Riverbank Restoration Guide Internet

A Guide to Bank Restoration Options for
Large River Systems:
Part II Bioengineering Installation Manual

MWMO Watershed Bulletin: 2010-3
Prepared for the MWMO by:
Great River Greening

A Guide to Bank Restoration Options for Large River Systems:
Part II Bioengineering Installation Manual

Prepared for the Mississippi Watershed Management Organization by:

Contributing Authors:
Todd Rexine, Great River Greening Operations Manager
Dan Kalmon, Mississippi Watershed Management Organization Planner & Program Manager
Daniel Tix, (former) Great River Greening Conservation Director

Assistance from:
Sol Bijnagte, (former) Landscape Ecologist at Great River Greening
Tony Randazzo, (former) Landscape Ecologist at Great River Greening

Thank you to the staff from the following organizations: Minnesota DNR, USGS, Mn/DOT, US
COE, NRCS, U of M St Anthony Falls, and MNRRA who reviewed various stages of this project as
well as provided resources for: the modeling of the river; assembling the bio-engineering and
stabilization practices and developing the written guidance.

Published by:
The Mississippi Watershed Management Organization

Suggested Citation:
Mississippi Watershed Management Organization. 2010. A Guide to Bank Restoration Options for
Large River Systems: Part II Bioengineering Installation Manual MWMO Watershed Bulletin 2010-3.
95 pp.

Front Cover: Riverbank photos near downtown Minneapolis. Clockwise discription starting in the
upper left: eroded bank; 10 to 25% vegatated bank; Minneapolis Park and Recreation Board bank
restoration sites using bioengineering. Photograph by: Daniel Kalmon, Mississippi Watershed
Management Organization

1224 Marshall Street NE, Suite 201
Minneapolis, Minnesota 55413-0136

(612) 465-8780
(612) 465 8785 fax

www.mwmo.org

A Guide to Bank Restoration Options for Large River Systems:
Part I Riverbank Restoration Planning Software

Prepared for the Mississippi Watershed Management Organization by:
LimnoTech

Contributing Authors:
Todd Redder, LimnoTech
Hans Holmberg, LimnoTech
Dan Kalmon, Mississippi Watershed Management Organization Planner & Program Manager
Daniel Rucinski, LimnoTech

Assistance from:
Thank you to the staff from the following organizations: Minnesota DNR, USGS, Mn/DOT, US
COE, NRCS, U of M St Anthony Falls, and MNRRA who reviewed various stages of this project as
well as provided resources for: the modeling of the river; assembling the bio-engineering and
stabilization practices and developing the written guidance.

Published by:
The Mississippi Watershed Management Organization

Suggested Citation:
Mississippi Watershed Management Organization. 2010. A Guide to Bank Restoration Options for
Large River Systems: Part I Riverbank Restoration Planning Software MWMO Watershed Bulletin
2010-3. 95 pp.

Front Cover: Riverbank photos near downtown Minneapolis. Clockwise discription starting in the
upper left: eroded bank; 10 to 25% vegatated bank; Minneapolis Park and Recreation Board bank
restoration sites using bioengineering. Photograph by: Daniel Kalmon, Mississippi Watershed
Management Organization

Minneapolis, Minnesota 55413-0136

(612) 465-8780
(612) 465 8785 fax

www.mwmo.org

Minneapolis, Minnesota 55413

(651) 287 0948
(651) 287 1308 fax

www.mwmo.org

Abstract

The Mississippi Watershed Management Organization (MWMO) has developed a guidance
document and planning software for bank restoration on large river systems.

Physical characteristics of the riverbank, along with predicted shear stresses across a full range of
flows, are used to classify and recommend bio-engineering applications that restore and protect the
riverbanks of the Mississippi River.

This effort included: writing an installation manual, field surveys and data collection, modeling, and
data synthesis. Field surveys were conducted to collect information on bank profiles and slope,
vegetative cover, soil type, and existing structures or protection measures. Two-dimensional
hydrodynamic modeling of the Mississippi River from the Hwy 694 bridge to Ford Dam has been
conducted to assess shear stress and critical bank elevations. Planning software was also developed
to allow property owners to select locations, review physical data and modeling results, and choose
from applicable bio-engineering applications for their site.

