Drops
Of
Water
Issue 26 January 1999
The first people to find errors in spelling or word structure receive a free map of the Chehalis watershed. Send us an e-mail note telling us about the error.
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Issue 26 January 1999 |
This newsletter appears monthly in 45,000 households throughout the watershed. Printing is done by The Chronicle, and distribution is by the Chronicle, the Olympia Daily Olympian, the Tenino Independent, the Rochester Sun News and the Aberdeen Daily World. This is an early edition available only to WWW users. Please send us your feedback.
The first people to find errors in spelling or word structure receive a free map of the Chehalis watershed. Send us an e-mail note telling us about the error. |
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At a December 4 meeting of the Chehalis Basin Partnership, Mayor Bob Spahr of Chehalis was elected chair. Mayor Spahr succeeds Thurston County Commissioner Dick Nichols, who guided the Partnership through its early organizing stages.
Chehalis Tribe Environmental Resources Manager Dr. C.S. Sodhi was elected Vice Chair.
In closing remarks, Commissioner Nichols said that the Partnership was on the verge of putting together an organization that is really effective. He pointed out that the world is an interconnected puzzle, and the reality is that this watershed works in a complex way. What is done on the flooding issue, foremost in everyone's mind, will affect the entire Basin.
(Partnership attendees drove through water over Anderson Road to attend the meeting at the Casino.)
Next Steps
Nichols summarized a round table discussion by saying that the next steps for the Partnership are to develop further an organizational framework, focus on the activities included in the ESB 2514 watershed management grant, ensure that information sharing is well-integrated in Partnership activities, and include a public outreach emphasis.
Sue Mauermann of the Department of Ecology presented Commissioner Nichols with a framed photo of a Black River site in appreciation for his leadership.
Partners not signed up
The Partnership still lacks several signatures on the Intergovernmental Agreement. Brian Walsh, DOE, reported that two water districts, the City of Aberdeen, and Quinault Nation will sign in the near future. Until the signatures are obtained, the Partnership does not quite exist.
As yet, Mason and Grays Harbor counties have not appointed citizen representatives. Lewis county citizen Ed Moerke and Thurston County citizen Margaret Rader were at the table for the December 4th meeting.
Flood update
In a regular update, Commissioner Richard Graham of Lewis County reported on Lewis County's flood hazard reduction project. A two page report was submitted to the legislature on December 3 outlining how the $600,000 provided by the state has been spent. A report has also been submitted by Pacific International Engineering (PIE) and is being reviewed by the Technical Committee but is not available for public inspection. The Technical Committee is chaired by Jerry Alb of the Washington Department of Transportation (WDOT) and includes representatives from a number of federal and state agencies and local jurisdictions.
Beginning December 16 in Centralia, a series of public meetings will present alternatives for reducing flooding in the Centralia Chehalis area. In addition to the December 16 meeting, community meetings will be scheduled in January in Bucoda, in Grays Harbor, with the Chehalis Tribal community, and in Chehalis. Lewis County has established an 800 number for questions about the flood reduction project: 1-800-519-1124.
Chair Dick Nichols added that it was fair to say that the draft interim report had drawn some criticism from the Department of Transformation and some members of Technical Committee. He said there is a kind of dance going on between the need to get something done about flooding and the need to consider all the viable alternatives. Graham also commented that "This is not a done deal," and an executive committee of signers of the interlocal agreement, including Lewis, Grays Harbor, and Thurston counties and the cities of Centralia and Chehalis, will make the final decision.
PeEll Mayor Resigns
Consideration of the flooding issue by the CBP was one of the reasons that led Mayor Penberth of PeEll to resign from the Partnership for the second time.
He pointed out that the Partnership is straying from the tasks required by ESB 2514. He also expressed his continuing frustration that funds can't be funneled directly from the state agencies to fix his city's water problems.
The next meeting of the CBP will be January 22, 9 am, at the Casino near Oakville.
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A free public meeting for landowners on the South Fork of the Chehalis River will be held at 7 pm Wednesday, January 13 at Baw Faw Grange, Boistfort Road. The meeting will deal with water quality and salmon.
Others interested in these topics are also welcome to attend.
Representatives from a number of agencies and organizations will be on hand to answer questions about how to improve water quality and about opportunities for assistance with streamside restoration projects such as fencing.
