You never know where a conversation will take you. This one started with a conversation about the best puffy jackets at a conference, and ended with me perched on a tailgate wrestling with pipe fittings in an apple orchard.
So even I, an avowed introvert, have to give small talk some credit. This summer I’m working with the Oregon Water Resources Department (OWRD) evaluating the chemistry of groundwater in the Oregon side of the Walla Walla Basin! It’s a win-win scenario: they get a low-cost field technician, and I get to use the data we’re collecting to support my thesis looking at the spatial distribution of the water chemistry. I’m really excited to learn more about how the state manages these resources, and am grateful for access through them to the ability to sample from both public and private wells during their routine visits.
To learn more about what this research entails, check out the link below, and then come back to this page to read more about the field work that will make it possible.
(down for maintenance, sorry) Click here to go to the “story map” website I created to introduce my research
In short: agriculture in the Walla Walla Sub-Basin of Oregon (WWSB) depends heavily on groundwater from the deep layers of basalt. Those groundwater levels are declining and the OWRD is trying to figure out how the aquifers work and what would be the fairest way limit use to more sustainable levels. My research focuses on a spatial approach to this problem: how does groundwater interact with the faults in the basalt, based on chemical, geologic, and hydrometric data? Should the faults be taken into account when allocating water rights?
This project is spearheaded by Jen Woody, a hydrogeologist at the OWRD, and she and I are also collaborating with the US Geological Survey to build on their studies in the region and laboratory capabilities. In return for the ability to put our results in their databases, the USGS is giving the OWRD team technical support, the use of their sample bottles, prep lab access, and assorted sampling gear. With training complete and the gear piled into the back of a pickup truck, Jen and I spent the past week based out of Milton-Freewater. It’s also known as “Muddy Frog-Water” (don’t ask me why…) and grew along with its wheat fields and apple orchards on the banks of the Walla Walla River.
A day of sampling started a 7:30, when Jen went into the Safeway to get a couple bags of ice for the coolers and I set up shop on the tailgate calibrating the pH, conductivity, and temperature meter in brightly colored solutions. We then hit the road and headed out to the first well of the day.
We had picked out wells to sample ahead of time based on geology, GPS well locations, and well log characteristics, but those plans had to be flexible. Things that look so simple in ArcGIS are always more complicated in reality. Access to wells depended on who Jen had been able to get in touch with, whether the farmers were pumping that day, and whether there were sample ports on the well. Wells in the basalt aquifer here are deep – most are between 600 and 1000 feet – and the huge turbine pumps that access that water can cost up to $10,000 per month to run. They’re not something that we could turn on casually to get samples!
After we beat back the tumbleweeds, found an outlet on the well, and ‘MacGyver’ed some combination of hardware to linked that outlet with our sampling pressure fitting, it was time for science. At each well we took measurements for pH, conductivity, and temperature, and filled bottles with water to analyze for alkalinity, ions, oxygen and hydrogen isotopes, tritium, and carbon 14. Those bottles then got safely stowed in coolers until we drove them to the USGS lab on Friday. If you skipped the story map link, the images below outline what we’re sampling and why.
Our record was five wells and a surface water sample in one day. We had a break before a 5pm appointment at a well that day, so we just had to drive out of the blazing hot valley and up the canyon to a cool and shady park to take another isotope sample from the river… life is tough.
Finding the secondary well outlet sounds easy in theory… and then we ran into these mazes of pipes.
In addition to collecting samples it was also great getting to talk with the farmers who were giving us access to their wells. We even got a tour of an antique saddle restoration studio from one of them.
It rained on Thursday, which brought the temperature down nicely but meant that pumps weren’t running. No irrigation meant no sampling, so Jen and I took a geology break up in the hills above Walla Walla to admire outcrops of the basalt that also form the aquifers deep below the valley.
The goal of our sampling is to evaluate how the faults in the region affect groundwater flow, so it was great seeing examples up here in the hills. Faults were visible as breaks in the horizontal structure of the cooled lava flows, but their size varied widely. Some faults looked simply like the rock had been cut and one side moved, while others took the form of 50 meter wide zone of pulverized rock! This was definitely food for thought when considering the faults on the map. I’ll have to do more research to see whether the ones I’m studying are of the 5 inch or 50 yard variety.
At the end of the day we retreated to the air conditioning and giant plates of food at La Ramada, which along with the Dairy Queen and El Sombrero represented the sum total of dining options of Milton-Freewater. The Hank FM country station was kind enough to info us that the local cider brewery, Blue Mountain Cider, had a tap room open on Thursdays. It was a treat to finally taste the apples we had been working among all week, especially in liquid form after a hot day.
We got a total of 12 wells sampled last week. Jen and I are heading back out later this month to try to knock out the next 9 samples and to see if there are any additional wells where we can just take samples for oxygen and hydrogen isotopes. Additionally, we’re doing the OWRD’s quarterly check of water level recording equipment in wells around the area. Stay tuned for Part 2!