Floods

Major floods of 1996 and 1997 reminded us of the breath-taking power of nature.

After more than three decades of relatively small-scale storms and floods, a series of very large flood events hit the Pacific NW in the winters of 1996/7. These floods heavily damaged roads, trails, campgrounds, and other facilities on many National Forests. Many stream systems were damaged by landslides and debris torrents resulting from road fill/culvert failures. In response, the Pacific NW Region mounted an aggressive program of restoration. This program encouraged development of projects that reduced risk of future flood damage as well as repaired damage.

Project planning integrating facility repair with natural resource recovery needs was encouraged. Program areas receiving special attention were risks to health and safety, threats to high resource values and risks to capital improvements. Projects were carefully screened and prioritized by an interdisciplinary team; of approximately 2000 proposals submitted, half were funded and implemented. These projects repaired or replaced approximately 800 recreation sites, 700 miles of trails, 200 bridges and culverts designed to pass fish. Approximately 1000 miles of road were decommissioned or relocated; and almost 600 miles of landslide-damaged streams were treated (along with 7,500 acres of riparian area.)

Although floods can be very destructive to human-built facilities, flooding is a natural and very beneficial process for stream systems. The floods of 1996-97 reminded us of the many positive effects of large floods: scouring/deepening of pools for improved rearing habitat, cleaning/sorting of gravels used for spawning, introduction of large trees as structural material, creation of "off-channel" quiet water habitats, and distribution of fine sediment, nutrients and seeds on the floodplain for example. The native plants, fish and other organisms of the Pacific Northwest are adapted to the short term impacts and long term benefits provided by periodic flooding.

Greenwater River

The floods of 1996 extracted a heavy toll on the Greenwater River but also provided an opportunity for a brighter future. The Greenwater is a 75 square mile, Cascade watershed in NW Washington. It has extremely heavy recreation use and is important habitat to salmon and steelhead. The floods triggered several massive landslides along the main Greenwater road which went directly into the river. One of these removed 300 feet of road and delivered an estimated 23,000 cubic yards of sediment into the Greenwater channel.

To provide a long-term fix to this valley bottom road, a variety of treatments were explored and analyzed. A proposal which greatly improved road stability and which reconnected important fish habitat to the river was adopted. The repair work, which was implemented over a two year period, included relocation of three miles of the Greenwater road away from extremely unstable terrain next to the river, decommissioning of the old road and removal of a log stringer bridge, and the replacement of two culverts which were found to block fish passage. The result of these projects is a stable road and a river system that is better able to handle future flood flows.

The project was made possible through innovative leveraging of Federal, State and Private funding. Of the total $2.9 million project cost, 48 percent was Forest Service Emergency Supplemental Flood Repair Funds, 38 percent other federal funds, 10 percent private money, and 4 percent State funding. This complex project is an excellent example of interagency cooperation.

Asotin Watershed

Asotin Creek, a tributary to the Snake River, drains approximately 325 square miles of Asotin and Garfield counties in southeastern Washington State. Cooperative watershed programs, initiated by the Bonneville Power Administration (BPA) and the Natural Resource Conservation Service (NRCS), are now coordinated by the Asotin County Conservation District (ACD).

Three salmonid species are listed under the Endangered Species Act: Summer Steelhead, Spring Chinook Salmon, and Bull Trout. Resident Rainbow Trout also occupy streams in the Asotin watershed.

Flood Impacts and Management Response
In 1996, the waters of Asotin Creek peaked on February 9th after a week of warm Pacific storm surges brought rain on a snow cover over frozen ground. This pattern was repeated the following winter with even higher flows coming on the first day of the New Year, 1997. The results included severe soil erosion from upland areas, numerous slope failures and extensive damage to roads, recreation trails, stream channels and property.

Effects on aquatic habitat included reduced riparian vegetation and loss of pool habitat and wood debris complexity. Flooding increased sediment flows to the main stem of Asotin Creek. One of the key flood-related instream needs was restoration of pool to riffle ratios for adults and juveniles on the North Fork of the Asotin Creek.

The project was made possible through a combination of Federal funds. Of the total $82,000 project cost, 67 percent was Forest Service Emergency Supplemental Flood Repair funds, 32 percent was Federal Highway funds, and 1 percent was contributed by the Natural Resource Conservation Service.

Flood Projects
Three projects were completed in the Asotin Creek watershed: trails, roads and channel. The North Fork Asotin Creek Trail was stabilzed. The roads project consisted of repairing sections of an open system road and decommissioning 1.5 miles of riparian road in the Lick Creek drainage. Habitat features and channel control structures were placed to enhance channel stability and aquatic habitat in Asotin Creek.

