Our Invisible but Critical Water Source

You can’t see them. You can’t swim in them. But groundwater aquifers are one of the most important sources of water in the North Coast. Aquifers are water-rich underground areas. They aren’t like lakes or pools but are composed of water-filled areas between rocks, sands, and gravels.

Plants and animals benefit from groundwater when it’s near the surface, and feeds creeks and streams. Humans tap into aquifers through wells used for drinking, irrigating crops and operating businesses. People who live in rural areas rely almost exclusively on groundwater, and while cities in Sonoma and Mendocino counties get most of their water from the Russian River, groundwater provides a critical back-up source that is used during droughts or in emergencies.

In some parts of California, like the Central Valley, aquifers are large, continuous and relatively close to the Earth’s surface.  But aquifers in coastal counties are much more complex. Separated by mountains, hills and geologic features, including earthquake faults, there are 14 identified groundwater basins in Sonoma County and six basins in Mendocino County. This geologic complexity explains why one landowner can have a productive 50-foot deep well, while their neighbor’s 200-foot deep well provides only a trickle of water.

Studies conducted by the US Geological Survey (USGS) found that water in some of the deeper local aquifers has been underground for more than 20,000 years while water levels in aquifers closer to the surface can fluctuate seasonally, dropping during the summer when pumping is heavier and increasing during the rainy season.

Unfortunately, too many wells, too much pumping, and droughts can temporarily – and in some cases permanently – impact aquifers, resulting in dry wells, poor water quality, depleted creeks, and in some cases sinking of the land surface. In areas close to the ocean and bays (like Southern Sonoma Valley), the loss of groundwater can result in salt water migrating into groundwater basins.

Some communities in the Central Valley where groundwater has been over-pumped have seen the land surface drop by 30 feet, damaging roads, canals and bridges. Declining groundwater levels and polluted run-off from past agricultural practices have also degraded water quality in several Central Valley communities, resulting in residents having to use bottled water for drinking and bathing.

These problems were the motivation for the Sustainable Groundwater Management Act (SGMA), which became California law in 2015.  To make sure that people fairly share and wisely use and protect this shared resource, SGMA requires communities to manage groundwater by, first, creating new Groundwater Sustainability Agencies (GSAs). In Sonoma and Mendocino counties, GSAs were created for the Santa Rosa Plain and Petaluma, Sonoma and Ukiah valleys.

The second step of SGMA is to gain a scientific, quantifiable understanding of current and future problems, and to develop solutions through the creation of a Groundwater Sustainability Plan (GSP).  The third step of SGMA is to implement the GSP and obtain sustainable conditions over a 20-year time period, with check-ins every five years. If local communities fail in taking any one these steps, the state can take over management of the basin. So far, local GSAs are on track and are working on the GSPs.

SGMA requires that the GSPs be developed through a transparent process with public input and community engagement. The GSAs all hold regularly scheduled public meetings, and materials are available for review.

How local well owners will be affected by SGMA will depend on the problems (and solutions) identified in the GSPs. One thing is certain:  SGMA prohibits the GSAs from requiring residential groundwater users to install meters on their wells. In regard to costs, if aquifers are healthy and there are minimal concerns about future impacts, the GSP could simply require ongoing monitoring and reporting of groundwater levels through test wells and voluntary programs. If problems are identified, the GSP could identify potentially more costly programs (like water conservation) or projects (like recharging the aquifers) to ensure that groundwater is sustainable. In some areas with severe problems, the GSA may be required to limit groundwater use.

Locally, the four GSAs each received a grant of one million dollars to help prepare the GSPs. If more funding is needed, SGMA allows groundwater users to be charged for the costs of running the GSA and developing and implementing the GSP. The Santa Rosa Plain GSA (encompassing the general valley floor area from Cotati to Windsor and from the foot of Sonoma Mountain to Sebastopol) is currently looking at a possible groundwater sustainability fee to cover costs (up to $13 a year for rural residential well owners and up to $26 per acre-foot for other groundwater users). The Santa Rosa Plain GSA will be holding a series of community meetings on March 4, 6 and 7. For more information on the Santa Rosa Plain fee, go to www.santarosaplaingroundwater.org/finances/fee.

This article was authored by Ann DuBay, Sonoma County Water Agency, on behalf of RRWA. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, habitat restoration, and watershed enhancement.