Specialists from the state Department of Ecology, the Lewis Conservation District, the U.S. Fish and Wildlife Service, the W.S.U. Extension Service, the National Marine Fisheries Service, the Chehalis River Council, the Chehalis Tribe, and Weyerhaeuser Corporation will be available.
Also attending will be landowners in the Chehalis Basin who will describe their experiences with accepting grants for streamside restoration.
Meeting topics include:
The water quality improvement drive in the South Fork.
Salmon habitat restoration in Stillman Creek (Mill Creek).
How endangered species listings may affect you.
Who has money to help you fix problems.
What laws affect you and how you can avoid problems with your livestock.
Why the Department of Ecology is visiting livestock farms.
Farm plans and pasture management.
The livestock and water quality connection.
Low-cost fencing.
How to protect your streams and creeks for fishing, swimming, and stock watering.
For more information contact Ecology's Eric Schlorff at 407-6287.
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What's the news on flood maps? Lot's of talk is going around about this map or that map. Last year, December of 1997, to find out the answers we went to FEMA and the Corps (U.S. Army Corps of Engineers). This year, December, 1998 - we find no maps have been updated!
FEMA maintains a Community Status Book. It is updated daily. It shows separate maps for each county and city along the river. The maps only show the extent of the 100- and 500-year flood plains and elevations of the 100-year flood. Elevations for the 10-, 50-, and 500-year floods can be obtained from the flood profiles in the Flood Insurance Study reports associated with the maps. Here are the current map dates and communities.
07/16/84 Aberdeen
09/02/81 Bucoda
06/01/82 Centralia
05/01/80 Chehalis
11/03/82 Cosmopolis
08/19/85 Elma
08/16/82 McCleary
10/13/81 Montesano
03/02/82 Morton
06/19/85 Oakville
03/01/78 Ocean Shores
03/04/80 Pe Ell
07/16/79 Raymond
02/16/90 rural Grays Harbor
12/15/81 rural Lewis
05/17/88 rural Mason
09/27/85 rural Pacific
12/01/82 rural Thurston
12/01/83 Shelton
11/15/79 South Bend
06/04/80 Tenino
11/05/80 Toledo
09/14/79 Vader
05/05/81 Westport
09/14/79 Winlock
The existing FEMA maps are based on studies done up to 25 years ago. Many significant floods have occurred since then. After the 1996 flood, FEMA asked the Corps to update the Chehalis River frequency curves at Centralia and Chehalis and determine the effect on the 100-year flood elevations along I-5 where it was underwater during the 1996 flood. The new curves indicate a significant increase in the 100-year flood such that the existing FEMA maps underestimate the 100-year flood elevations from 1-2 feet at Chehalis. Similar changes are likely elsewhere along the river. Based on this information FEMA asked the Corps to do a revised Flood Insurance Study for the following streams in Lewis County:
1) Chehalis Grand Mound - Adna for 21 miles 2) Newaukum mouth - Newaukum Bridge for 12 miles and 3) Skookumchuck Mouth - Bucoda for 14 miles
It is indeed unfortunate that newer maps are still not available. If you need flood insurance or if you plan construction activities in the floodplain you will still have to deal with maps as much as 25 years old.
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Sticking My Chin Out
Dave Palmer, Chehalis River Council
The residents, homeowners, home buyers, developers and permit writers in the Chehalis Watershed face serious dilemmas.
Flood Maps
Elsewhere there is an article which summarizes the date the last official flood maps were created.
If you are a home owner or home buyer the maps can help you. Wouldn't you like to know if you are in a floodplain? The only recognized authority is the Flood Insurance Rate Map.
Are you a builder? Is your raw land inside or outside of a flood area? Again, the only recognized authority is the Flood Insurance Rate Map.
If you work in the permitting department of a city or a county wouldn't it be nice to know which regulations apply to construction permit in front of you?
Given that accurate maps are important how can they do business today?
The answer is simple. They use the existing maps and regulations to make decisions which might be right or wrong.
Regulations
A number of communites throughout the state make their city or county codes available on the internet.
Just to see how buyers, builders, developers and permit writers are impacted by regulations, the flood plain regulations from 2 counties and 2 cities were reviewed.
