"It is a soft green place where rain rules....." --Robert Michael Pyle
Patty and I visited Rainbow Falls State Park as a picnic stop on our way home from Cape Disappointment State Park in May 2018. The park, well loved by area residents, was busy with extended-family picnics, clanging horseshoes, a ball game, and a steady stream of family groups wending their way to and from the decidedly underwhelming 5 foot drop in the Chehalis River that forms Rainbow Falls.
This park, one of the older stalwarts in the system (facilities were built by CCC workers in 1935), was heavily impacted by flooding in December 2007 which tore out the access road bridge and a picturesque footbridge above the falls. The massive flood raised the Chehalis River more than 18 feet above flood
stage just upstream of the park (at which point the gauge was swept down the river), impacting hundreds of roads, bridges, homes and businesses, and closing I-5 for several days, diverting more than 60,000 vehicles each day. In response, the Washington Legislature created the Office of Chehalis Basin within the Department of Ecology to lead implementation of the Chehalis Basin Strategy. The Strategy is a detailed set of actions to improve and restore aquatic species habitats, ecosystem processes, and populations of aquatic and semi-aquatic species – while also creating flood and climate-resilient systems that support the human needs in the Basin, the second largest drainage basin in the state.
Rainbow Falls State Park is a 139 acre oasis of mature to old-growth forest in a part of the state that has seen the most intensive industrial forest management-- 230,972 acres (about 14% of the forestland) of the Chehalis River Basin was clearcut between 2002 and 2007.
Transpiration by the trees in a forested area uses up water during the summer months, depleting the soil moisture reservoir. November rain must recharge the soil moisture before draining to streams. In contrast, a clearcut area has higher soil moisture levels and a lower capacity to store incoming precipitation because water has not been removed by transpiration. More of the rain falling on the clearcut area passes directly into streams and rivers. In real numbers, a single mature Douglas fir at Rainbow Falls transports 40-80 gallons of water from its roots up through the sapwood to the stomata on its needles on a typical summer day. With the trees removed on nearly 40,000 acres of the Chehalis Basin each year, over 21.6 billion additional gallons of water (for comparison--Seattle's Lake Union contains about 6.5 billion gallons) could compound the effects of flooding. In addition, forestland that has been clearcut is up to five times more likely to have landslides than forested ground, and the landslides transport logs and other debris then carried by the flooding river. Amplified over such a large area as the Chehalis Basin, the results can be devastating to communities located on the receiving floodplain.
On December 3, 2007 storms brought up to 20" of rainfall to the headwaters of the Chehalis River in the Willapa Hills, triggering landslides and debris flows. Temporary debris dams eventually gave way unleashing a wall of water up to 18' high that ripped out the bridges in the park and along the Willapa Hills State Park Trail. Rushing waters swelled the flow at the gaging station just upstream from Rainbow
Falls to 63,100 cfs (the previous record in a 1996 flood was 28,900 cfs). By 2:30 am the local fire department began evacuating residents near the river, many of whom lost homes, dairy cows, horses, sheep and pets to the raging waters. 55 homes were swept into the river. As flooding overwhelmed areas that had no history of flooding, emergency crews continued water and air rescue operations for 5 days, eventually completing more than 500 rescue missions. Stranded motorists and truck operators were air-lifted from submerged vehicles. As waters slowly receded, fire departments were kept busy extinguishing barn fires as wet hay inside began to smoke from spontaneous combustion. Ultimately, 3,000 homes sustained damage--1,000 beyond repair. Nearly $900 million in damages were recorded.
As with wildland fire, some of the root causes of flood events like this one are traceable to past actions and decisions. 1) As noted above, the historic intensity of logging activity in the basin has exacerbated flooding effects. 2) Previous flood-control and development actually increased the potential for damage by eliminating natural mitigating elements such as off-channel wetland areas and in-stream beaver ponds; and 3) political unwillingness to restrict development in the known path of floodwaters placed many residents and businesses in harms way. In light of climate change models that predict increasing storm intensity we can expect more such impacts in the future.