Russian River-Friendly Landscaping Guidelines

Every landscape can have a beneficial impact on the Russian River and the surrounding environment. In 2010, the Russian River Watershed Association (RRWA) created a comprehensive toolbox of principles and practices to provide landscape professionals in the region with guidelines for protecting our environment, known as the Russian River-Friendly Landscape Guidelines (RRFLG):

  1. Landscape Locally
  2. Landscape for Less to the Landfill
  3. Nurture the Soil
  4. Conserve Water
  5. Conserve Energy
  6. Protect Water and Air Quality
  7. Create and Protect Wildlife Habitat

While these guidelines were created for landscape professionals, residents can also find insight on how to apply the guidelines through RRWA’s online resources for residential landscaping: www.rrwatershed.org/project/rrflg. RRWA encourages watershed residents to consult with a Bay-Friendly Qualified Professional for design and management of home landscapes using ReScape’s directory: https://rescapeca.org/directory.

As part of RRWA’s Russian River-Friendly Landscaping program, RRWA hosts biennial events for professionals to provide further education on the RRFLG. The 5th Biannual Russian River-Friendly Landscaping Event “Planting Resilience: Stories, Science, and Strategies,” will take place in Santa Rosa on Wednesday, February 6, 2019. The event will cover restoring, replanting, and regrowing Russian River watershed landscapes after the October fires. The keynote speaker is Douglas Kent, author of several titles including Firescaping and Ocean Friendly Gardens. Other speakers include Chris Grabil, Steve Quarles (UC Berkeley), Kristin Maharg Suarez (Community Soil Foundation), Scott Sherman (ReScape), and Veronica Bowers (Native Song Bird Care). The event will also include a panel discussion on the landscape design templates for the fire rebuild, developed by Sonoma‑Marin Saving Water Partnership.

Sonoma-Marin Saving Water Partnership Landscape Design Templates for Fire Rebuild

The Sonoma-Marin Saving Water Partnership has developed eight scalable landscape design templates for the fire rebuild. These free, front yard designs are scalable to fit landscaped areas up to 2,500 square feet, ready‑to‑permit, and in compliance with local Water Efficient Landscape Ordinances.

The templates include conceptual plans that illustrate the interconnectedness of back and side yards with the front yard, as well as optional features such as rain water catchment, graywater systems, rain gardens, and  swales. Preparations for optional features such as stubbing out a line for greywater or grading yards for rain gardens and swales can be done for little or no additional cost during a rebuild.

For more information:


This article was co-authored by Chris Grabill, Watershed Task Force, and Christina Leung, RRWA staff. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, habitat restoration, and watershed enhancement.

The Plant Invasion

Give them an inch and they’ll take an acre…as the California Invasive Pest Council says. There are a whopping 195 invasive plant species in Sonoma County. In the northwestern forest region which includes Mendocino County, 265 invasive species have been identified. An invasive plant species is non-native and aggressively out-competes native species! In other words, they spread fast and crowd out other plants, harming ecosystems and impacting water quality. Native plants provide shelter and food for native insects, birds, and animals. Invasive species tend not to have habitat value. In fact, they sometimes destroy the very habitats native species need to survive.

Ludwigia hexapetala (Water Primrose)

One of the most damaging invasive plants is invasive Ludwigia or water primrose. Water primrose is a lovely, floating plant with delicate yellow flowers and is a favorite for artificial ponds and aquariums. Unfortunately, several subspecies of water primrose (Ludwigia hexapetala and Ludwigia peploides) are aggressively invasive and among the most concerning of the invasive species for water quality and stream health. Invasive Ludwigia grows quickly and thickly on water surfaces, blocking out light, using up the oxygen and choking out other life. When invasive Ludwigia covers a water body surface, aquatic birds cannot penetrate the thick mat of Ludwigia with their beaks to hunt for food. Ludwigia also depletes the oxygen in the water body it covers, so that the oxygen is no longer available for fish and other life.

Arundo donax (Giant Reed)

Arundo donax (Giant Reed) grows best along streambanks. It was introduced for erosion control because it quickly covers exposed soil. Unfortunately, that very quality that is useful for erosion control, makes it an invasive species, crowding out native plant species, and reducing habitat value for birds and other animals. Arundo has another huge drawback – it is highly flammable, speeding the spread of wildfire.

