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U.S. DEPARTMENT OF THE INTERIOR

BUREAU OF LAND MANAGEMENT

Oregon / Washington

Greening Our Streams

Question: Why is the BLM putting lots back into streams?
Answer: To improve ecosystem health.

story by Scott Stoffel
photos by Rob Roninger


The waters of a Klamath River tributary can be seen moving slower than they have for 100 years thanks to 54 log structures inserted into a three-mile section of Spencer Creek northwest of Keno, Oregon, near the border with California.

This improvement in ecosystem function is a result of the BLM's efforts to reestablish the stream's original make-up of sinuosity, channel complexity, and gravel accumulations. By slowing down this stream, the creek's natural habitat may see subsequent increases to the population and distribution of aquatic species.

In 1995, the BLM created a partnership with the U.S. Forest Service (USFS) and the U.S. Fish and Wildlife Service (USFWS) to jointly develop the Spencer Creek Watershed Analysis and evaluate the stream's physical condition. Their investigation revealed the creek's capacity to support a healthy fishery which had degraded over time due to a reduction in naturally occurring logs in the stream.

The significant role large woody debris plays in stream ecosystem health has been misunderstood in the past. This was evident throughout the 20th Century when logs were actively removed from streams for utilization as lumber as well as to prevent flooding and erosion.

As a result, a significant number of trees had been removed in and around the creek's channel, leaving unnaturally low levels of logs within the streambed. And without these natural barriers to maintain a proper level of gravel in the stream, the water saw a decline in the quality of pools and cover that fish normally use for resting, holding, and rearing necessary to spawning their young.

Greening Our Streams
photo by Rob Roninger

Today, however, the multiple environmental benefits derived from leaving this material in watersheds are better understood. Large woody debris provides shelter for stream inhabitants, traps organic materials that serve as a food source for algae and invertebrates, and generates pools of deep water that provide a home for fish.

Equipped with this knowledge, the BLM prepared the Spencer Creek Restoration Treatments Assessment in 2004. The intent of this planning document was to improve a significant section - over six miles total - of Spencer Creek by: (1) increasing channel roughness to provide a diversity of aquatic habitats, (2) retaining and increasing spawning habitat, (3) creating low-velocity holding and rearing habitat for juvenile fish, and (4) enhancing pool complexity and cover. The addition of woody debris into this section of Spencer Creek was identified as the primary means for achieving these objectives.

The most recent phase of the Spencer Creek Helicopter Log Placement Project was implemented in October 2009. The services of Columbia Helicopters Incorporated, a leading expert on stream restoration in the Pacific Northwest, were contracted to place the 54 log structures. These structures were created from 220 logs salvaged from timber sales from the BLM and JWTR, a private timber company. The individual logs weighed up to 14,000 pounds each and ranged from 10 to 51 inches in diameter and 10 to 70 feet in length.

The total project cost is estimated at $145,000. The BLM provided a majority of funding and participated in all planning and contracting activities. The BLM's contracting officer's representative was on site to oversee project execution. Additionally, the USFWS participated in the same capacity as the BLM, and JWTR contributed towards contractor expenses and in-kind labor.

The outcome of this restoration project will continue to be examined over the next several years. Spencer Creek's aquatic habitat will be monitored to determine how it has been impacted by the log structures' presence. Surveys will be conducted to measure the project's effects upon native fish and amphibians, including Klamath River redband trout, Klamath small-scale suckers, lampreys, and Pacific giant salamanders. Knowledge gained from this effort will be used as the foundation for designing, implementing, and managing future stream restoration activities.


Learn more about the BLM's management of stream and other riparian ecosystem health online.