Wednesday, August 17, 2016

Former Sundberg Property About 900 feet from Suspected Olympia Fault Line


Olympia’s Critical Areas Ordinance Updated, Gaps Remain

Above: Looking like Eastern Washington, the former Sundberg sand and gravel mine in Olympia as viewed on Wednesday from a surveyed county road and right of way called North Road, looking toward Grove Street and 20th Avenue. Cooper Point Road is to the west.Sitting on a critical aquifer recharge area, the property has been dramatically and illegally altered for decades, and features mounds of disturbed soil about 30 to 40 feet high.

Repeated requests to the property owner and his representatives by Little Hollywood to tour the property by the city's first public comment deadline of Friday, August 19 have not been acknowledged. 

By Janine Gates

The Olympia city council passed a critical areas ordinance on Tuesday evening that improves the last one, updated in 2004 and 2005, but it still has a long way to go.

As identified in a March 2016 memo to the city by its consultants, ESA Associates, of Seattle, says Olympia’s critical area ordinance still contains gaps.

The critical areas ordinance is required by the Growth Management Act (GMA), and the version passed mostly clarifies terms, streamlines code, and ensures consistency with the city’s recently adopted Comprehensive Plan.

Critical areas are considered to be wetlands, critical aquifer recharge areas, fish and wildlife habitat conservation areas, frequently flooded areas, and geologically hazardous areas.

The areas covered by the update are drinking water wellhead protection areas, habitats and species, streams and riparian areas, wetlands and small lakes, and landslide hazard areas.

A nine member working group met on July 26 to start identifying locally important species and habitats. Some species and habitats are known and others may be identified and considered through public workshops and meetings.

The first public workshop is scheduled for September.

“We expected to have this one meeting with this group but ran out of time so will be having a follow-up meeting, tentatively scheduled for Aug 29. 

After that meeting, our consultant will synthesize the technical information, comments and best practices into general recommendations for protection options, which will be the basis of the presentation to the public in September,” said Linda Bentley, senior planner for the City of Olympia, in an email on Wednesday to Little Hollywood.

The group’s membership and meeting minutes for the July 26 meeting have not yet been posted to the city’s critical area ordinance webpage but were obtained by request from staff.

The group’s two environmental organization representatives are Sam Merrill of the Black Hills Audubon Society and Daniel Einstein of Olympia Coalition for Ecosystems Preservation. 

The group also includes Theresa Nation of the state Department of Fish and Wildlife, a representative from Thurston County, three from the City of Olympia, and two of the city’s consultants.

Final recommendations for revising the code are scheduled to go to the city council in November.

Gaps Identified

Gaps in the city’s critical area ordinance include the fact that the city relies on the National Wetland Inventory and does not maintain any local mapping of delineated or potential wetlands. Several wetland model codes, categories, and buffer effectiveness guidelines were found to be outdated, and there was a general lack of alternative mitigation measures for wetland impacts.

In general, ESA Associates says that although the city has complete and reliable data for some critical areas, mapping for other areas are missing or incomplete.

For example, the city uses soils data to map steep slopes, but has not mapped any seismic hazards, severe erosion hazard areas, landslide hazards, or subsidence hazards, if present.

Green Cove Basin Concerns

Clearing up those gaps and areas of concern area can’t come soon enough for some residents of the Green Cove Basin area in west Olympia, as developers seem to know the city’s vulnerabilities. 

Multiple proposed land use applications for developments in the Basin are in progress. 

The Green Cove Basin is in the Eld Inlet watershed and contains steep slopes, ravines and canyons. Roughly bounded by Cooper Point Road on the east, Mud Bay Road on the south, Overhulse Road on the west, and Sunset Beach Drive on the north, it is protected by a 1998 Thurston County Comprehensive Plan. 

The area has been mapped as a critical aquifer recharge area by the county, but the city has not actually yet defined a critical aquifer recharge area, and instead relies on an identified wellhead protection area to serve the same purpose.

“Areas of ‘extreme’ aquifer susceptibility are mapped by the county as occurring near the city limits indicating similar unmapped areas of aquifer susceptibility may be present in the city,” says the ESA Associates report.

Property developer Jerry Mahan recently submitted a land use application to the city to convert the former Sundberg sand and gravel mine into a 177 single family housing development called Green Cove Park on the City of Olympia’s westside.