Protect our river. Protect our streams. Don’t plant or spread invasive species. Here is what you can do…

  • Plant California native plants in your yards and gardens. Native plants can be just as beautiful as exotic ornamentals and provide ecosystem benefits. For example, the California Lilac has lovely purple blooms, It’s a nitrogen-fixing plant. The California Fuchsia blooms deep red or purple and attracts hummingbirds. The California Native Plant Society has an on-line tool to help you select native species. www.cnps.org/gardening. The California Invasive Plant Council also lists helpful links for plants to use and stay away from for land managers, landscapers and for the public www.cal-ipc.org.
  • Don’t plant a pest in your pond. If you have a pond, please get help from a native plant expert to purchase local, native species, not invasive ones. Just because you can buy it legally, doesn’t mean it’s not invasive. Go to the California Native Plant Society on-line tool www.cnps.org/gardening or ask your local nursery for help.
  • Clean your boat. One of the ways invasive plants travel from one water body to another is by hitching rides on boats. If your boat has been outside of our region, clean the exterior of your boat thoroughly before re-entering the Russian River or any of our lakes or ponds. Remove any plant materials off your boat, even very small pieces.
This article was authored by Cristina Goulart, for the Town of Windsor, on behalf of RRWA. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, habitat restoration, and watershed enhancement.

10 Tips for a Sustainable Holiday Season!

From Thanksgiving to New Year’s Day, household waste increases by more than 25%! Increased food waste, shopping bags, gift packaging, wrapping paper, bows and ribbons add an additional 1 million tons a week to our landfills. It doesn’t have to be this way. Make your holiday season as sustainable as possible by incorporating these 10 waste reduction tips:

  1. Buy recycled-content paper products for traditional gift wrapping or holiday cards.
  2. Avoid traditional wrapping in favor of materials that you already have around the house like newspaper, sheet music or old maps. You can also use scarves, t-shirts or other wrapping that could be a gift as well.
  3. Cook smarter this holiday season and reduce food scraps by cooking only what you and your guests can reasonably eat. Food is the number one thing in America’s landfills. Check out the “Guest-imator” tool to help you figure out the right amount of food to prepare: www.savethefood.com/guestimator/guests.
  4. Recycle clean aluminum pie and turkey tins; cardboard boxes; cracker boxes; glass food jars; metal cans; paper egg cartons; plastic juice bottles; plastic milk and water jugs; soda, cider, wine, champagne and beer bottles. If you’re not sure if an item can be recycled contact your local solid waste department.
  5. Reduce waste by giving experiences rather than stuff like gift certificates and e-tickets to plays, movies, concerts or sporting events.
  6. Utilize electronic holiday greeting cards, offered through a variety of websites, for a convenient, no-cost, waste-free alternative.
  7. Just say no to the frosted Christmas tree. Many cities and counties offer Christmas tree recycling. However, if you opt for a flocked tree, most often these cannot be recycled because of the chemical content used to give the tree that frosted look. Go au natural or opt for an artificial tree that can be reused year after year.
  8. Incorporate recycling dead batteries into a holiday shopping trip. Many retailers offer in-store collection. Find a drop-off location near you by visiting www.call2recycle.org/locator.
  9. Put all your lights on timers for energy savings and peace of mind while you’re away.
  10. Never pour cooking fats, oils, and grease down the drain. If you pour them down your sink drain, they will harden in your pipes and may block the flow of sewage away your home! The best way to deal with fats, oils, and grease from cooking waste is to let them cool then scrape into the trash.

For more information on consumer recycling and waste reduction tips go to:

Mendocino County: Mendorecycle.org or call the Recycling Hotline at (707) 468‐9710.
Sonoma County: Recyclenow.org or call the Sonoma County Eco‐Desk at 565‐DESK (3375).

This article was authored by Sarah Dukett, of the County of Mendocino, on behalf of RRWA. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, habitat restoration, and watershed enhancement.

Are You Rain Ready?