Are they the same? NO.
If you live in one of the cities you face only 177 words of regulations, but in the other city you'd have to meet over 3,600 words of regulations.
In each county you would see similar regulations. Each of them has over 7,700 words devoted to floodplain activity, but the regulatory authorities use different definitions:
In county A: ''Floodway' means the portion of the floodplain consisting of the stream channel and over-bank areas capable of conveying a selected flood discharge and keeping it within designated heights and velocities."
In county B: "Floodway The channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than one foot."
And in City A there is a "Regulatory Floodway: The channel of a stream plus any adjacent flood plain areas that must be kept free of encroachment so that the 100-year flood discharge can be conveyed without increasing the base flood elevation more than a specified amount."
Thurston, Lewis and Grays Harbor county were not sampled. Their regulations are not online for internet public access.
The Dilemma
We have poorly written rules, yet they define what is permitted. The rules are operating on maps which are obsolete. To complicate the issue there can be rules in one county which would be in conflict with another county. There can be permits written in one city that would be challenged in a city downstream.
In my opinion we need a cooperative effort among the cities (14) and the 3 major county governments. We need to define and implement watershed wide consistent flood regulations based on current flood insurance rate maps which protect the current residents.
What's your opinion?
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Editors note: This month the focus is on the Upper Chehalis Each month we will publish a watershed description from the 1992 Chehalis River Basin Action Plan.
We are looking for serious volunteers who can assist the Chehalis River Council bring this section of the report up to date. Please contact us if you are interested.
Topography
The Upper Chehalis subbasin above the Newaukum River drains about 450 square miles. The watershed is located in Lewis, Pacific and Cowlitz Counties. The main tributaries include the Main Fork, the South Fork, Elk Creek and Stillman Creek.
The Chehalis River originates in the Willapa Hills which are part of the Coast Range. Generally the elevation is below 2400 feet with Baw Faw Peak being the highest elevation at 3110 feet. The river valley on the main fork broadens out below PeEll and at the Lewis County/Cowlitz County line on the South Fork. The elevation at Centralia is 185 feet.
The Chehalis River is the principal river in this subarea. Its headwaters are south of PeEll. The river flows northeast toward Chehalis-Centralia before turning northwest and eventually emptying into Grays Harbor. The mean annual discharge of the upper Chehalis River at the USGS gaging station near Doty is 575.4 cfs. A peak flow of 22,800 cfs was recorded here on January 20, 1972, however, these records extend only to 1979, and do not reflect the flows during the flood of January, 1990 which were the highest on record. A low mean flow recorded for the Chehalis River at this station was 18 cfs on one day in 1953
There are four major geological formations in the Upper Chehalis subbasin. They are; 1) alluvial deposits of the Quaternary Age, 2) alluvial terrace deposits of the late Tertiary to Quaternary Age, 3) volcanic flows and interbeds of the Tertiary Age, and 4) sedimentary rocks of the Tertiary Age.
The uplands of the basin are generally made up of rocks of the Tertiary Age, predominantly volcanic flow, and fine-grained sedimentary rock such as shale, siltstone and sandstone. Deposits of Tertiary Age normally yield only small quantities of groundwater and often this water is unsuitable for normal uses due to its high mineral content. Dissolved-solid concentrations greater than 500mg/1 and hardness as CaCO3 greater than 120mg/1 are not unusual in the older rocks.
Alluvial deposits of Quaternary Age occur mainly in the valley of the Upper Chehalis River subbasin. They have a thickness which ranges from a few feet to more than 55 feet in the area of the Chehalis Indian Reservation. These unconsolidated materials consist of silt, sand and clay in the upper part, and sand and gravel in the basal portion. The porosity and permeability are not clearly known since most wells obtaining water from this geologic unit seldom pump in excess of 50 gals/min. However, yields of this size are obtained with no draw down indicating a moderate to high porosity and permeability.
The soils have developed over a long period of time and therefore have deeply weathered parent materials and heavy textures. In spite of this, the majority have structures that can accommodate the penetration of water, air, and roots. Because they are leached and slightly acidic, their organic-matter content is moderately high, but supplies of available nitrogen and phosphorus are deficient.