The exact area of this proposed development is labelled by Thurston County as an “extreme” aquifer recharge area.

Above: Tim Walsh, chief hazards geologist for the state Department of Natural Resources, gave an informative presentation about the history of earthquakes in the South Sound area at the annual meeting of the Olympia Historical Society and Bigelow House Museum in January. A maximum capacity crowd heard the presentation and many expressed that they were unaware that a fault runs under Olympia.

Olympia Fault Line Near Sundberg Property

The city has not mapped the city’s seismic hazards, and, as it turns out, the whole 104 acre former Sundberg sand and gravel mine property appears on county and state maps as being very near an earthquake fault line that runs through Thurston County.

So near, it’s about 900 feet from the property, and within about a half mile of the top of the hill on 20th Avenue near the proposed Parkside development on Cooper Point Road.

Tim Walsh, chief hazards geologist for the state Department of Natural Resources gave a presentation about the fault at the annual meeting of the Olympia Historical Society and Bigelow House Museum in the Coach House of the State Capitol Museum in January.

“We call it the Olympia structure but some people call it the Olympia fault,” said Walsh.

Walsh said it was initially identified on the basis of geophysical information. There is also paleoseismic data in support of an Olympia fault.

About 50 miles long, it was first mapped in 1965. In 1985, it was mapped from Shelton, near the Olympic foothills, southeast to Olympia, under the State Legislative Building, directly under the town of Rainier, to a point due east of the Doty fault, and apparently marking the northeastern limit of a band of southeast-striking faults in the Centralia– Chehalis area.

In 1998 a geologist saw enough similarity with the Seattle fault to speculate that it is a thrust fault.

Geologists Jack Odum and Bill Stephenson have also done seismic profiling along Steamboat Island Road and have made some interpretations of the Olympia structure to conclude that it is quite likely a fault.

Above: A close up of a slide by Tim Walsh, chief hazards geologist for the state Department of Natural Resources, showing the trajectory of the Olympia fault crossing  the area of Cooper Point and Eld Inlet very near the former Sundberg sand and gravel mine property. Click on image to enlarge.

Editor's Note, August 23: Please read note of clarification by Tim Walsh in the comment section under this article. 

Full Disclosure: Janine Gates is on the board of the Olympia Historical Society and Bigelow House Museum and heard Tim Walsh's presentation, along with a capacity crowd.

To read past stories about this land use proposal and other related Green Cove Basin developments, Parkside, and BranBar, go to Little Hollywood, www.janineslittlehollywood.blogspot.com and use the search button to type in key words.

For updated information about the Green Cove Park development, go to the City of Olympia website at www.olympiawa.gov or contact Cari Hornbein, City of Olympia Senior Planner, phone: (360) 753-8048, email: chornbei@ci.olympia.wa.us. 

2 comments:

  1. Hi Janine,

    The reason I made the comment about Olympia structure or Olympia fault is that it is not known whether it is a fault at all, much less one that could be called an “earthquake fault”. Not all faults on a geologic map are active, i.e., capable of generating earthquakes. The Olympia structure is a matter of research but it is at least premature to call it an earthquake fault, and it may not be appropriate at all, hence the weasel words. At this point, it is best to be much more circumspect.

    Regards,
    Tim Walsh

    Timothy J. Walsh
    Assistant State Geologist
    L.E.G. 355
    Department of Natural Resources
    Division of Geology and Earth Resources
    "Washington Geological Survey"
    P.O. Box 47007
    Olympia WA 98504-7007
    (360)902-1432; (360)791-3130 (cell)

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    Replies
    1. Tim, I respect your work and opinions, having attended graduate school with a former colleague, Joe Dragovich who also did excellent work! It has been thought that Butler Cove, with its steep north facing shoreline might be such a fault, producing that type of shoreline landform more recently than the last glaciation. Another clue, exists just uphill from the cove at the bottom (the creek crossing) of French Road. If you look upstream, up the two steep canyons drained by that stream there is an exposure of basalt bedrock rarely found in an area dominated by glacial deposits. It could be that fairly recent seismic activity exposed the basaltic bedrock at this locale. Other evidence of recent seismic activity can be found at Tumwater Falls which has had little time pass to wear down that surface since it was recently created. Chris Stearns

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