It’s autumn and time to prepare for the rainy season and winter. This time of year, is when we are thinking about raking up leaves, cleaning out rain-gutters, and undertaking some car maintenance like replacing wiper blades and changing the anti-freeze. But did you know you can also help protect our local creeks, communities and environment? With the coming rains, anything we spill, drop, throw, or store on the ground can be washed off by storm water and directly enters a creek or river, without treatment, having a toxic effect on fish and wildlife and people. Polluted runoff can come from a variety of sources – oil and grease from pavement; trash and pet waste from our yards or parks; fertilizers and pesticides from lawns or gardens; sediment from construction activities; and improperly stored loose materials like garden mulch or topsoil.

A good rule of thumb to remember is “Only rain down the storm drain” as almost everything else can become a pollutant and it is unlawful to put anything into the storm drains but storm water. Below are some ways that you can be rain ready and help reduce pollution in our waterways. It costs less to prevent pollution and flooding than to clean up the creeks or neighborhoods.  Let’s all do our part!

Rain Ready Solutions

  • Dispose of pet waste in a trash container.
  • Pick up leaf litter and yard clippings around your home to compost or put in your yard waste container.
  • Sweep up your driveways and sidewalks rather than hose them down into the street gutter. “Sweep Up the Street Gutter” in front of your residence placing the trash and yard waste into the correct bins.
  • If you store garden products (soil, mulch, or compost), gas-powered garden equipment, or chemicals such as pesticides, herbicides, and fertilizer, make sure they are securely covered, and avoid applying chemicals if rain is in the forecast.
  • Turn down your irrigation system run times during the dry fall months and turn your system off once the rains begin. Even during dry periods of the winter months, plants need little or no water.
  • Use a commercial car wash, which recycles water and keeps soapy water out of the storm drain. If you wash your car at home, do it on a lawn and dispose of buckets of soapy and rinse water in the sink.
  • Clean out your pickup truck bed, and secure items hauled in or on top of your vehicle. Random trash left in the back of your pickup can easily blow out onto the street and end up in the creek.
  • Fix all car leaks. Oil, antifreeze and other harmful chemicals can drip onto streets, parking lots and driveways and then wash off into creeks. These products should only be disposed of at a household hazardous waste collection facility. For Sonoma County residents, see recyclenow.org or call the Sonoma County Eco Desk (707 565-DESK (3375)). For Mendocino residents, see www.mendorecycle.org or call (707) 468-9704 for more information.

Another area of major concern for the next several years is the number of vacant lots or those under construction in burn areas. Sediment is a pollutant in our creeks as much as the other examples listed in this article. The property owners and contractors are responsible to protect their lots to prevent polluted discharges to the street gutter and storm drain systems, to keep clean rain water clean.  Some common examples include meshed straw waddles around a lots perimeter, a contained wash-out area for concrete or paint, plastic sheets over stockpiles, and sweeping the street frontage daily help to keep sediment from reaching the storm drain. These protection measures, commonly called Best Management Practices (BMPs), are temporary and need to be maintained frequently to work properly, especially during frequent winter rains. Erosion Control information can be found on the following websites:

We are all a part of neighborhoods, community, and the incredible environment we call home.  One last way to support our home is to Report Spills or polluted discharges to the storm drain system (streets, inlets, pipes, ditches, and creeks). Report hazardous or unknown spills to 911. Report non-hazardous spills based on where you are in the watershed.

  • Cloverdale     707.894.2526
  • Cotati             707.665.3605
  • Healdsburg   707.431.7000
  • Rohnert Park  707.588.3300/after-hours 707.584.2600
  • Santa Rosa      707.543.3800/after-hours 707.543-3805
  • Sebastopol      707.823.5331/after-hours 707.829.4400
  • Unincorporated County of Sonoma 707.5.1900
  • Windsor          707.838.1006/after-hours 707.838.1000
  • Ukiah              707.463.6288
  • Unincorporated Mendocino County 707.234.6679
This article was authored by Forest L. Frasieur, of Santa Rosa Water, on behalf of RRWA. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, habitat restoration, and watershed enhancement.

Managing Trash and Reducing Litter

Do you like seeing trash and litter on our sidewalks, streets, yards, and waterways? We didn’t think so. Not only do our open spaces look better when they are clean and tidy, it contributes to a healthier environment.

Trash and small debris pieces left in open areas may be carried by rainwater to storm drains. Smaller items such as motor oil and pesticides may flow into storm drains, which could lead to rivers, lakes, and streams. Large items may block storm drains and can cause road and structure flooding during storms.