Climate
The Upper Chehalis subbasin has mild, rainy winters, and warm, dry summers. The upper basin is largely rain-fed with precipitation levels which range from 40 inches at Centralia to 120 inches in the Willapa Hills. About 85 percent of this annual precipitation occurs during the periods from October to April. Prolonged periods of drought occur occasionally in the summer with no rainfall for from 30 to 60 days. Snowfall at the higher elevations occurs during the winter and can exceed 24 inches.
Water use
There are small diversions for irrigation and domestic use. A community water system serving Adna, Boistfort, and Curtis, uses Stillman Creek as its source. Pe Ell obtains its municipal water from Lester, Grim, and Mahaffey Creeks; tributaries of the Chehalis River located on Weyerhaeuser timber holdings. Doty and Dryad receive their water from wells, but Elk Creek is being investigated as a source for a common municipal water system for these two communities.
Existing Land Use Patterns
Land use within the Upper Chehalis River subbasin is primarily forestry agriculture, and residential. Forest lands are located primarily on the upland areas. Agricultural lands are concentrated in the river valleys where they have widened out. The residential areas are concentrated along Highway 6 and the small communities of Adna, Boistfort, Dryad, Doty and PeEll.
The forest products industry serves an important economic role in the Upper Chehalis subbasin. There is a logging operation located in the town of PeEll employing over 100 people. A transmission and distribution pole manufacturing facility located at Curtis employs over 30 people. There are many Christmas Tree plantations located in the subbasin. Minor forest products such as , ferns and fir bows are also harvested throughout the subbasin.
Agricultural also serves an important role in the economy, The most intensive farming is done on the fertile alluvial floodlands. Field crops, poultry, beef cattle and dairy cattle are important elements to the agricultural section. The farms in the subbasin are following the national trends of increasing in acreage while decreasing in number.
Biological Resources
The Upper Chehalis subbasin is an important spawning area for anadromous fish, Chinook, coho (silver) and chum salmon, and steelhead and sea-run cutthroat trout. The Upper Chehalis subbasin and its tributaries spawn many of the fish which form the basis for recreation and for a sport and commercial fishing industry on the coast. Resident cutthroat and rainbow trout are other sport fish native to the Basin. Sport angling for these species is a popular leisure activity in the Upper Chehalis subbasin.
Wildlife resources of the Upper Chehalis River include, big game (blacktailed deer, black bear and elk), game birds (pheasant, grouse and pigeons), fur animals (beavers, minks, muskrats and river otters), and various waterfowl. Considerable hunting is practiced in the Upper Chehalis River. Seasonally flooded lands provide habitat for some water fowl. The Upper Chehalis subbasin also lies under the same principal migratory bird routes including Canada geese.
The Upper Chehalis River Basin supports a dense, natural vegetation cover as a result of the prevailing maritime climate. Forests occupy about 90 percent of the area. The species include Douglas fir, western hemlock, noble fir, silver fir, western red cedar, western re alder, sitka spruce, black cottonwood and big leaf maple. The understory includes evergreen blackberry, spine a. wild rose, skunk cabbage, salal, Oregon grape, vine maple and a variety of ferns. Except for a few, minor, scattered stands, all the natural mature and old growth stands have been logged and only wild second growth stands and managed plantations remain.
The dominant species is Douglas fir accounting for 70 percent of the volume by species. Western red alder, sitka spruce, western red cedar and cottonwood are found in areas of poorly drained mineral soils. The river bottoms, under natural conditions, are generally occupied by a variety of herbaceous and wood vegetation including scattered stands of hardwoods and second growth coniferous timber.
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Diane Schwickerath, Board Member, Grays Harbor Audubon Society
Grays Harbor Audubon Society (GHAS) is a chapter of the National Audubon Society. GHAS's membership is made up of 200 families in and around Grays Harbor County. The mission of GHAS is "to seek a sustainable balance between human activity and the needs of the environment; and to promote enjoyment of birds and the natural world". To this end, we have undertaken a very exciting project in the lower Chehalis watershed that we call the Humptulips Wetlands Project.
