Tag Archives | streams

Weir Removal…a dam good idea!

Weirs are barriers built in a stream to pool water for irrigation, recreation, and sometimes to generate power. They are found in many of our local streams, even though most are no longer in use, and often cause problems for juvenile fish. During times of low streamflow, these structures tend to be too tall for young fish to jump, and during high streamflow, the narrow opening in the weir causes the water to flow too quickly for young fish to navigate.

History of One Weir

Milk Creek WatershedwebMany years ago, crews at Camp Adams installed a weir on Nate Creek in the Milk Creek Watershed, to create a swimming hole for the retreat. Unfortunately, within a year the sediment buildup caused the swimming hole to become useless. This year, the current owners of Camp Adams felt it was time to return the stream to its original state, so they contacted the Clackamas Soil and Water Conservation District for assistance. Jenne Reische, riparian specialist, visited site visit and explained that once a stream is backed-up, gravel and debris that normally travels through the stream system becomes trapped. This causes the sediment build-up behind the weir and starves the lower part of the stream of needed woody debris and spawning gravel. Removing a weir and allowing a stream to flow naturally not only improves fish habitat downstream, but also opens up good habitat upstream.

Fixing the Problem

After many months of planning and permitting, the fall in-stream work window arrived and crews from Oregon Department of Fish and Wildlife brought in heavy equipment to remove the concrete and wood structure in Nate Creek. Prior to the weir removal, biologists routed the stream through a pipe to keep the deconstruction process from sending sediment and debris from the deconstruction downstream. As the water left the construction area, biologists quickly captured any stranded fish and released them downstream.
Removing the weir made Nate Creek a free-flowing stream. Additional improvements include two log jams and boulder clusters to provide places for insects to reside and young fish to rest. Crews planted native trees, shrubs, and small plants on the streamside to provide bank protection, shade, and habitat for the native birds and wildlife.

Success in the Stream

The Clackamas Soil and Water Conservation District and Camp Adams staff happily report that there is one less weir in the Milk Creek Watershed! “The Camp Adams community is excited and honored to be a part of local community efforts to restore and preserve the health and vitality of the Milk Creek watershed,” explained Natalie and Bob Becker, camp managers. “It is central to the mission of Camp Adams to use the natural resources of the property in ways that raise awareness of the dire need for conversations about our environment.”
“This is not a do-it-yourself type of project,” adds Reische, project manager for the District. “There are permits, in-stream timelines, and many considerations for protecting the water quality in the stream. We recommend interested landowners contact the Conservation District to help them navigate this process.”
For more information on weir removal on your property, contact Clackamas Soil and Water Conservation District at 503-210-6000.

A Rare Chance to Learn About Streams

November 18, 2012 - Light rain

One example of stream bank restoration photo by Tom Salzer

Is the area next to your river (known as the riparian area) eroding and falling off into the water each winter? Clackamas County Soil and Water Conservation District is happy to host a rare opportunity for landowners interested in learning from leading experts in the field of stream bank restoration. Come and learn why stream banks sometimes erode and what you as a landowner can do about it!

Streambank Erosion – a landowner workshop
September 20, 2014
8:00 a.m. to 11:30 a.m.
End of the Oregon Trail Museum
1726 Washington St. Oregon City OR 97045

Seating is limited, RSVP by calling Cathy at 503-210-6000 or e-mail to reserve your seat!

Speakers at this workshop are noted professionals in the field of stream bank restoration, and include:.

Janine Castro (USFWS, NMFS, PSU) – Janine, a fluvial geomorphologist*, is a regional expert in geomorphology with the US Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) in Portland, Oregon. She is an experienced instructor who provides local and national training on geomorphology and stream restoration. Prior to joining the USFWS, she worked for 10 years with the Natural Resources Conservation Service throughout the western United States.

Colin Thorne (Nottingham University, Portland State University) – Colin is a fluvial geomorphologist with an educational background in environmental sciences, civil engineering and physical geography. He has published 9 books and over 120 journal papers and book chapters. He has particular expertise in erosion, sediment transport and sedimentation.