Additionally, litter effects the quality of waterways that provide recreation for many residents and can harm aquatic and other wildlife. Animals can ingest toxic substances such as paint or household cleaners, or they might swallow or become entangled in the trash that finds its way into streams. Fertilizers from yard waste dumped into streams can create large algae blooms that kill fish.

Common forms of litter include:

  • Cigarette butts
  • Plastic bags and bottles
  • Aluminum and glass containers
  • Paper products
  • Household hazardous wastes
  • Motor oil
  • Used food containers and unwanted food
  • Diapers
  • Yard waste

Small amounts of litter from homes or neighborhoods add up to big problems.

What can you do? A healthy, vibrant community that is free from trash and litter takes commitment and investment. Each person can make a big difference to keep our waterways clean.

  • Storm drains are not trash cans. Please do not throw anything into the streets or storm drains.
  • Please don’t litter. Make sure that your trash does not enter waterways. If you see litter, pick it up, and dispose of it properly.
  • Ask for help. If you see a problem area (i.e., a trash can overflowing onto and/or along the sidewalk), inform your City or trash hauler so they can address the problem.
  • Use your consumer voice. If you notice a lot of litter near your favorite shop or restaurant, encourage the business to add more trash and recycling receptacles.
  • Reach out to your local government representatives. Let them know that trash mitigation and stormwater management are important to you by asking tough questions about what resources are currently being allocated to address these issues.
This article was authored by Angela Beran, of the City of Rohnert Park, on behalf of RRWA. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, habitat restoration, and watershed enhancement.

Alternative Water Sources – Greywater Reuse

Traditionally, each step of the human water cycle – how we acquire, treat, use, treat again, and dispose of the water, was dealt with as discrete, isolated activities. Separate departments, divisions, and districts were created to handle each of these isolated activities. Unfortunately, this traditional recycled water paradigm sometimes also comes with a high-priced additional expense of duplicate infrastructure to re-transport the recycled water back to the users, thus limiting the number of users that can be served. The main use of recycled water is irrigation of crops and large landscaped areas such as golf courses, athletic fields, commercial and industrial parks, and cemeteries. More recently, its uses include process water for industry, wildlife habitat enhancement, residential landscapes, fountains and more.

There is a way for individuals to irrigate their homes with mostly clean, unpotable water. This is called greywater reuse. Greywater resides between clean, treated for human consumption, potable water, and blackwater from toilets. The difference between recycled water and greywater is the latter is not treated by a treatment plant. It can be defined as any domestic wastewater produced, excluding sewage, and typically comes from showers, non-kitchen sinks, laundry machines, and other similar plumbing fixtures. Ranging from simple to very elaborate, greywater systems can be routed to your landscape to help meet your irrigation needs and can possibly help create a fire-resistant yard!

Brian Thacker, Arizona Renewable Resources, searched through Google Earth studying satellite images of the catastrophic Rodeo-Chedeski fires that burned in east-central Arizona in June/July of 2002 and came upon something amazing.  In the middle of a charred landscape of burned pine trees, he saw two green areas surrounding two undamaged homes—a thriving oasis amidst devastation. He needed to know why these homes were spared a fiery end and contacted the area fire marshal to investigate.  Brian found that the homeowners did two key things:

  • First, they used fire-defensive practices in their landscape. Within a 50- to 75-foot radius around their homes, they removed all ground-ladder fuels that could spread a low-burning fire into the canopy of trees and shrubs.  They pruned tree branches up 4 feet from the ground; cleared, chipped, and shredded dead limbs and brush; spread resultant mulch over the soil to retain soil moisture; removed conifers and shrubs next to or against the house; and cleared pine needles from the roof and gutters.
  • Second, the homeowners directed their greywater into the surrounding landscape, particularly the oasis zone around their homes. This supplied the native vegetation with enough moisture to keep it from igniting so it acted like a fire break around the homes.
    3-way valve to divert the laundry greywater

Greywater irrigation is one tool to be used in preventing damage from wildfires. Existing homes and businesses can be retrofitted but installing greywater plumbing is easier and less expensive in new construction. A Greywater Ready Model Ordinance is available (https://oaec.org/wp-content/uploads/2018/02/Greywater-ready-buildings-model-ordinance.pdf) that details greywater plumbing installation. Sonoma County Water Agency and others offer training for designing/installing these systems.  If you’re interested in learning more about greywater use and permit requirements, contact your local Building Department.

