“All life depends on it.”
This was the response I got when I asked Jonas Parker, Bureau of Land Management hydrologist, why anyone should care about hydrology. A no brainer, right? Well, sort of—Jonas elaborated, “hydrology needs to be functional. It needs to be in balance with the ecosystem it flows through.”
A System in Balance
We don’t just depend on water to live, but we depend on the regulatory processes that sustain a healthy water system.
Consider the human body—we need to take in a certain amount of water to be healthy. Too little water and you risk dehydration. Too much water and you risk overwhelming your body tissues. Our body systems help keep the body in balance, even when our choices may not. Overwhelm or abuse these systems and the consequence is death.
In the case of an ecosystem, like a forest, the same principles hold true. Too much or too little water can be devastating for an ecosystem. Natural processes and cycles help stabilize and regulate the hydrological cycle. Overwhelm or abuse these systems and we could be looking at ecological and societal collapse.
In either case, it is the system that needs looking after, not just the water flowing through it.
Land Management
As a district hydrologist for the BLM, Jonas’ job is to look after hydrological systems on our public lands. One of these lands is the Table Rock Wilderness area—which is where I met up with Jonas for our hike.
The Hike
- Trailhead: Table Rock Trailhead
- Distance: 7+ miles
- Elevation Gain: approx 2500 feet
- Details: We hiked from the Table Rock Trailhead to Rooster Rock Trailhead. Roads to both trailheads are gravel but in decent condition. Road to Rooster Rock Trailhead is a bit rough; high clearance recommended. Ample parking available. Pit toilet available at the Table Rock Trailhead.
Views of a Patchwork Forests
Ironically, our wilderness hike started out on an old road that maybe 30 years ago was used to haul away timber. So, even though our intention was to experience wilderness, we found ourselves face-to-face with industrial timber production.
The Table Rock Wilderness is a 6,028-acre swath of mostly hundred-year-old uncut forested land. It was established in the 1980s as part of an effort to protect what little remained of unharvested forests in western Oregon. However, the Table Rock wilderness is almost completely surrounded by industrial timberlands, both public and private. Therefore, when views opened up along the trail, we found ourselves looking down on a patchwork pattern of forest in various stages of production.
Beyond the Horizon
Looking beyond the horizon, the patchwork of Oregon’s forests become even more complicated. Almost half of Oregon is forested. About a ⅓ of is owned by private forest owners, while the remaining ⅔ are public forests, managed by government agencies like the BLM and USFS. A majority of the timber harvest is done on private land, where economics is often the primary driving factor. While the remaining timber harvest on public lands works to meet multiple objectives.
The BLM’s Northwest Oregon District alone manages about 800,000 acres of land, much of it secondary growth from clear-cuts in the mid-1900s. A time period when timber production and economic gains was the priority. Now, our public lands are managed for multiple uses, including timber production, but with ecological and social considerations to balance. To accomplish these goals which may seem to be in conflict with one another, much of the land that the BLM manages are held in reserve, including the Table Rock Wilderness.
In other words, much of Oregon’s forests are the product of out-of-date forest management practices that don’t necessarily jive with our current goals.
Modifying the Land
Pretty quickly, Jonas and I made our way off the road and deep into the douglas-fir/western hemlock forest. “Look at this chunk of land,” said Jonas, “diversity of species and canopy layers, appropriate spacing and correct vegetation. It doesn’t need anything.” The hydrology of this forest is functional. However, “most of the lands [in western Oregon] don’t look like this.” Most of our forest lands have been modified at one point or another. And modification changes the hydrology.
Jonas explained—”Whatever and however you modify the landscape there are going to be consequences.” For example, when a forest is clearcut, the amount of water that trees transport from the soil to the air, a process called transpiration, will decrease, as there are fewer trees to do the work.
However, if that same area becomes overgrown with lots of shrubs, or is replanted at a high density with trees, transpiration will increase again.
Each of these modifications changes the amount of water in the system which may lead to problems. For example, too much water added to the system when transpiration decreases may result in more runoff, higher stream flows, and erosion. Too little water and you may be looking at a dry streambed.
“It’s this balance of modifying the landscape to accommodate different objectives,” said Jonas, which makes his work fun.
Quality and Quantity
So when we are talking about changing the hydrology, what does that really mean?
I asked Jonas how he defined hydrology. He said, “The grade school answer is it is the study of water.” But, he added, hydrology can really be “broken down into two measurements—water quality and water quantity.” If water quality and quantity are good, then you are looking at a healthy system. However, in a modified forest, maintaining water quality and quantity can be a challenge.
