Six Steps to Restoration

by T.C. Dewberry
(adapted from Restoring the River: A Plan for the Chinook Watershed)

(From top to bottom) Male coho, female coho, male chinook, female chinook.
Drawings by Lisa Miles.

This restoration plan outlines a strategy for the restoration of Pacific salmon runs in the Chinook watershed. The plan is designed to halt both the decline of salmon populations and the decline in the health of the basin while rejecting the mistaken assumption that current knowledge offers the last word on the basin's restoration.

The condition of the basin reflects over a century of cumulative human impacts. However, it has recently begun to recover, and there is significant potential to restore many of its important attributes. Given the watershed's strategic location at the mouth of the Columbia and its high restoration potential, restoration efforts in the Chinook have broad regional significance.

The most significant human impacts in the lower watershed include a highway bridge and associated tidegate that restrict the flow at the river's mouth, extensive dredging and diking, removal of the riparian forest, road building, and clearcutting of the steep slopes.

Establish Refuges

Refuge areas must be established in the basin to protect critical areas from landslides and debris torrents, and to re-establish a more natural regime of sediment and organic matter dynamics within the watershed. Such areas are needed to restore natural stream processes to provide the highest quality salmon habitat. Refuges anchor other restoration efforts and minimize the risks of large landslides or debris torrents, which can overwhelm the capacity of the stream system to move material naturally.

Activities that would elevate the risk of landslides and debris torrents should be eliminated from the basin. Areas prone to such risks total approximately 630 acres, less than 8 percent of the watershed. Timber harvest should be prohibited in areas designated as refuges until significant capacity to process the sediment associated with landslides has been restored. A program of conservation easements or other economic incentives should be created to offer landowners an alternative to timber harvest.

Repair and Stabilize Roads

The road network in proposed refuge areas should be carefully examined and storm-proofed to withstand 100-year storm events. Any nonessential roads should be put to bed (i.e. dismantled and revegetated) to reduce the risk of mass erosion from steep hill slopes. Decommissioning unnecessary roads in refuges would also save substantial maintenance costs.

Protect and Restore the Valley Floor

Historically, large old conifers (primarily Sitka spruce, western hemlock, and western redcedar) dominated the valley floor of the Chinook basin. This is in contrast to the uplands, where patches of mature conifers existed within a mosaic of younger age classes.

In 1805, Meriwether Lewis and William Clark reported numerous conifer trees larger than 3 feet in diameter growing on downed logs at the mouth of the Chinook River. Big trees were cut from the streamside zone-and big logs cleared from the stream channel-in the early decades of settlement.

The watershed will not produce quality salmon habitat until substantial areas of the valley floor again support a mature conifer-dominated forest. The critical functions performed by intact forest on the valley floor include: shading streams to keep them cool, preventing debris floods, minimizing bank scour, providing organic matter to the stream ecosystem, and providing large wood that can create log jams in the channel.

Planting trees on streamside banks can speed the recovery of the riparian zones. Sitka spruce and western redcedar should be the dominant species planted; however, some big-leaf maple and willow should be planted on stream banks as well. Willow should predominate on the flats and in the lower river.

Cedars that can grow to maturity in the riparian zone are critical for long-term recovery in the basin.

Restore the Lower River Estuary

The Chinook River estuary is altered significantly from its historical condition. Lewis and Clark reported that the Chinook River was 300 yards wide at high tide. In the 1870s, the mouth was altered considerably, extensive diking moved the mouth by a mile. Today, the Highway 101 bridge and associated tidegate significantly alter tidal flow in the lower Chinook River.

