Questions and Answers on water for fish and Farms
To protect and improve salmon returns, including the prized Chinook salmon, we must also look to preserve our farms. It’s about protecting habitat and preventing the pollution that results from converting farmland to urban uses. Some think that we must choose between fish or farms. The facts show that not only is this not true, but that ensuring the future of our farms is essential to salmon recovery. The key issues are explained in our Fish and Farms White Paper.
Here, we delve a bit deeper into some important questions asked about this issue. Before farmers converted habitat to farmland, salmon were abundant. To recover salmon, shouldn’t farmland be returned to native habitat? There's no question that raising food has always affected the natural environment, including in ways that have negatively affected habitat. Habitat is essential for salmon, but it is one of a number of crucial issues including harvest. Farming activities began in northwest Washington in the late 1800s, including draining marshlands and adding flood controls. Despite this, fish numbers remained very high through the mid-20th century. Many other factors, including overfishing, contributed to this decline. Fortunately, much has changed, and the sustainability of farming continues to improve. While returning land to native conditions might be preferred by some, it is not a realistic solution today. Who would pay, and how much would it cost? Given all the complicated factors affecting salmon, even if all farmland were given over to habitat it would still not result in salmon recovery. Is there enough water for both fish and farms to survive? The simple answer is yes. The Puget Sound region is blessed with abundant rainfall. Climate change is affecting when our rain occurs and how much snowmelt is happening, but not our total rainfall amounts in a given year to meet the needs of both fish and farms. Despite this, fish can and do sometimes struggle with having enough cool, clean water in the summer. The resource needs to be managed better than it is now to make certain both fish and farms can thrive. Fish need sufficient water in our streams and the Nooksack river to survive, but flows are lowest at the times when farmers are using water for irrigation. How do we manage these flows so that both can thrive? Farmers take most of their irrigation water from abundant groundwater sources, not actually from our streams and rivers. Even considering the withdrawals farmers take from groundwater sources, the total amount of water withdrawn for farmers is a very small percentage of the available water supply. How much does water use by farms affect our salmon? Hydrogeologists, the scientists who support local governments with water supply information, have calculated the total amount of water used in the summer by farmers for irrigation at 36,856 acre feet. This was provided in a 2018 report to the Public Utilities District. The chart below shows streamflow for the Nooksack river measured at the Ferndale gauge. If farmers irrigate for 122 days as estimated, that means farmers use an average of 152 cubic feet per second (cfs) of water during the irrigation season running from June 1 to September 30. Flows in the Nooksack river vary considerably during the summer depending on the winter snowpack and how dry it is. For example, during the June 1 to September 30 window in 2012 the flow as measured at the Ferndale gauge averaged 4,043 cfs per day while in 2015 it averaged 1700 cfs per day. The average over the last ten years is 2,690 cfs per day. So, even in the most extreme circumstances, even if all farmers took all their irrigation water from the river at the times of lowest flow (which they don’t), they would only use about 5% to 6% of the flow of the river during the irrigation season. If the previous example is the most extreme, what is the most likely scenario? The actual impact on the flow of the river, and therefore any impact on fish, is usually much less, for several reasons. The reason is that most farmers no longer withdraw water directly from the Nooksack or streams. The above estimates are based on direct stream and river withdrawal. Irrigation water from the groundwater has a much less direct impact on stream flow than surface water withdrawals do. That means that the average shown of 6% is considerably higher than actual based on the source of water alone. Plus the impact on fish is far less than a withdrawal directly from the streams at the height of summer would be. Here’s why the impact is less when taking water from the ground: groundwater withdrawals can affect flows in the streams and the river depending on a number of factors including distance from the stream and the permeability of the ground. But, in Whatcom County with the very large aquifer and the recharge of that aquifer with the first rains of fall, by the time it takes for the irrigation water use to impact flow, the low flow season is past and such withdrawals have little to no effect on fish. It would appear that withdrawing water from wells is better for the environment than from rivers and streams. Why don’t more farmers do this? Farmers originally had rights to take water directly from the river and the streams feeding the river, but as the potential impact on fish became known, many farmers converted their “stream water rights” to “groundwater rights.” There are two reasons why all farmers haven’t done this. First, some farms are in areas where groundwater wells aren’t an option, so they have no other choice but to withdraw from the stream. Also, converting existing rights to withdraw from the stream to use groundwater can be very expensive, even if it is allowed. Why wouldn’t converting surface water rights to groundwater be allowed? A very unfortunate court decision known as the Foster case has kept farmers from doing more of this. In this decision, the judges without sufficient scientific basis concluded that withdrawing from the large aquifer equated to taking water directly from the river or streams. So, state policy under this unfortunate decision right now prevents the remaining farmers from converting rights from streams and rivers to groundwater despite it being better for the environment. See below for an explanation how taking water from the aquifer has very little to no impact on stream flows in the low flow seasons. This is one of a number of examples where effective water resource management for fish and farms is needed to address harm done by a court decision. Won’t withdrawals from the aquifer also take water from the river? The groundwater aquifer used is massive and the amount farmers withdraw during the summer is a very