Clean, Clear Water
According to Jonas, when it comes to water quality in a modified forest ecosystem, there are two factors that should always be considered in order to ensure good water quality.
The first is turbidity. Turbidity is the cloudiness of the water. In most forested ecosystems, the turbidity should be low most of the time—that is the natural state of a forest stream unless there is a rainstorm or snowmelt which naturally induces erosion and thereby increases turbidity. However, any human activity that disturbs the soil, like building roads or harvesting timber, can also mobilize sediment so that it may enter a body of water. This is a huge problem especially for aquatic organisms— it can clog fish gills and smother eggs; reduces stream visibility; and it can absorb heat. It can also make drinking water treatment more difficult.
Second is the water temperature. Most rivers in Oregon are inhabited by cold-water adapted species. However, with climate change, early snowpack melt, and the removal of forest from along rivers or streams, high water temperatures are becoming a more frequent problem. High temperatures are problematic because they can reduce the amount of dissolved oxygen a stream can hold. Warm temperatures can also lead to the growth of algae. Algae can throw the ecosystem off balance by reducing oxygen concentration as they decompose, as well as producing cytotoxins.
Keeping it Clean
However, Jonas explained, proper management can help mitigate turbidity and temperature problems. For example, maintaining a vegetative corridor along rivers and streams can provide shade that prevents water from heating up, as well as help filter out sediments. According to Jonas, the primary shade zone is about 85 ft—this is where 95% of shading occurs. These “riparian areas or buffers” are prescribed by the fish biologists and hydrologists and, in the case of BLM land, a 120 feet buffer is maintained on perennial streams where stream temperature is a concern just to be on the safe side.
In addition, to reduce the risk of damage from road construction, road use, and road work, waterbars can be placed along logging roads at regular intervals. These redirect water and sediments into the forest where it can settle out, rather than allowing it to flow directly to the stream. Jonas pointed out one of these waterbars on the road we walked in on.
Too much or Too Little of a Good thing
On the water quantity side of things, the discharge, or rate, of freshwater flowing through an area is important. Or in the case of a lake, the volume of water. And since most of the water Oregonians consume comes from forested land, modifications to forestland that changes the amount of discharge of a stream is not acceptable.
Some of the mitigation measures used to reduce pollution can also help with efforts to protect water availability. For example, directing water flowing in ditches toward the forest (as opposed to directly into the stream) can help slow its flow. A good riparian area can do the same thing. However, much of BLM land has been managed since the 1930s with a goal of intensive timber production, so they are stocked at levels that may be too dense for balanced water quantity. Remember too many trees can mean less water available to the system.
Hard Decisions
As the focus of the BLM has shifted more towards a balance between resource protection and resource production in recent years, Jonas says, “The struggle is always there to balance the economic, the ecological, and the social.” Sometimes you have to make management decisions that aren’t popular, like thinning a riparian area, in order to reduce transpiration and bring the hydrology into balance. And though it would be nice to leave things alone and let cycles restore on their own, it takes a lot of time.
“We also have threatened and endangered species—fish, owls, you name it—and their survival depends on a healthy functional riparian area. The question I would ask is, ‘Can they wait two to three hundred years?’”
A Spring!
Early on in our hike, Jonas and I found ourselves startled by a rare find—a spring right in the middle of the trail! Coldwater was bubbling right up from the ground! Jonas pointed out that the geology around us is responsible for the formation of a spring.
Geology Brief
The Table Rock Wilderness has a volcanic geological history. The basement rock in the area is a volcanic rock called andesite, probably remnants of an old stratovolcano that existed 17-10 million years ago. Layered on top of the andesite, is a different type of volcanic rock called basalt. The basalt probably formed from lava that flowed into the area and cooled about 4 million years ago from a nearby Cascade volcanic eruption.
At one point during the hike, you skirt around basalt pillars—called columnar basalt—that makeup Table Rock’s summit. One of the many cool geological sights on the hike.
Hidden Water
All that being said, it is the volcanic nature of the Table Rock Wilderness that influences a part of hydrology that is often overlooked—groundwater. About ⅓ of water on Earth does not flow on the surface but exists underground. In comparison, surface water—lakes, rivers, etc—makes up only about 1% of all freshwater.
In the case of the Table Rock Wilderness, much of the water that lands in the forest will infiltrate into the ground and recharge “deep, deep basaltic aquifers”—huge groundwater storage zones.
Because basalts tend to fracture, Basalt rock aquifers tend to be very permeable and porous making them ideal for supplying water to springs and seeps.