*Fluvial geomorphology is a science devoted to understanding rivers, both in their natural setting as well as how they respond to human-induced changes in a watershed. – Bucknell University Environmental Center

Is Your Stream Bank Heading Downstream?

Milk Creek: Eroding streambank

Milk Creek: Eroding streambank

Stream bank erosion is a natural process and, in an undisturbed stream, it usually happens slowly over time. However, once a stream is disturbed and plants along stream banks are removed, this process speeds up at alarming rates.

Active stream bank erosion can lead to property loss, poor water quality, and loss of healthy conditions for fish. We have all seen erosion caused property loss with large chunks of bank slumping and toppling into the stream following each large rain storm.

How do I fix it?

One way to help repair these serious erosion problems is to plant trees, shrubs, and grasses in the area along the stream known as a riparian area. Healthy plants covering the stream banks and the area next to the stream will serve to protect water quality, provides habitat for fish and wildlife, and stabilizes stream banks.

Now is the time to start planning your stream bank repair project. When deciding what plants to use, it is a good idea to think about using native plants. Native plants are adapted to our local soils and moisture conditions, and provide food and habitat for our native wildlife. Some of the best shrubs for the riparian area are native willows like Pacific and Scouler’s willow or Red Osier Dogwood, which can be recognized by its bright red stems and small white flowers. Native trees to consider are Oregon Ash and Red Alder. Willows and dogwood form dense hedges with fibrous roots, which can greatly reduce water speed, in turn slowing down erosion. Oregon Ash also has a very strong root system that is excellent at holding soil in place.

The best time to plant trees and shrubs are when they are not actively growing, typically between November and March. If you live in an area with beaver, mice, or other wildlife, it may be necessary to protect your plantings with tree protection tubes. Keeping the ground around each planting free from competing grass and other plants will also help reduce wildlife damage.

While adding native plants typically reduces stream bank erosion, in more extreme erosion cases, such as when banks are steep, planting trees and shrubs may not be enough to stabilize the stream bank. When this occurs, other techniques may be necessary to control the erosion.

Where will I find help?

Your local conservation district can provide on-site technical advice to assist you with protecting and restoring your riparian area. For more information on stream bank restoration in Clackamas County, contact Clackamas SWCD Riparian Specialist, Jenne Reische, at 503-210-6011.

Mark the calendar!

Don’t miss out on this very special event hosted by the Clackamas County Soil and Water Conservation District.
Stream Bank Erosion – a landowner workshop
September 20, 2014
8:00 a.m. to 11:30 a.m.
End of the Oregon Trail Museum
1726 Washington St. Oregon City OR 97045

Seating is limited, RSVP by calling Cathy at 503-210-6000 or e-mail Cathy

Community, Conservation, and Hot Cider

Neighbors along Corral Creek were treated to a fun morning of greeting old friends and meeting new ones, while learning about the dam removal on their creek and the 2.5 miles of fish habitat that has been opened up to the resident cutthroat trout.

Last Saturday, 56 residents along Corral Creek gathered at the Magness Memorial Tree Farm, part of the World Forestry Center. While the kids were busy making fish prints and drinking hot apple cider, the adults found out about habitat improvements to the stream, managing pastures, maintaining septic systems, and additional conservation practices.

Community events like this keep landowners informed and quite often encourages them to request technical assistance for issues on their own property.

What natural resources can we help you protect?

Give us a call!

Clackamas County Soil and Water Conservation District


Obstruction Removed — Fish Jumping for Joy!

This in-stream dam on Corral Creek restricted passage for native fish.

This in-stream dam on Corral Creek restricted passage for native fish.

Exciting things have been happening in Corral Creek. Last month an in-stream dam was removed from the creek and constructed log jams were installed. The project restored natural stream processes and re-established 2.5 miles of stream habitat for native fish including cutthroat trout that live year-round in Corral Creek.