small percentage of the water it contains. While some farming areas across the country have seen their underground aquifers greatly reduced from irrigation and flood controls, in our case our aquifers are replenished to overflowing almost as soon as the fall rains arrive. This is seen in the flooded lowland areas throughout much of farm country. As mentioned above, groundwater withdrawals can affect flows in the streams and the river depending on a number of factors including distance from the stream and the permeability of the ground. Timing is one of the most important factors. In Whatcom County with the very large aquifers and the recharge of those with the first rains of fall, by the time taking irrigation water from these aquifers can affect the flow, the low flow season is typically past and the river and streams flow stronger with rains and snow melt. This timing means the impact on flow needed for fish from groundwater withdrawals is most likely negligible, if it exists at all. If farmers are having even a small impact on stream flow, low flows in our streams can still harm fish. Are there other things farmers can do to help fish during this critical time? Farmers have led the way in improving stream flows by diverting their water rights to use groundwater to replenish the water in streams. By directly pumping water from a well located some distance away from the Bertrand creek to minimize near-term impact on streamflow, farmers provided cold, clean water into the stream without reducing the flow in the stream at all. If withdrawing from the groundwater reduced flow in the stream in an equal amount, as the Court concluded in the Foster case mentioned earlier, that would have been evident in the carefully documented results. But the amount of water that was pumped into the stream was accounted for some distance downstream as predicted. Flow in the stream temporarily increased with no decrease in flow later on. Whatcom Family Farmers produced a video about this stream augmentation project and you can view it here. Withdrawal from groundwater can impact stream flows in the river and streams, but the key is timing. Hydrogeologists report it can take days, weeks, months or years for the impact. That means by the time any impact is seen in the streams, the fall rains and winter snows have arrived and the flows are well above the minimums. Groundwater withdrawals therefore have little to no impact of fish. Isn’t the amount of flow in our streams and river set by the state Department of Ecology to protect fish? Yes, in the 1980s Ecology established the instream flow rule which establishes the amount of flow Ecology has determined that is required to meet the needs of fish. When they set this rule and the amount of water the river and streams need for fish, any new water rights for farmers were issued as “junior” rights––that is secondary to the flow levels set by the state. This has resulted in a significant impact on farms. Now, if the river or stream is lower than the threshold set by the state, the farm with the junior rights has to stop irrigating. That can easily mean loss of crops and significant financial harm to the farmer. But doesn’t that rule protect fish, even if it means some harm to farmers? Farmers fully support keeping sufficient water in the streams, and have even taken the lead in augmenting streams at times of low flow. This was pointed above in the Bertrand augmentation project. The concern is that the rule is not sufficiently based on science and creates unneeded harm in most circumstances. A more science-based approach would protect fish without the associated harm. As farmers have demonstrated, there are methods available to enhance stream flow at critical times without taking water away from farmers needed for crops. Far too often the current instream flow rules do not provide the help fish need while causing unneeded harm to farmers. What do you mean by “more science-based?” Before Europeans arrived and significant farming activities began, the streams and rivers were naturally low at times during the year. The instream flow rule Ecology put in place is mostly based on what the average flow for the river was for a given time period. A few rules may have been based on habitat data. In an “average” year 50% of the time the river would be under the instream flow. The chart above tells the story. A look at the average daily flow over the past ten years shows why this is true. The flow, as noted above, varies considerably. In 2011, a year of very wet weather, the river flowed above the instream flow threshold for 80% of the time. In dry years, such as 2016 the river was above instream flows only 7% of the time. The average for the June-September time period in 2010-2019 is 46 days or 38% of the time year when the river meets the Ecology instream flow rule. Because the water withdrawn from the river is very minor even during the lowest flow, the chart mostly reflects natural flow. Ecology, through this rule is in effect saying, the natural flow in the river is in and of itself insufficient for fish. This cannot be scientifically justified. It’s one more example where resource policy and management decisions are contributing to the problems of securing the future of fish and farms. If there were no irrigation or farms, wouldn’t the flow in the river and streams increase? Very minimally. Using the same data as presented above, 152 cubic feet per second (cfs) of daily water used by farmers during the irrigation season would increase by 6 the number of days that the river flow would be above the rule. That moves it from 38% of the days below the rule to 42%. However, that significantly overestimates the actual days because, as we pointed out, most irrigation water is taken from groundwater and not the rivers and streams. As we also pointed out, the timing of hydraulic continuity (the impact on flows from groundwater withdrawals), means that the small amount taken from the aquifers does not typically impact flows until well past the low flow season when the river and streams have more water from rains and snow. So in actuality, taking away all irrigation would add considerably less than the 6 days shown. Removing irrigation would have very minimal impact on stream flows and the fish we want to protect. However, if irrigation stops, farms will be replaced by urban development. Homes, shopping areas, offices, industrial facilities, parks and golf courses also use water. So any potential streamflow benefit of stopping irrigation would almost certainly be offset by loss of habitat and urban pollution. Protecting farms is one of several essential steps to ensure the future and recovery of salmon in the Nooksack basin. |