“Springs regulate themselves and fluctuate very little,” said Jonas. The Table Rock Wilderness hydrological system is in balance in part because “water that enters the aquifer is equal to the water that leaves.” He went on, “Shallow aquifers are more prone to weather and drought. But that is not what we got here. Here we are 4,000 feet up on a basalt mountain! If there is that much water coming out of the ground, that amount is going to fluctuate very little throughout the year.”
Let it Snow
After a couple of miles of hiking in the woods, the trail opens up to views of Table Rock. It was here—while hiking through a rockfall that supposedly is inhabited with Pika—I saw a glimmer of white at the base of table rock. It was snow!
Water in its many solid forms makes up about 2/3rds of freshwater on the planet—by far the biggest chunk. O.K. so most of that is probably accounted for in the polar regions. But still, glaciers and snowpack are incredibly important water reservoirs in the Pacific Northwest.
According to Jonas, snow is still the largest reservoir of water in Oregon. And in the Table Rock Wilderness, this is also the case. Though most (well, basically all) of the snow had melted by the time we hit the trail, it was still working its way through the hydrological system underground, ultimately bubbling up to the surface through springs and seeps.
Looking out to my right from the base of Table Rock, I could also see Mount Hood in the distance. Similar to how Table Rock supplies water to its creeks, Mt. Hood and the rest of the Cascades, supply water to some of Oregon’s largest rivers and most populous areas. For example, the McKenzie River is a spring-fed system—supplied by a mountain snowpack that melted, infiltrated, and has been traveling underground for several years!
Wondering about Watersheds
After returning to the woods and circling Table Rock, Jonas and I eventually hit the switchbacks that take you to the top of the rock. Though Jonas opted to hang back, I had heard the views were too spectacular to miss, so I made the ascent alone.
It was worth it! Looking out across the landscape at the mountains, ridges, and valleys, was spectacular. It also brought me back to discussion Jonas and I had earlier regarding watersheds.
Anytime you are standing on the planet Earth, you are standing in a watershed. A watershed is simply an area of land that drains to a common body of water. For the Table Rock Wilderness this common body of water is the Molalla River.
A Drop at the Top
As Jonas described it—if you take a drop of water and place it on the top of Table Rock it will travel a number of different ways—it might travel to Image Creek to the north or Bull Creek to the south—but ultimately it will end up in the Molalla River. That is because the Table Rock Wilderness sits in the middle of the Molalla River Watershed. The Mollala River and Table Rock Wilderness are connected, even though the river never flows within the wilderness boundaries. This connection extends to the Willamette River as well. The Molalla River is the largest undammed tributary to the Willamette River.
So standing on the top of Table Rock, I was standing in the Mollala River Watershed, the Willamette River Watershed, and the Columbia River Watershed, as well as probably one or two smaller watersheds nested within.
Though I didn’t spill any water at the top (other than sweat), it was still fun to trace the journey of a drop in my mind. A practice I recommend trying next time you are on a ridge.
An Uncut Forest
After visiting the Table Rock summit, Jonas and I continued along the Saddle Trail and High Ridge Trail toward Rooster Rock. These trails led us back into the forest and through some gorgeous wildflower meadows.
Taking in all the unique features of the area, Mine and Jonas’ conversion came back to a topic we touched on earlier—change. Change is part of the cycle of a healthy functioning ecosystem. In fact, the Table Rock Wilderness formed following a forest fire about 100 years ago.
Things are Changing
But, Jonas asked, “What will it look like in 100 years? 200 years?” With climate change creating hotter, dryer conditions, will we see a shift away from the Douglas-fir/ Hemlock forest to one filled with Pine and Madrone? As wildfires become more frequent and severe, how will that change the dynamics of the landscape? And, perhaps most importantly, should we step in?
Wilderness areas are for the most part “untouched,” but with global crises like climate change and biodiversity loss, we need to start considering our impact on these untouched places, and whether or not we should do anything in response. “We need to acknowledge no management is management,” said Jonas.
Neither Jonas nor I had the answer, but we need to keep asking the question—How do we best protect our public lands?
Sweat Worthy
After several hours of sweating it out on the trail, Jonas and I followed the Rooster Rock Trail down to the trailhead where we had staged our return vehicle.
Overall, the hike was long and challenging, but the scenery was worth every bead of sweat. I definitely recommend hiking the Table Rock Wilderness. Just make sure you pack enough water!
Jonas Parker is a Hydrologist for the BLM Northwest Oregon District. He received his B.S. in Fisheries and Aquatic Science at Utah State University and Masters in Natural Resources Management from the University of Idaho.