In 2022, the contiguous U.S. experienced concerning stretches of drought. For us in the West, the state of Utah included, peak drought coverage reached 91.3% of the region. 2023 brought slight reprieve to areas of the country with higher than average levels of precipitation, like we experienced in Utah (the ’22-’23 ski season was awesome), but Northern and Southern regions of the country experienced record-breaking heat and dryness. Overall, Summer 2023 was the warmest on record in North America and it looks like we have another warm, dry Summer ahead in 2024. We’re all taking steps to do our part to conserve water and many are wondering… would cutting down trees help us save water?
Our answer won’t be surprising. No, cutting down trees will not help save water. Slowing down with our tree plantings won’t help save water either. Since 1988, we’ve organized community tree planting events throughout the state of Utah in an effort to increase our urban forests, bring trees to communities that have been historically marginalized, and bring communities together. We plant trees with our changing climate in mind, knowing the benefits trees provide will aid our community for generations, especially with an increasingly dry climate.
As, Ben Abbott, a Professor of Ecosystem Ecology at BYU, said when asked about this issue, “The trees aren't just straws that are consuming water. They also are shading the ground, so they're reducing the amount of sunlight that's hitting the snowpack, so that can extend the length of time that we have snow on the ground.”
By slowing the snowmelt, water is gradually introduced to our water supply rather than evaporating or surface runoff. We are also only able to store so much water, so we need the snow to melt slowly in order to create a steady supply of water, both for our reservoirs and natural waterways.
Abbott continued, “If you get into a relatively dry environment like we have here in Utah… you can have no increase, or even a decrease in water, when you remove those trees.”
Once trees are established, their water needs are modest. Mature trees will absorb between 10 - 150 gallons of water per day, but trees only retain a maximum of 5% of that water for plant growth. This means 95% of the water “consumed” by trees is released back into the environment.
Trees are key for saving water and preventing water pollution. Their interception of rainwater and subsequent filtering, transpiration, and groundwater charge make trees a vital part of the water cycle.
Tree roots filter pollutants from storm runoff that would otherwise end up in lakes, rivers, and streams. Around 180 million people in the U.S. rely on forests to filter their drinking water and Utah is among them. The majority of our drinking water comes from precipitation, snow in our mountains that melts and filters through our forested mountains before making its way to our homes. The same work is done by trees in urban areas. Trees capture water, filter it, and release it back into the water supply, which sustains our communities and our state’s iconic natural features, like the Great Salt Lake.
Trees are also essential in preserving soil quality and flood prevention. Their deep roots hold soil in place, preventing erosion. They also absorb and store rainwater, reducing runoff and sediment deposit after storms. By preventing erosion and storing rainwater, trees reduce flood risk. Flooding is Utah’s most common and destructive natural hazard, making the flood-mitigating benefits of trees invaluable. Healthy soil is also essential in preserving our groundwater supply, which feeds our tributaries and the Great Salt Lake itself. Without healthy soil, a great percentage of the water that comes to Utah in the form of precipitation would evaporate before making it to our waterways, significantly cutting the volume of water that makes it to our homes and to the lake.
In addition to preventing floods and aiding water management, trees enhance air quality, reduce the urban heat island effect, reduce energy consumption, and make our communities more comfortable, safer places to live. It’s worth noting that cities and towns in Utah use only 9% of our available water supply. This includes water used for the maintenance of trees. We all want to do our part in easing drought conditions and increasing the amount of water that makes it to our beautifully unique Great Salt Lake, but the answer is not to cut down trees. In fact, having more trees will do more to increase the efficacy of the regional water cycle, ensuring a healthy supply of water both for us, regional wildlife, and the lake.