The same wetness that initiates the potential for catastrophic flooding also makes the Willapa Hills and Rainbow Falls State Park an excellent habitat for amphibians, which along with salmon are a focus of the Chehalis Basin Aquatic Species Restoration Plan. By definition, amphibians are dependent on wetness for their survival, so one would certainly expect them to be at home in this damp corner of the state. The protected forests of the park harbor at least six species of newts and salamanders. Most are infrequently seen in their hidden dwelling places, but the more numerous rough-skinned newt (pictured on ferns at the top of this blog post) is often encountered, especially during the late fall migration to quiet water breeding areas. Females deposit eggs onto stems and leaves of submerged plants and larvae emerge about a month later. Most larvae overwinter in the place they hatched, scraping food off plants and rocks until their month-long metamorphosis occurs the following summer and they disperse to subterranean habitats such as decaying logs and rocky crevices. The juveniles take 4-5 years to reach sexual maturity, usually breeding every other year through an adult life span that reaches 12 years or more.
When threatened by a predator, rough-skinned newts display a body posture called the unken reflex. Eyes are closed, limbs extend laterally, the head is raised vertically, the back is depressed, and the tail is raised forward over the body revealing their bright orange ventral coloration, a warning to predators-- "don't even think of eating me!." The newt, with the assistance of a symbiotic bacteria, releases a neurotoxin called tetrodotoxin (TTX), the same poison found in pufferfish. This toxin targets sodium channels in nerve cells and blocks electrical signals necessary for conducting nerve impulses. The inhibition of firing action induces paralysis and death by asphyxiation. In 1981, a 29-year-old man in Coos Bay, OR ate a single 8-inch rough-skinned newt on a dare. Within minutes, he experienced numbness and prickling and tingling of his lips and tongue, followed by facial and extremity numbness and sensations of lightness or floating. Declining transport to a hospital, he soon succumbed to increasing paralysis, first in the extremities, then in the rest of his body, and finally in the respiratory muscles causing his death. There is no antidote for TTX.
The documentation of the newt's toxicity came about by an curious path from a deadly hunting trip to an advancement in evolutionary biology. Biology student "Butch" Brodie Jr. heard a story of three Oregon hunters who failed to return from a weekend trip. Police found them dead at their campsite with no signs of violence or struggle. They also found a fourth body: a rough-skinned newt that had been accidentally boiled with the water used to make a pot of coffee. Brodie set out to investigate the hypothesis that the newt had poisoned the men. After trapping newts in buckets, he ground their skin with a mortar and pestle, mixed it with water, and injected or force-fed a variety of animals with different concentrations. His first subject, a house mouse, died in his hands before he could even put it back in its cage, and he found that even just a tiny amount of newt skin—0.0002 ml—could kill a mouse within 10 minutes. Brodie's son Edmund who grew up capturing newts for his father's research, became a biology professor as well and continued the investigations. His father's discovery that garter snakes were resistant to TTX poisoning led to extensive research revealing that the degree of tetrodotoxin resistance in populations of garter snakes is roughly correlated with the degree of toxicity of co-occurring populations of rough-skinned newts. Newt toxicity varies greatly by region, with some of the most toxic found in the Willapa Hills area. Detailed genetic testing ultimately revealed an evolutionary arms race between rough-skinned newts and garter snakes.
There are many unsung heroes in the unfolding process of understanding and responding to the accumulating effects of modern industrial life on our planet. The Chehalis Basin initiative is a bold and hopeful process toward restoration and reconciliation in a severely injured landscape. A partnership of leaders, biologists, engineers and naturalists from public agencies, the Quinault and Chehalis tribes, and volunteers labor across the basin to gather data that can be used to set priorities for the restoration of the healthy flow of water through this rich place. I hope that the successes, large and small, that are achieved here will help inspire a mobilization to meet humanity's looming challenge with scientific grounding, ingenuity and creativity, in ways that strengthen our understanding and connections to each other.
--David
Photo of kayaker in floodwaters courtesy Lewis County Emergency Management
Photo of old footbridge courtesy NWPlaces2C.com