for high desert landscapes.