Greywater helps to reduce sewage treatment costs, disposal requirements, and can help protect homes from future fires, all while helping to recharge the groundwater as well. That’s a win-win-win.

This article was authored by Dirk Medema, P.E. who is the Drainage Engineer of the City of Citrus Heights, on behalf of RRWA. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, habitat restoration, and watershed enhancement.

Creek Week Volunteer Opportunities

Throughout the Russian River watershed, the third week of September is recognized as Creek Week. This year Creek Week is from September 15 to September 22. During Creek Week, creek, river and ocean clean-up campaigns will take place throughout Sonoma and Mendocino Counties. The Russian River watershed consists of over 150 creeks which provide water supply, wildlife habitat, flood capacity and recreation. Unfortunately, trash and debris accumulation in local waterways impair water quality, wildlife habitat and, at times, recreation and flood capacity. This is a great opportunity to take part in activities that connect you with your community and environmental practices that help protect our creeks.

You can contribute to the health of the Russian River ecosystem by participating in one of the creek and river cleanup events listed below!

September 15, 2018


September 22


Composting…Don’t throw it away, compost it!

There are vast benefits to composting, not only environmentally, but also personally within your home. Using compost in your home garden adds nitrogen, potassium, and micro‑nutrients such as manganese, iron, and zinc. These additions strengthen the structure of your soil, retains water in plant structure, prevents erosion, and is ideal for drainage.

There are two ways to go about composting based on your available space. If you have limited or no outside space then you can use a specially designed bin for indoor use that can be purchased from a local garden store, hardware store, or even via the local paper want-ads. For those with outside space, select a dry area with shade that is close to a water source and dig out a desired space e.g 3’ x 3’ x 3” depth or what every size you feel is adequate, and now it’s time to start creating your compost.

In selecting your compost think of two categories: home and outside. The home category is food from your home including fruits, vegetables, nut shells, coffee grounds, tea leaves, but excludes dairy products, meat or fish scraps, and grease. The outside category includes items from your yard, such as leaves, branches, yard clippings. Note: compost items should not be chemically treated. Make sure to cut large materials like banana peels and break down branches to aid in the breakdown process. Lastly, make sure to layer your compost alternating between home items and outside items, and try to keep each layer similar in size.

Every two weeks or so, while tending to your compost, whether you are simply checking on it or adding to it, it is important to mix your compost. How can you tell if the compost is ready? That will depend on the material being composted and its environment. I suggest researching your material and the environment where you’ve composted to get a better understanding on your compost and the process. Generally speaking, the appearance of compost that is ready will be crumbly and may be slimy in consistency, dark in color (like soil), and have an earthy smell. Now, you can use it to plant flowers, trees, vegetables, and use it as top soil. It can also be used for putting in a new lawn, installing a new eco-friendly landscape, or simply used for rotating your vegetable garden.

There are many benefits to composting. It is known to regenerate soil by promoting the production of micro‑nutrients, which break down the organic matter and in turn retains moisture and increases the content in the soil through a process called humus. Given that 95% of our food comes from our soil, it is critical to consider soil quality. Compost can also clean up the contaminated soil by absorbing volatile organic compounds (think pesticides) that may be found in your soil. Also, carbon released from farming heats up our Earth’s climate and melts polar ice caps, which is another reason composting is an important practice that contributes toward protecting our ecosystem. Furthermore, if all countries put 0.4% of their carbon back into their land, it would produce 75% of all of Earth’s carbon back into the Earth’s soil.

Other benefits of composting include preventing soil erosion, which is especially important if you live near creeks or storm water drains. The compost can slowly preserve the amount of sediment runoff that spills into our waterways, that drain into our rivers. This is imperative in protecting these waterways as they are the ecosystem for our fish and other inhabitants living in the rivers and oceans.

Composting and sustainability should be on the forefront of our minds. Composting is an incredibly versatile practice that supports erosion control and provides many benefits for gardening, our waterways, and our ecosystem as a whole.

This article was authored by Joshua Ricci, of Permit Sonoma, on behalf of RRWA. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, habitat restoration, and watershed enhancement.

