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A Watershed View of Problems and Opportunities for the Russian River

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Water and Wildlife: A Watershed View of Problems and Opportunities for the Russian River

By Don McEnhill

Two important documents on the Russian River came out late this summer that offered two different pictures of our watershed and most people are focused on only one of them. The first is the Draft Environmental Impact Report for the “Fish Habitat Flows and Water Rights Project” (Flow EIR) that concluded we need to reduce summer flows by 44% to improve habitat for Endangered salmon and steelhead. The second document was the Russian River Independent Science Review Panel Report (IRSP Report) on watershed hydrology and stream ecology, in other words the science around the movement of water and it’s relationship to wildlife and fish habitat. It’s the Flow EIR that has everyone talking, but the ISRP Report is far more comprehensive and focused on the biggest issue in our watershed.

Fish FarmIf we had to point to the one thing that we believe is the biggest problem for the River it’s the almost complete disconnection of our River from its former floodplains. For a river not having a floodplain is like a car with no motor, it just won’t do the job we want it to. 

Historically rivers such as the Russian River provided valuable “ecosystem services” to the watershed that we no longer enjoy. Ecosystem services are services valuable to people that healthy natural systems provide for free that are worth millions to billions of dollars. Ecosystem services are things such as food for 50,000 juvenile salmon, natural flood protection, groundwater recharge, water purification and climate regulation. Today we know those services have been greatly diminished or lost due to what we have done to our watershed before we understood the possible impacts.

Fish SizeHow did we lose potentially Billions of dollars worth of free natural services? Simple, we cut the River off from spreading on to its floodplain during the rain season because of channelization, mining and thousands of dams large and small. These actions have resulted in the river’s bed down-cutting or incising up to 25 feet in some parts of the Russian River. The graphic below illustrates this dynamic by showing the riverbed elevation in the 1940’s and today. 

“At the same time as we have dropped the elevation of the bottom of the river, we have straightened and simplified the river and many tributaries with bulldozers. This river engineering eliminated the old river meanders, wetlands and about 80% or more of the area the river used to occupy. The aerial view graphic of the river in 1942 and in 2005 below shows that the Russian River lost 75% of the former river area, just between Healdsburg and Wolher Bridge. The River used to occupy 3,257 acres in 1942 and in 63 years it was shrunk to 807 acres. Put in other terms we have put the Russian River into a strait jacket that is 3 sizes too small and turned the Russian River in many parts from a river with floodplains and wetlands into a simple ditch with trees on the sides. We have a car with no motor but the river never gives up that easily.

Why is a straight deep channel a problem? It certainly provides more land for development for farming and other land uses. The reality is the loss of river area comes at a steep price – steeper than the hottest selling pinot now grown where the river used to be. Back in 1942, when the river rose it spread out and moved pollutants like silt into seasonally flooded areas away from the main channel, where it wouldn’t harm fish or drinking water sources. In 1942 the river would spread out and slow down and recharge our groundwater, today the river just rushes out to the ocean with little recharge except during extreme flood events every ten years when it reaches the floodplain. This also provided natural flood control in slowing down water and spreading it out, today it all goes straight to Guerneville and increases flood heights rather then be temporarily stored in the floodplains. When the river spread out on to the floodplain, it increased the river area dramatically and flooding fields that increased the food supply for salmon by thousands of times. This we know to be true from studies that show salmon put in 3 foot deep pens in rice fields (pictured below) grow twice as fast as fish in the Sacramento River, which is a narrow deep ditch just like our river with less trees. Like any wildlife population, the biggest regulator for Salmon on the Russian River is how much food it makes. When you shrink the river by 75-80% it produces that much less food and therefore we have less salmon

All these problems will get worse – far worse with a changing climate. In the simplest terms, the hotter the air temperatures, the more extreme the weather is on both sides of the coin. When we have floods, they will be much bigger, when we have droughts they will be longer and have more dire effects due to hotter temperatures. Water is a major part in seven out of ten jobs in our watershed so a prolonged ten year drought would devastate not just our environment but our economy. The time to act is now before the next drought or next flood when those bigger storms do hit us, it’s too late to act. What kind of future do we want in the watershed, one of tipping from one disaster to another or should we invest the time and money now to avoid them completely or reduce the impact to manageable levels?

It’s obvious to many we have a very big problem and the next question is, can we fix it? Luckily that answer is yes, we can undo our past actions to provide more space for the river and creeks and get back many of those lost ecosystem services. This is why Riverkeeper after fighting with gravel miners for decades, is now working with them to restore former gravel pits back to floodplains. We’ve spent considerable time and effort over the last four years with Hanson Aggregates to come up with a plan to turn their pits into floodplains. This is a big deal as land along the river is very expensive but Hanson is willing to give the restored floodplain area – 350 acres to Sonoma County Regional Parks for a public park. A UC Davis study shows us that adding this much area will boost groundwater recharge by more than double. This is a win-win for the river and the community and increases the size of the middle reach by 30% in one project and feed up to 100,000 juvenile salmon! 

There are other means of accomplishing similar outcomes of restoring ecosystem services closer to your home so you can help too! Changing landscaping to slow down water and temporarily detain it in swales will increase the amount that seeps into groundwater and decrease the amount that goes right to the river and makes floods worse. Rain barrels are another way to slow water down so it all isn’t going to the river at once. This is a big help until we get more big landscape projects like the Hanson pit restoration completed.