Encouraged by having purchased a 20 acre wetland and an 8 acre saltmarsh outside of Westport, we launched an ambitious project in the spring of 1998 to purchase and protect 400 acres of prime wetlands in the lower Humptulips watershed. The primary purpose of our acquisitions so far is to preserve and protect these properties in perpetuity as wildlife habitat. At this writing (12/98) we have already purchased 86 acres in the project and will purchase another 86 acres within a month! We have done grant writing, received donations from our membership and received a substantial anonymous donation.
This project contains many different types of wetland habitats, including fresh water marsh, sloughs, bay frontage and tidally influenced surge plain-like wetlands, plus many acres of slough branches. Two of our member biologists see this area as an important fish habitat zone. In addition to many bird species that use this area year round, Black Bear are also resident.
One parcel in the project (100 acres) has been logged and we have as yet, been unable to purchase it. In and of itself, it does contain some wonderful wetland habitat, lots of birds, an important slough and has excellent restoration possibilities. It could use some help to make it more "salmon friendly". We are willing to undertake a restoration project here and work to get the grant monies needed for that type of effort, but this parcel has been the most difficult to get funders excited about. We continue to try to find the money to purchase this parcel. It is also the one parcel in this project that would lend itself to some human activity like birding and nature walks. It is extremely important to give people opportunities for nature appreciation in appropriate places, and this could be one of those.
All habitat lands owned by GHAS will be secured with a conservation easement so that no matter what ever happens to our Audubon Chapter, these lands will never be developed and will remain set aside for wildlife habitat in perpetuity. If you agree this is an important venture, please consider joining Grays Harbor Audubon Society or making a donation to the Humptulips Wetlands Project. For more information you can write to Grays Harbor Audubon Society, PO Box 444, Montesano, WA 98563, or call 360 495-3101.
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The Chehalis Sub-Zone of the Lewis County Flood Control Zone District Citizens Advisory Committee held a town meeting at Boistfort on December 1.
Boistfort: This was the first in a series of meetings being held in rural Lewis County. The purpose is to provide an opportunity for citizens to gain information on flooding issues in the County. The committee wants insight on the flooding problems effecting people in their neighborhoods, and wants to share their ideas on solving these flooding problems and those of Chehalis and Centralia.
Though the weather made it difficult for most, there were several stalwart citizens who attended, along with Lewis County Commissioner Russ Wigley, Forest Brooks of the Army Corp of Engineers, Shirley Kook, County Engineer and several members of the committee (Phil McBride, Doug Wisner and Ilona Petersen).
A presentation of the committee's project of developing a plan for abating future flooding in rural Lewis County was presented. The committee is in the process of forming guidelines for use in selecting, prioritizing and funding flood reduction projects. It was emphasized that public input is essential in establishing these guidelines and that it is necessary that government officials are made aware of what the citizens of the County desire by way of solutions and what they are willing to do to fund these solutions.
An informative discussion of flooding problems of the Boistfort/Curtis area followed the presentation, along with questions and answers regarding Pacific International Engineering's (PIE) proposed alternatives.
Other meetings are being planned for Adna, Napavine, the Skookumchuck area and other areas of Lewis County. Background
The committee envisions developing a manual as a tool to help County staff in their decision making process. It will go along with the Comprehensive Flood Hazard Management Plan for Lewis County. That comprehensive plan was developed by government agencies in 1992.
According to a member of the committee, the plan is in the beginning stages. They have gone as far as defining the purpose and goals and have determined an outlined of the criteria for project selection.
The committee has not formulated any definitions or specifics and wants the public to help them by turning in their questionnaires and through their attendance and participation at other public meetings.
The current alternatives being studied now by PIE and County staff are site specific (Chehalis and Centralia). The PIE scope of work only includes alleviating flooding in those areas. The committee understands that there are other flooding problems in the County and want to ensure that these problems are addressed by County staff. They understand that in order to gain support for the larger projects, the problems of the rural county need to be considered and acted upon.
Editor's note: This article is related to the survey form, and general information elsewhere in this edition.
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Lewis County Commissioners created a Flood Control Zone District in March 1997. Later, the Citizen Advisory Committee (CAC) was appointed to advise the Commissioners on flood related issues.
The CAC's purpose is to familiarize itself with all flood reduction issues within the county, to encourage public participation in the public forum sessions of their meetings; and to identify flooding problem areas and solutions using the help and input of the public as much as possible.