After consulting with stream engineers and obtaining necessary permits, the dam was taken apart, carefully removed, and hauled to a concrete recycler. Fish passage and natural stream flow was restored. The constructed log jams will help retain sediment and gravel where it would naturally occur. The trees and boulders that make up the log jam give juvenile fish a place to rest and hide when water is high and fast. Planting native trees, shrubs and grasses helped speed the recovery of the stream banks after construction.

 Corral Creek completed project

Project completed! Habitat is restored and Corral Creek runs freely.

To celebrate this project, a Corral Creek Neighborhood Social will be held at the Magness Memorial Tree Farm on November 9, 2013 from 9:00 a.m. to noon. There will be experts on stream and fish habitat, septic system maintenance, and woodlot management, as well as fun activities for kids.

The successful completion of this project is the result of a collaborative partnership between the Thomsons, Clackamas County Soil and Water Conservation District, Oregon Department of Fish and Wildlife, USDA Natural Resources Conservation Service, and American Rivers- NOAA Community Based Restoration Program.

What Are the Bugs Telling Us?

Got bugs?

Macroinvertebrate sampling to assess stream health

Macroinvertebrate sampling to assess stream health

If you live in the Clackamas River watershed, you may have noticed folks in orange vests looking under rocks and kicking the sediment in Doane and North Fork Deep creeks in early October. The Clackamas County Soil and Water Conservation District hired them to collect data on macroinvertebrates.

Macroinvertebrates are organisms without a backbone that are large enough to be seen with the unaided eye. They live in a waterbody or stream for an extended period of time, are sensitive to habitat loss, chemical pollution, and excessive sediment in the water. This makes them good indicators of overall stream health.

The streams in this story may not be the ones in your neighborhood, but macroinvertebrates live in all waterbodies. Do you know what is going on in your area creeks?

What kind of bugs are in the stream?

Macroinvertebrates can be divided into three groups. The first group is sensitive to warm water temperatures and acidity. This group needs high levels of oxygen in the water. This group includes mayfly, caddisfly, and stoneflies.

The second group is more tolerant of pollutants in the water. They include dragonfly, damselfly and scuds.

The third group is tolerant of polluted water that is warm, may have too much sediment in the water, too high or low acidity, and not enough oxygen. This group includes aquatic worms and midge larvae.

What did we find?

With the exception of our reference site on Tickle Creek near Sandy, the stream sites sampled in this “watershed check-up” support macroinvertebrate species able to tolerate degraded conditions. Very few sensitive macroinvertebrates (mayfly, caddisfly, and stoneflies) were found. We did find species able to tolerate elevated sediment loads and increased water temperatures.

The index used to score the macroinvertebrate community conditions show all sites were severely disturbed, except Tickle Creek that was rated slightly disturbed. Our consultant concluded that elevated water temperature and sediment load were problems at all sites.

What can you do?

Macroinvertebrate communities recover fairly quickly when their habitat conditions improve. This is one reason they are a good indicator of stream health. If sediment loads and warm stream temperatures are harming bugs in the stream, keeping soil out of the stream and shading the stream are things that will improve stream health.

The most economical and easiest restoration actions you can take are planting trees, shrubs, and grasses in the streamside area. Native vegetation provides many benefits including sediment and pollutant filtration, shading, insect food sources, bank stability, and eventually large wood for the stream. Other beneficial actions include erosion control practices on fields and barnyards.

Read the technical report

Linked below is the report, downloadable as a PDF file.

2012 Stream Benthic Macroinvertebrate Assessment
2012 Stream Benthic Macroinvertebrate Assessment
2.2 MB

We’re available to help

We can help you control erosion on your property and create a beautiful shaded streamside. Our assistance is free and we often have financial programs to help.

Call the Conservation District at (503) 210-6000 to find out more. In the Clackamas River watershed, you can also contact the Clackamas River Basin Council at (503) 303-4372 for riparian planting assistance.