How the October 2017 Wildfires Affect Local Hydrology

On Monday, October 9, 2017, many local Mendocino, Sonoma, Napa County residents woke to falling ash, intense winds, and a red glow in the distance. Five wildfires broke out in these three counties within hours of each other: Redwood Fire in Redwood Valley, Mendocino County; the Pocket Fire, Tubbs Fire, and Nuns Fire in Sonoma County; and the Atlas Fire in Napa County. The wildfires destroyed thousands of homes and scarred 400 square miles of land. Even though the wildfires were contained, the effects on local economics, social safety, natural resources, housing, and hydrology will be felt for years to come. This article describes our current knowledge of how wildfires affect hydrology and how Northern California differs from other places that have been studied in the past.

Imagine a gently-sloping, one-acre field of grass with an oak tree in the center. Before the wildfires, when rain fell from the sky, water was captured by blades of grass and oak tree leaves. Rain that surpassed these barriers either soaked into the soil or flowed down the gentle slope towards the nearest stream. During the wildfires, grass quickly burned away and soil was charred from heat and covered in ash. The oak tree fell and burned, leaving a thicker layer of ash.

Now consider a post-wildfire precipitation event. The one-acre area is covered with a layer of ash, potentially several inches thick. Water is no longer captured by blades of grass or leaves of the oak tree. Water falls directly to the ground, but cannot soak into the soil (infiltrate) because the ash has wedged itself in the pore space of the soils and created a hydrophobic water repellent seal. The only direction for the water to go is down the gentle slope and into the nearest stream. This has serious impacts to local hydrology. Flash floods occur faster and the post-wildfire flow rates can be double the pre-wildfire flow rates. Russian River floods potentially may cause more damage and occur more frequently. Surface water quality is impacted by increased concentrations of debris, ash, and sediments. The big issue though is that the effects of the ash on the soil do not go away for between two and seven years according to research conducted in New Mexico and Colorado (Martin and Moody, 2001).

The ability for post-wildfire soils to infiltrate rainwater depends on four primary factors: (1) geology, (2) ecology, (3) burn intensity, and (4) the time since the fire. Clay soils already have low infiltration rates compared to sandy soils. Remembering our example of the grass and the oak tree, the grass ecosystem recovers faster than theoak tree ecosystem, because the oak tree ash layer is thicker and burns hotter. Hotter burns generate white ash that is more hydrophobic than gray or black ash, and takes several more years for fire recovery (Harding, 2018). Our understanding of how wildfires affect hydrology in Northern California is limited, because previous studies have been conducted in regions with different geology and ecology. Johnathan Perkins of the United States Geological Survey (USGS) is working on a study to quantify how infiltration rates change over time in a number of different burn areas in Northern California. Preliminary data has shown that infiltration rates are still decreasing since the wildfires indicating that the chemical and biological processes that seal soils may still be getting worse (Perkins, 2018). Relationships between infiltration rates and local geology, ecology, and burn intensity still are being developed. This USGS study will move us forward in developing our understanding of long term effects of the wildfires on our local hydrology.

Even though the wildfires are many months behind us, the effects that wildfires had on our local environment will be felt for years. Climate predictions indicate greater intensity storm events and increased frequency of atmospheric rivers hammering our region with greater flow rates during floods. These externalities, coupled with sealed soils, are of great concern to our local ecology and socioeconomic stability. Local stakeholders, agencies, government, utilities, and residents are working closely together to mitigate risks. It is up to us, the community members, to understand the risks and be prepared for what Mother Nature can throw at us.


Martin and Moody, 2001. Comparison of soil infiltration rates in burned and unburned mountainous watersheds. Published in 2001 John Wiley & Sons, Ltd.

Harding, Mike, 2018. Fire and Rain: Post-Fire Hazards and Mitigation. Presentation at the Changing Channels Conference: The Science of Stream Processes and Restoration in the Russian River Watershed. Cloverdale Citrus Fairgrounds Auditorium. January 26, 2018.

Perkins, Jonathan P, USGS, 2018. Presentation for the Russian River Science Forum. May 2, 2018.

This article was authored by Brian Wallace, of LACO Associates, on behalf of RRWA. RRWA (www.rrwatershed.org) is an association of local public agencies in the Russian River Watershed that have come together to coordinate regional programs for clean water, habitat restoration, and watershed enhancement.