Wildfires Could Impact Southern California Water Quality
How do wildfires affect water quality? Anytime there is an ecological disaster, your San Diego water supply could be at risk. Wildfires are no exception. The record-setting 2017 California Wildfires were some of the most destructive the state has ever seen.
Winter and spring rain exacerbate the issue, slowing down cleanup and causing toxic particles to runoff into streams and reservoirs.
Water Sources from Northern California
According to the U.S. Department of Agriculture, about half the water supply in the southwestern U.S. is supplied by water from forests, which usually yield higher quality water than other sources. approximately 80 percent of the freshwater resources in the U.S. originate in forested land, and more than 3,400 public drinking water systems are located in watersheds containing national forest lands.
Though Southern California is not directly affected by the forest fire outbreak, many area water sources come from northern parts of the state. The State Water Project redistributes water from rivers in Northern California through power plants, pumping stations and aqueducts. 70% of SWP water is used for the San Francisco and Southern California areas.
Other sources for Southern California water include the Los Angeles Aqueduct from the Sierra Nevada Mountains, the Colorado River watershed and local sources, such as recycling and groundwater.
Influence of Wildfire on Local Watersheds
Water quality can be compromised years after a wildfire has burned. During the actual event, ash can fall on lakes and reservoirs that are important to drinking water supplies. The largest issue, however, is the tendency of watersheds to be more susceptible to flooding and erosion. Other ways California wildfires can affect local watersheds include:
- Changes of amount and timing of snowmelt runoff, changing the filling of reservoirs.
- Increased sediment in reservoirs, leading to shortened lifetime and increased costs. This includes nutrients, dissolved organic carbon, ions and metals.
- Transport of sediment and debris downstream to water treatment plants.
- Increased turbidity (cloudiness), and increased amounts of iron and manganese, increasing chemical treatment requirements and other changes in chemistry that can alter drinking water treatment.
From added ash and soot in the ecosystem to fire retardant chemicals and changes in the behavior of snowpack, California wildfires can — and will — have an increasingly noticeable impact on water quality.
Roughly 70% of all Californians’ water comes from the mountains (the Sierra Nevada), where fires can impact the water supply there as well as downstream, especially as the frequency and intensity of wildfires increases. For example, if fires burn hot enough and near enough to the mountains, the increased heat can change the rate and intensity of snowmelt, which increases runoff. Wildfires can also increase the amount of water contaminants, by making it easier for ash and other fire debris to find its way into the water supply when snow runoff is accelerated.
Water Quality After Wildfires
Scientists are studying just how much wildfire impacts the water supply, and the overall hydrological cycle in impacted areas. It’s evident already that wildfires, especially frequent ones, can impact not only snow pack but also water table levels and surface water availability.
This most noticeable effects on California water quality after wildfires are typically changes in the taste, color, appearance, and/or smell of drinking water in areas with impacted watersheds. So if you live in an area near the Russian River delta, for example, which has been drastically transformed by the Santa Rosa fires, it’s likely you’ll have seen a change in the quality of your tap water. These changes can also be seen in areas of Los Angeles and Northern California where large-scale fires have consumed huge quantities of land.
Wildfire’s Short And Long Term Impacts On California’s Water
Understanding how frequent and intense wildfires affect the ecosystem and the water supply in the long term is still a work in progress. As more data becomes available, scientists expect to learn more about how water quality and availability will be affected when wildfires hit. There are few changes we can expect with confidence however. Most notably, these will include an increase in cost associated with water filtration and treatment — since wildfire debris can lead to a myriad of issues with water quality, and local communities will be left footing the bill to treat water that increasingly has issues like turbidity (cloudiness), chemical contamination from fire retardants, microbial contamination from algae as a result of added water debris, among others.
In addition to water treatment issues, wildfires may cause long term structural challenges for California communities. Imagine large downed, charred trees and forest debris sweeping along waterways toward dams and accumulating in reservoirs. This strains the existing water infrastructure and increases the chances that additional contaminants will enter the system. As a result, it’s likely that communities will need to invest more heavily in their water treatment systems and consider replacing and retrofitting components of the water storage and distribution infrastructure.
Protect Yourself from Fire-Contaminated Water
The reality is that living in California will increasingly include challenges associated with wildfire-affected water quality. Whether you notice strange tastes or unpleasant odors after a fire, or the water becomes cloudy or has a different appearance, chances are your tap water will be impacted at one time or another.
In addition to aesthetic issues with water, fires can increase the likelihood that water could be contaminated with more serious issues that can be difficult to detect – like fire retardant chemicals which can be dangerous for consumption.
One of the best steps you can take is to be proactive about your own water quality at home. An in-home water filter or drinking water treatment system — like our Aqua-Cleer® series drinking water systems — can protect your water at the source, so you can feel confident that the water you’re drinking is always safe and great tasting.