Stream Tender Magazine

June 2015 Issue

Bank Stabilization is a Primary Goal in the Bow Valley Riparian Recovery Program !

    The previous plantings on all three streams are showing positive results in bank stabilization and future erosion prevention. This will greatly reduce the amount of silt loading into the streams.

    Some erosion sites are recovering more quickly than other sites, but the long term benefits will show over time.

    This spring, the amount of frost heaving was exceptionally high, when compared with other spring thaws. Fortunately, many of the banks that have already been planted were held together by the root systems that are now establishing a hold in the softer soils along the stream banks.

    It is expected that after a few years of growth, the newly planted willows will be advanced in growth enough to withstand a major high flow event in the creeks.

    After two or three years, the root systems are strong enough and spread out far enough to re-enforce the unstable slopes of banks.

    This year, more plants will be added to previous stabilization sites, to make the remediation work more stable and insure adequate growth in the future.

    The outside stream bank on bends and oxbows of the channel are the most common stabilization sites that need our attention.

“ Every Spring Frost Heaving is a Major Cause of Unstable Stream Banks and Silt Loading into the Channel ”

Plantings at the Base of an Eroding Slope - Prevent Tow Erosion

    If there is no healthy riparian growth, such as willows and trees, on the outside bend of the stream channel, erosion can result. Over time, the base of an outside stream bank will experience “toe” erosion and cause the slope to destabilize.

    This can be extreme when the outside bend is elevated from the surface of the stream. The result of toe erosion on  high banks is

especially bad for silt loading into the streambed.

    Every year, during spring run-off or during a period of high precipitation, large amounts of soil will slide down into the stream, causing major silt loading over gravel substrate and accumulations in slow velocity areas of the stream channel.

    By planting willows and trees at the base of these eroding slopes

The banks will eventually stabilize and further silt loading will be brought to an end. Multiple plantings or treatments are required to  accomplish this goal.

    Over the past few years, Bow Valley Habitat Development has been working on this approach to stream bank stabilization. The results thus far are very encouraging and the program is ongoing. Look for future updates on this program.

An Elevated Outside Stream Bank with Major Toe Erosion at the Base

Willows and Trees are Planted at the Base of the Eroding Slope

Soil Enters the Stream

Channel Causing Silt

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Bow Valley Riparian Recovery Program 2015 is Even Larger

Than the 2014 Program !

    In December of 2014, in the issue of Stream Tender Magazine, I mentioned a goal of 14,000 plants for this year’s program. It was a lofty goal to set, but I was optimistic that we had a good chance of reaching it.

    I am please to report that we may well achieve the objective for the 2015 BVRR Program. So far, we have funding and commitments to plant over 13,000 plants, so there is a strong possibility

that we may get to over 14,000 yet this year.

    There have been some big donations from some of the corporations and NGO’s that are involved in this years work program. Recently, I found out that DFO was once again making a major contribution for funds, so all together the program for 2015 is huge.

    Last year, we planted a total of 10,500 plants over 11.5 kilometres of stream bank on all three streams and a few

small tributaries. The tributaries are Ranch House Spring Creek and Millennium Creek. The 2015 program will complete more plantings on the same streams and the area of stream bank will increase substantially.

    So far, this two year program will make a big difference on a large portion of the streams riparian habitat and I look forward to visiting the planted sites in the future, so that I can take some photos to share with you.