Our goal is to consider your comments in a polite and reasonable way, and as much as possible, include the general intent of those comments in the recommendations we forward to the County Commissioners.
Toward this end, the CAC is working on a citizen's guide to the "Lewis County Flood Damage Reduction Plan". This document will provide guidelines to County public officials to use in their efforts to select, evaluate, and prioritize flood damage reduction measures.
In order to hear your concerns and contribute to our work, we would like you to take a moment to complete the following survey.
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Your comments are important to the Chehalis Sub Zone Committee.
In order to hear your concerns, we would like you to take a moment to complete the following survey.
(OPTIONAL)
NAME:
ADDRESS:
My Workplace is in:
Centralia Chehalis Rural, Chehalis Basin
Rural, Cowlitz Basin Other/Don't Know
Flooding Problems Specific to Your Place of Residence or Business:
What specific areas of flooding affect you most?
What do you believe are the factor s aggravating this problem (i.e., development, roads, clear cutting, more impervious surfaces)?
What are your ideas to solve or lessen the problem?
Flooding Problems of Lewis County in General:
What percentage of the current flooding problems in Lewis County do you think can be solved?
0-24% 25-49% 50-74% 75-100%
What flood mitigation measures do you find most desirable? Rate the following from 1 (best) to 6 (least desirable).
__ Structural mitigation measures (i.e., dam modification, overbank excavation) using federal or state funding.
__ Structural mitigation measures using local tax funding.
__ Restrictions on landuse to lessen flood damage.
__ Purchasing flood easements.
__ Restrictions on filling and development in the flood plain.
__ Other. Please identify, if possible.
What should be taken into consideration when designing flood mitigation projects? Please rate using 1 to 6.
__ Aesthetics
__ Recreational Value
__ Maintenance
__ Environmental
__ Economic Development Opportunities
__ Cost
Please mail your completed survey to:
Chehalis Sub Zone Committee
c/o Shirley Kook, Senior Engineer
Lewis County Public Services
350 North Market Blvd.
Chehalis, WA 98532-2626
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Mike Kelly, U.S. Fish and wildlife Service
The Chehalis River Basin has a fascinating geology. Believe me, it really does. Sure, we don't have our own volcano like some of the other basins, but we do have ancient lava flows, strange glacial features, and important marine animal fossils.
Did you know that the oldest baleen whale ever discovered came from rocks right here in the Satsop River watershed? (Baleen whales are the kind that strain their food through plates in their mouths, like gray and humpback whales. This one is around 28 million years old!) You may have seen some of the beautifully preserved crab fossils that come from our area in museums and rock shops all over the country. They are preserved in very hard balls of mudstone called "concretions." These crabs are of a similar age to the whale fossil - 20 to 30 million years old, and they look like they could just crawl right out of the rock.
There are many other fossils, including shells and bones, in many parts of the Chehalis Basin. This is because large areas of land, stretching from the base of the Olympic Mountains and south past Pe Ell and Napavine, are made up of marine sedimentary deposits. These deposits of clay, silt, and sand were laid down on the sea floor between about 10 million and 50 million years ago. You can see these marine sedimentary rocks, in colors ranging from blue-grey to orange, exposed in road cuts and natural bluffs. The bluffs along Highway 12 at Porter are a good example.
These marine sediments are prone to landslides and surface erosion. (Have you ever had trouble making it into, or out of, Aberdeen? Slides on those bluffs have been a hazard to the highway for years.) Slides and surface erosion, whether natural or caused by human activities, can deliver large volumes of fine sediment to our streams.
Salmon and other fish can be harmed by excessive amounts of fine sediment in the water and in spawning gravel. Obviously salmon have coped with natural levels for tens of thousands of years, but our activities have caused some streams to receive much more than natural levels. A fish biologist needs to understand this local geology, and how it influences streams, in order to make the right decisions in designing salmon habitat restoration projects, and in recommending land use practices that help protect salmon.
Before the latest continental glacier receded some 10,000 years ago much of the northern USA was covered in ice thousands of feet thick. A lobe of the glacier extended through the Puget Sound region and into what is now Thurston County. The rivers that now flow into southern Puget Sound were blocked by the glacier and "backed up" into what is now the lower Chehalis River. Geologists say that during this glacial period the Chehalis flowed with a volume comparable to the flows of today's Columbia River. And you've probably seen the Mima Mounds. There is some debate about what caused them, but it is likely due to something associated with the melting glacier.