The actions on the following pages will help restore the natural functions of the river's lower estuary:

Manage the tidegate to minimize its effect on tidal exchange. The tidegate currently limits the tidal flow within the estuary With management, the tidegate could accomplish its purpose of flood protection in the lower Chinook, while allowing for significant tidal flow. There is currently no evidence to suggest that saltwater intrusion would be a significant problem.
Develop a long-term plan for the removal or redesign of the tidegate and associated Highway 101 bridge. Even in the absence of the tidegate, it appears that the current Highway 101 bridge constricts the flow, limiting tidal exchange. Eventually the bridge will have to be renovated or replaced; any plan for re-engineering it should take the needs of the watershed and the people who live in it into account.
If controlling the tidegate results in flooding, consider diking the affected areas. This action represents a new perspective on the role of dikes. Historically, diking was performed to transform marshlands into agricultural lands. This plan proposes to dike agricultural and other developed lands, if necessary, to promote the restoration of marshlands.
Limit development in the lowland areas associated with the Chinook. Currently, the valley floor is sparsely developed and mostly agricultural. Limiting development will prevent problems such as nutrient loading from septic tanks and lawn fertilizer.
Construct accumulations of wood in limited areas within the Chinook estuary and Baker Bay. Historically, large accumulations of wood were found throughout Baker Bay and the lower Chinook. Today, few such accumulations exist. Many species, including juvenile salmon and other species such as herring, depend on these accumulations for spawning and/or rearing.
Encourage beaver dam development in the lower river. The activities of beavers will rapidly reconnect the stream channel with the valley floor, restoring considerable freshwater habitat. This single action may have the greatest short-term effect on juvenile fish production in the basin. Beaver dams may delay the return of adult chinook to the hatchery until the dams are breached by the first significant storm, but the benefits of enhanced production of young salmon far outweigh the costs of slightly impeded upstream migration.
Cooperate with Washington State University to design a project that integrates agriculture in the lowlands with recovery of natural marshlands. WSU owns a considerable portion of the lowland marsh, an area currently in hybrid cottonwood plantations. A pilot project aimed at developing profitable alternative agricultural products would enable other areas to be managed as marshlands.

Use the Hatchery to Support Restoration

The goal of the hatchery must shift from an emphasis on production to an emphasis on restoration of a diverse suite of life-history strategies. Hatchery fish need to be carefully selected to complement, rather than undermine, the specific restoration goals set for naturally spawning fish in the basin.

The following recommendations are proposed for the hatchery:

Use historical sources and information on current life-histories to document historical life history-habitat relationships in the basin.
Mark each fish in the hatchery according to its life-history strategy.
Base the number of individuals of propagated in the hatchery on the needs of the Chinook watershed and in the context of conditions in the lower Columbia River and the ocean.
Focus on improving fish survival rather than simply increasing the number produced by the hatchery.
Use hatchery facilities and a portion of the budget to pursue basic scientific investigations to improve our understanding of the ecology of the Chinook River system.

Evaluate the Results

On the Uplands:

Create GIS maps of forest vegetation ages and types in the basin.
Measure the miles of roads in the basin.
Record the number and location of debris torrents created during major storms.

On the Valley Floors:

Create GIS maps of vegetation classes.
Study the status of riparian planting areas.

In the Stream Channel:

Snorkel count for abundance and distribution in the basin each June.
Operate smolt trap at the hatchery.
Count adults and take scale samples to determine life-histories.
Evaluate the survival of the life-histories that occur and spawn naturally in the basin.
Count gradient-controlling jams including beaver ponds.

In the Estuary:

Complete a bathymetric map of the estuary.
Measure or estimate planar areas during high and low tides.
Measure physical tide flows (before and after managing tidegate).
Document vegetation types in the marshlands.
Estimate primary and zooplankton production (emphasize spring and summer months).
Evaluate fish utilization, food habitats, and growth.
Establish smolt trap at upper tidegate.

At the Hatchery:

Determine life-history strategies now present in hatchery stocks.
Evaluate the success of each life-history at each stage.
Determine the impact of artificially propagated life histories on the naturally spawning fish.
Evaluate hatchery practices such as feeding live food and conditioning to predators to determine effects on fish survival.
Investigate the interactions of hatchery management with conditions in the Columbia River and Pacific Ocean and the effects of harvest on the life-histories present in the Chinook

Thomas C. Dewberry works as a restoration ecologist for Ecotrust to analyze, oversee, and implement various landscape and habitat restoration projects. Restoring the River: A Plan for the Chinook Watershed was published by Sea Resources and Ecotrust in September 1997 and is now out of print.