Challenges to a Water Supply in a Changing Climate
The Community Research Project was conducted on behalf of the Whatcom County Climate Impact Advisory Committee. The purpose of this project was to reach out to community leaders and stakeholders on how the county should address the growing impacts of climate change. The entire report is posted at: www.whatcomcounty.us/DocumentCenter/View/43718/2019-Whatcom-County-Community-Research-Project.
by Judy Hopkinson and Ellyn Murphy
Your body is about 60 percent water. But that water does not really belong to you. As Archie Bunker said about beer — you just rent it. The molecules of water flow in and out of you and will be part of the river or a plant or a fish or your neighbor in a few days. So we are all water beings, bound together by this common vital element that cycles through the ecosystem of which we are each a part.
When there were fewer of us, water cycling was easy to ignore because water seemed to be in endless supply — especially here in the Northwest. Our rushing rivers full of fish, pristine lakes, shallow aquifers, ample rainfall, and mountain glaciers melting slowly during the dry summer months gave us all the water we could ever imagine needing.
But things change. Population pressure increases demand and competition for water — especially during the dry season in July and August when irrigation needs are at a peak. Water withdrawn upstream in sufficient amounts reduces both instream flow critical for fish habitat and irrigation water available downstream. Water withdrawn from shallow aquifers that intersect a streambed, called hydrologic continuity, may reduce water levels in nearby streams.
The concept of water “rights” was developed to reduce conflict and to ensure that those who needed water for established needs would have it. In Washington state, water rights are prioritized — those who received water rights first have priority over those who came later, “first in time, first in right.” This worked pretty well as the West was settled. But, here in Whatcom County, we had a problem. Our seemingly endless supply of water lulled us into a very casual application of the water rights’ concept. Mostly we ignored it. Even today, about 40 percent of water used to irrigate crops is withdrawn without a legal “right” to the water taken. (1) Water did seem to be in endless supply, after all. In truth, we had no idea how much water we had available, so even when we did assign water “rights,” they were dispersed without knowledge of water supply.
At this point, Whatcom County does not have enough readily available water for both crop irrigation and fish habitat in the summer months. We need both healthy streams and healthy crops to maintain our way of life. Unfortunately, the situation is becoming more problematic as the population expands and as the climate changes.
With climate change, more of our precipitation is coming as winter rain and less as snow. This means higher stream flows in the Nooksack River during the winter (and therefore greater flood risk) as shown in above chart. (2)
“Much of the flooding we have recently experienced is related in part to the fact that we have tightened the river channel to the point that it no longer has room to handle high-volume events,” according to Chris Elder, Whatcom County’s senior planner in watershed management.
Conversely, because glaciers are receding and snowpack is melting earlier in the year, the future will see marked reductions in the late summer stream flow in the Nooksack River basin.
Spring snowpack that feeds the Nooksack is projected to decline almost 30 percent by the 2040s and stream temperatures are projected to increase by 2.6 degrees Fahrenheit as sunlight penetrates and heats shallower waters. In about 20 years, 40 miles of the Nooksack River are projected to exceed salmon thermal tolerances compared to zero miles today.
Glacier loss exposes underlying silt, which washes downstream clouding the water and reducing stream depth. Cloudy water is problematic for fish which cannot as easily spot insects or other food sources. In addition, silt deposits increase flood risk for nearby communities because streams and rivers are more likely to overflow their banks during heavy rains. Sea level rise will further slow river discharge into the ocean, increasing the backup of flood waters. This can be especially severe when combined with storm surge and high tide.
Climate Change in the Nooksack River
We can look at the projected impact of Climate Change in the Nooksack River basin (see chart above) to gain a picture of the way climate change will impact water issues in Whatcom County. (2)
Planning for Practical Solutions
Planning for practical solutions to water challenges will differ from one part of the state and county to another. So, the Washington State Department of Ecology and other state natural resource agencies have divided Washington into 62 “Water Resource Inventory Areas” or “WRIAs” for the purpose of water management planning, salmonid recovery planning, and ecosystem planning. (3)
Most of Whatcom County’s population, and most of our agricultural land, lies in the very top WRIA on this map which is designated WRIA 1:
Within WRIA 1, there are multiple drainage basins with somewhat different challenges. Both county government and stakeholders have come to the realization that basin-based planning is essential and that no single set of practices should be prioritized for all drainage basins. For example, switching to groundwater withdrawal for irrigation may work well in some basins, but not in others, and careful timing of field drainage to enable spring planting and maximize retention of soil moisture may be more critical in other areas. Practices critical within a mile or so of streams and rivers will differ from critical practices farther from surface water sources.
Water Use in Whatcom County
Agricultural irrigation is by far the dominant use of water in Whatcom County, accounting for 44 percent of the total annual water use, followed by industrial (24 percent) and residential (20 percent). (4) The remaining 12 percent, “Other,” is divided among livestock, aquaculture, mining and commercial.