So, how does this glacier affect salmon in today's Chehalis River Basin? For one, the gravel deposited by the melting glacier makes ideal spawning gravel. In some streams, especially in the East Fork Satsop basin, gravel layers are so thick and porous that streams can naturally disappear and flow entirely underground. The porous nature of these gravel deposits allows water to percolate freely, creating many springs and upwelling water that are especially attractive to spawning chum salmon. These glacial outwash areas are also dotted with lakes and wetlands that make great habitat for juvenile coho and steelhead, as well as for cutthroat trout.
If you visit the Satsop River watershed during good stream flows, you may notice that the forks are different colors. The East Fork Satsop is often fairly clear while the West Fork Satsop is running muddy. Well, guess what. The West Fork flows largely through marine sedimentary rocks, and the East Fork flows through the clean glacial outwash gravels. A good place to observe this is in the area around Schafer State Park and the Middle Satsop Road.
OK, so we don't have our own volcano, and maybe this makes you happy, or maybe sad, or maybe you think it's a stupid thing to have feelings about at all. In any event, there are ancient lava flows, which originated both on land and undersea, exposed in several places in the Chehalis Basin. Along Highway 6 between Adna and Doty you can see outcrops of dark basalt rock that came from the same lava flows that created the Columbia Plateau.
There are also many exposures of the oceanic crust that forms the underlying bed of our region. These rocks, known as the Crescent Formation, were formed at volcanic fissures in the deep sea. They often have a pillowy look. The same "pillow basalt" is forming today in the mid-Pacific and is slowly creeping our direction. Oceanic crust usually gets pushed under the continent, melts, and is recycled. Our particular chunk of crust became dislodged and formed the foundation that we rest upon. The Doty Hills, Black Hills, Southern Olympics and much of the Willapa Hills are parts of this formation.
As I explained, knowledge of local geology can be helpful to fish biologists. It is also crucial knowledge for anyone building anything. And obviously rockhounds and fossil collectors would want to know this stuff too. But I think the best reason to know about our geology is that it is INTERESTING. If you are still awake, and want to know more, look for these references:
Roadside Geology of Washington, by Alt and Hyndman, from Mountain Press Publishing Company. (This book should be available in most larger book stores, and is a great companion to take on road trips.)
Geologic Map of Washington - Southwest Quadrant, from the Washington Department of Natural Resources (WDNR). (This is a large color map and chart that show and name the rock formations of the region. It is available from the WDNR Division of Geology and Earth Resources at the Natural Resource Building in Olympia. I think it costs about 10 bucks.)
Washington Geology magazine is a free quarterly journal also from the WDNR Division of Geology and Earth Resources. You can ask about this journal, maps and other publications by E-mail at geology@wadnr.gov Or visit their web site at http://www.wa.gov/dnr/htdocs/ger/ger.html
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This month the puzzle is difficult. But with school vacation you should have time to figure it out. We have taken sentences from some articles and rearraged the words. Your challenge is to reconstruct the original sentence. This might mean you have to read each story!
Agreement. Intergovernmental lacks on Partnership several signatures still The the
25 ago. are based done existing FEMA maps on studies The to up years
Are a builder? you
and are diversions domestic for irrigation small There use.
and Chehalis dry has mild, rainy subbasin summers. The Upper warm, winters,
continue find money parcel. purchase the this to to to try We
an County. citizens flooding for gain in information is issues on opportunity provide purpose The the to to
baleen came Did discovered ever from here in know oldest River right rocks Satsop that the the watershed? whale you
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The Partnership still lacks several signatures on the Intergovernmental Agreement.
The existing FEMA maps are based on studies done up to 25 years ago.
Are you a builder?
There are small diversions for irrigation and domestic use.
The Upper Chehalis subbasin has mild, rainy winters, and warm, dry summers.
It is extremely important to give people opportunities for nature
The purpose is to provide an opportunity for citizens to gain information on flooding issues in the County.
Did you know that the oldest baleen whale ever discovered came from rocks right here in the Satsop River watershed?
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Send comments or questions to the: Chehalis River Council