Fish Creek

This project is an excellent example of flood repair on a watershed scale. Fish Creek, located in the Mt. Hood National Forest about 45 miles southeast of Portland, had some of the most severe flood damage seen anywhere in the Region. This 30,000 acre, "key" watershed was identified for priority restoration work even before the floods. Extensive roading and timber harvest, coupled with naturally unstable terrain, set the stage for the "100 year" floods of 1996. When the water receded, less than 10 percent of the 143 miles of road were readily accessible. Surveys found over 200 landslides which scoured 15 miles of valuable salmon habitat.

A critical question faced the Forest... "How do we repair the damage?"

Drawing upon a "blue ribbon" panel of scientists, years of valuable research and monitoring and a comprehensive analysis of the watershed were used to understand why damage in Fish Creek was so much worse than surrounding areas. The clear conclusion was that comprehensive, watershed-scale treatment was needed to ensure long-term recovery. Bold, innovative actions were called for.

The repair of Fish Creek established a decisive course for accelerated recovery to a healthy, stable watershed. The restoration and repair includes:

• Removing road risks and liabilities by decommissioning (70%) and/or stablization (30%) of the entire road system. Special emphasis was the obliteration of selected valley bottom roads in areas of critical fish habitat.
• Restoration/stabilization of major landslides and debris torrents.
• Restoration of stream channel and fish habitat at more than 10 key locations in the watershed.
• And, Monitoring to ensure the effectiveness of flood repair efforts

It is expected that Fish Creek flood repair will bring a variety of benefits - a more stable/resilient watershed, improved water quality and fish habitat, and an area offering a wide range of recreational opportunities. The project is a model of integrating science and management at an ecosystem scale.

Regional Process

Total damage from both series of floods was so widespread and severe that planning for recovery required special organization and operational procedures. An interdisciplinary strike team was formed and tased with the development of a Regional Damage Repair Strategy. This included:

• Development of criteria for project prioritization and selection
• Creation of project repair proposal forms
• Assembling a team to review and select projects, and
• Development of procedures for project oversight tracking and accomplishment reporting.

Nearly 3000 individual project proposals were received. These represented varying levels of damage on all 20 Forest/Administrative Units in the Region. Each project proposal was individually reviewed and prioritized by each member of the strike team. Individual ratings were discussed and a repair priority was established for each project. Project selection was documented in the database used to organize the projects. The submission, review and selection process required a tremendous amount of effort from personnel at all levels of the organization. Regional project review and prioritization alone required 3-4 person-months.

Throughout this process, special care was given to ensure the greatest benefit from available funding. Particular emphasis was given to project proposals that repaired damage and reduced or eliminated future risk of flood damage. Categories of work that received special attention included risks to human health and safety, threats to high resource values, and risks to capital improvements.

Development and application of the Damage Repair Strategy was critical to the success of the Flood Recovery Program. Although only 51% of the projects were selected, virtually all of the high priority and a significant number of medium priority projects were funded. Strategic implementation helped ensure that the repair program was effective in addressing critical risks to life, property and a wide range of resource values.

Accomplishments

"The land is better than we found it". This is something that hundreds of Flood Recovery Program people can say with pride. They have combined careful planning, commitment and hard work to make this programs' many accomplishments worthy of special recognition. The strong commitment to improve human safety, hasten the recovery of damaged resources and minimize liabilities from future floods is reflected in more than 1,450 projects completed on 20 National Forest/Administrative units. Due to the very large scale and extensive planning and design requirements of the program, full implementation required four years of sustained effort. On many Forests, flood repair became the primary program for accomplishing watershed restoration goals. Leveraging of specially appropriated Emergency Supplemental Flood Repair funds, with other resources program funds increased overall program accomplishments. Coordination and cooperation with a variety of State and Federal agencies increased overall program quality.

Special post-flood evaluations were used to analyze flood damage mechanisms at road crossings and in-stream habitat elements. These Region-wide efforts provided specific information for improved design and repair of flood damage. Both the road crossing and habitat evaluations have been published and are available for immediate use.

A review of total project accomplishments provides insight into the scope of the Flood Recovery Program. More than 3,500 miles of road were reconstructed or stabilized. Nearly 60 miles of road were relocated; nearly 900 miles of road were decommissioned; and more than 200 road/stream crossings were replaced to allow unimpeded fish passage and accommodate future large-scale floods. Nearly 600 miles of damaged streams were treated and over 7,500 acres of riparian and erodable upslope areas were re-vegetated. 695 miles of trail were repaired or relocated, and 810 recreation sites were repaired...often requiring redesign or relocation of sites and facilities.

Monitoring, on many Forests, will track near term success of this work. Lessons from the floods and the recovery program will better prepare the Region to respond to future events.