As you might expect, almost all of irrigation water use is seasonal, usually starting in May and ending in October. Agricultural irrigation accounts for almost 70 percent of the water used during the critical summer months.
Water Sources in Whatcom County
The water we use in our county comes from our rivers, from aquifers, and directly from rainfall. The Nooksack River is the primary source of surface water for the county. Water diverted from the middle fork of the Nooksack into Lake Whatcom, combined with rainfall in the Lake Whatcom drainage basin, constitutes the source of water for about half of Whatcom County residents.
“About 20 percent of irrigation water for agriculture is drawn from the Nooksack River system and the remaining 80 percent from groundwater — mostly the Abbotsford-Sumas Aquifer, a shallow aquifer that extends into Canada,” according to Henry Bierlink, administrator for the county Ag Water Board of Whatcom County. The depth of the Abbotsford-Sumas Aquifer varies, but is about 40 feet below land surface near Lynden.
The problem with drawing large amounts of water from shallow aquifers is that these aquifers may have a hydraulic connection to surface water streams. So, if large quantities of water are pumped from a shallow aquifer, enough to cause groundwater levels to decline, this may also reduce the water level of a nearby stream or river.
Unlike many other parts of the country, we currently draw very little water from deep aquifers that would be less likely to have hydrologic continuity with nearby rivers. Recently, however, both the Birch Bay Water and Sewer District and the City of Ferndale have drilled deep groundwater wells that tap into confined aquifers well below the level of the shallow Abbotsford-Sumas Aquifer.
The Birch Bay and Ferndale wells will primarily be used for municipal water. The available data indicates that the recharge areas for both of these aquifers extends a significant distance into southern British Columbia. Also, the use of water from these deeper, confined aquifers is expected to have little to no influence on surface water and other groundwater sources. (5)
In practice, drawing water from deep wells for agriculture can be expensive due to the up-front cost of drilling and infrastructure for water delivery. According to Chris Elder, “If Birch Bay Water District drilled and installed piping, then it has been estimated that the water may cost as much as $400 per acre foot for irrigation.”
At this point, the science is just beginning to reveal the deep aquifer potential in Whatcom County and whether or not this groundwater will be suitable for irrigation. Untapped deep aquifers could help, but multiple solutions will be needed to solve our summer water supply challenges.
Several options have been explored to mitigate seasonal water shortages by better managing available supply. For example, one seemingly logical mitigation effort would be to allow water rights’ holders to transfer unused water to other parcels of land or use it to augment stream levels for fish passage. However, this is risky for water rights’ holders because of the “use it or lose it” relinquishment provisions of Washington water law. If a water right holder has water to spare and is not actually using all of those rights for the originally declared purpose, then those rights could be subject to potential relinquishment.
The same would be true for a farmer who reduced water use by switching from spray to drip irrigation. Eventually the farmer would lose the right to the water saved, unless he or she applied to temporarily “donate” the water right to the Department of Ecology’s Trust Water Rights Program.
The water right relinquishment provision was introduced in 1967 in the hopes that it would free up unused water for streams and other needs. It seemed so reasonable — but it has had the unfortunate consequence of discouraging water conservation efforts. In this and other ways, Washington water law often limits creative solutions to water supply challenges.
Relinquishment can be avoided before the fact through two legal options; water trust accounts and water banks.
Water trust accounts — were established in 1991 by the state Legislature. This program created a statewide mechanism that allows rights’ holders to “park” unused water rights with the state. Donations to the trust can be temporary or permanent. However, the donor must be able to demonstrate that their full water right was utilized in the past five years if they wish to retrieve the right at a future date.
Water banks/exchanges — allow the transfer of existing water rights from willing sellers to buyers on a temporary or permanent basis. Water banks exist in almost all western states. Although the approaches may differ, the common goal is moving water to where it is needed most. Anyone, including private developers, may purchase water rights and form a water bank under guidelines administered by the Department of Ecology. In some cases, this can lead to the water bank broker charging exorbitant fees to users who need to purchase water rights either permanently or temporarily, thus profiting on public resources for private gain during periods of high demand.
Whatcom County’s Ag Water Board is now examining the technical feasibility and the pros and cons of establishing a water bank (or trust water rights program) either countywide or within specific drainage basins. The engineering firm RH2 Engineering, Inc., was hired by Whatcom County to prepare a technical memorandum on the topic which will focus on protecting conserved water from relinquishment due to nonuse.
The WRIA 1 Planning Unit is also investigating water storage and supply options that involve diverting and storing water when streamflow is high. Engineered solutions may be promising, but the details can be challenging. There are, however, proven strategies that could be more widely applied. Enhancing wetland ecosystems, increasing organic matter, and encouraging floodplain connectivity are all proven strategies that can contribute to late season water availability.
Fish habitat will be improved though augmentation of instream flow rates, but other factors are also critical. The four major components of a stream system that determine productivity for aquatic organisms are:
1. flow regime,
2. habitat structure,
3. water quality (e.g., temperature, dissolved oxygen) and
4. nutrient inputs from the watershed. (6)
Our rivers and streams historically provided miles of shaded pools and oxbows where salmonids and other fish could rest and feed in cool waters with ample nutrients as they made their way downstream. From the time settlers first arrived to the present (about 160 years), between 50 and 90 percent of the land along streams and rivers in the Puget Sound has been lost or extensively modified. (7)
The U.S. Department of Agriculture Conservation Reserve Enhancement Program (CREP) pays landowners to restore riparian zones along streams by establishing buffers of native trees and bushes. This program is managed locally by the Whatcom County Conservation District. While the main objective of the program is to restore and protect critical fish habitat, riparian buffers also provide habitat and travel corridors for a wide range of wildlife. Buffers of native vegetation help protect water quality, stabilize stream banks, reduce erosion, create shade that lowers water temperature, and provide attractive borders for privacy and protection.
Since 1999, landowners have restored more than 14,000 acres of streamside habitat and planted more than five million trees and shrubs. (8) This is probably less than half of the stream habitat that is in need of restoration. Moreover, the CREP program incentives have decreased substantially over the last three years, and, even at their peak, were far from sufficient to offset the financial impact to farmers of losing highly productive agricultural land along streams and rivers.
In the past decade alone, research by the tribes, universities, and government entities has added critical understanding of the ways in which our watersheds function and interface with plant and animal life. This ongoing research enhances our ability to develop technically feasible solutions to the challenges we face. Farmers, fishers, and government officials are using this information as they work together to find technically and financially viable ways to manage water resources in Whatcom County, while minimizing adverse ecosystem impacts.
After conducting some 20 interviews with stakeholders, researchers, and government officials, we have come to respect the technical complexity of the potential solutions to water supply issues, the challenges of collaboration between different stakeholders, the current and continuing impact of climate change, and most importantly the need for a better informed public to adequately and wisely monitor and support the work of our elected officials.
The policies we set now will determine the future health of our ecosystem and whether or not all of our children have the water they need for life and livelihood in the coming years.
1. The number “40 percent” was mentioned by numerous people involved in county water issues and agriculture during interviews for the Community Research Project (https://whatcomcounty.us/3162/Meetings-Additional-Information).
2. Floodplain by Design and The Nature Conservancy, 2018. “Climate Change in the Nooksack River: A quick reference guide for local decision-makers”: https://cig.uw.edu/wp-content/uploads/sites/2/2018/10/FbD_Nooksack-climatechange_web.pdf.
3. WRIA 1 Board Work Plan_Aug 1-2018_v.0926-2019.pdf: https://drive.google.com/file/d/1_9kDg_6ZM9rDuks4vQBPSGbUFf_lqnJo/view.
4. Hirst, E. “Analysis of Whatcom County Water Use,” January 2017: https://nwcitizen.com/images/fileuploads/Analysis_of_Whatcom_County_Water_Use.pdf.
5. Ferndale Shop Well #2 is capable of producing 300-350 gpm for extended periods of time and capable of producing 1,000 gpm for short periods of time (several weeks). “Installation and Testing of the Shop Well #2, Ferndale, WA, June 26, 2018,” by Associated Earth Sciences, Inc. Shop Well #2 is saline and would be treated by reverse osmosis before municipal water use.
The sustainable yield for exploration wells drilled by the Birch Bay Water and Sewer District was 650 to 544 gpm for EW-2 and EW-3 respectively. “North Whatcom County Regional Water Supply, Feasibility Study — Phase 1.” For the Birch Bay Water and Sewer District, February 2018, by Associated Earth Science, Inc.
6. Bandaragoda, C., Joanne Greenberg, and Mary Dumas (2013). “Data Integration of WRIA 1 Hydraulic, Fish Habitat, and Hydrology Models.” 134 pp. Nooksack Indian Tribe, Whatcom County, WA. WRIA 1 Joint Board.
Judy Hopkinson and her husband Dave moved to Bellingham in 2008. She received her Ph.D. in plant physiology from the University of Texas at Austin in 1974, and went on to teach and conduct research at Hiram College in Ohio and at Baylor College of Medicine’s Children’s Nutrition Research Center in Houston, Texas.
Ellyn Murphy is chair of the Whatcom County Climate Impact Advisory Committee. She has a master’s in forestry and a doctorate in hydrology. She spent most of her career at Pacific Northwest National Laboratory working on energy, environment and water issues before retiring and moving to Bellingham.