The MWMO anticipates further development and application of this tool, in cooperation with local
and state authorities, as a planning resource other organizations can replicate and utilize for TMDLs
and Implementation Plans.

Minneapolis, Minnesota 55413

(651) 287 0948
(651) 287 1308 fax

www.mwmo.org

NOTICE: The Mississippi Watershed Management Organization, Great River Greening, and LimnoTech Inc are not liable
for damages or losses that may result from the installation of any of the recommended practices in this guidance manual. It is the
landowners’ responsibility to assure that the practices installed on their sites do not result in damages or losses to persons or
property. This guidance manual provides a range of restoration options for various sites based on a generalized classification of
the riverbanks within the MWMO. It is meant to provide landowners with a list of potential riverbank restoration practices.
Landowners must conduct any analysis needed to determine which of these practices, if any, are suitable for installation on their
sites given site specific characteristics.

A Guide to Bank Restoration Options for Large River Systems: Part II bioengineering installation manual

Table of Contents
Purpose of the Guide .................................................................................................................................................... 1
Introduction........................................................................................................................................................................ 1
Mississippi River Dynamics ........................................................................................................................................ 3
Assessing Riverbank Zones....................................................................................................................................... 5
How to Recognize Bank Stability Problems......................................................................................................... 7
What is Working Along the River.............................................................................................................................. 9
Steps to a Successful Project.................................................................................................................................. 10
Case Studies .................................................................................................................................................................. 17
Slope Restoration, St.Croix River, Lakeland, MN ...................................................................................... 17
Bank Restoration, Vermillion River, Hastings, MN..................................................................................... 18
Toe Restoration, St. Croix River, Lake St. Croix Beach, MN................................................................. 19
Technical Sheets: River Bank Restoration Solutions................................................................................ 21
Technical Sheet 1: Vegetated Erosion Control Blanket..................................................................... 23
Technical Sheet 2: Bio-logs .......................................................................................................................... 25
Technical Sheet 3: Live Stakes ................................................................................................................... 27
Technical Sheet 4: Live Fascines............................................................................................................... 29
Technical Sheet 5: Brush Mattress ............................................................................................................ 31
Technical Sheet 6: Tree Revetments........................................................................................................ 35
Technical Sheet 7: Vegetated Geogrids .................................................................................................. 39
Technical Sheet 8: Rootwads....................................................................................................................... 41
Technical Sheet 9: Crib walls ....................................................................................................................... 45
Technical Sheet 10: Riprap with Live Stakes......................................................................................... 47
Technical Sheet 11: Rock Barbs with Live Stakes .............................................................................. 49
Technical Sheet 12: Gabions with Live Stakes ..................................................................................... 53
Technical Sheet 13: Retaining Walls......................................................................................................... 55
Technical Sheet 14: Soft Armor Walls ...................................................................................................... 57
Appendix A: Plants for Live Cuttings .................................................................................................................... 59
Appendix B: Plants....................................................................................................................................................... 60
Appendix C: Practices Tables ................................................................................................................................. 61
Appendix D: Riverbank Assessment Sheet ....................................................................................................... 63
Appendix E: Soil Classification................................................................................................................................ 65
Appendix F: Vegetation Cover Percentage ...................................................................................................... 67
Appendix G: Understanding Our Streams & Rivers, MnDNR..................................................................... 69
Appendix H: Suppliers ................................................................................................................................................ 73
Appendix I: Minneapolis Regulations .................................................................................................................. 77
Bibliography .................................................................................................................................................................... 81


Glossary

The following list of terms, defines the intended meaning of terminology and phrases that are used in this
manual.

Bank Zone The area of the riverbank above the toe, located between the normal water
level and the bankfull elevation.

Bankfull This is the top of the channel. It occurs at the top of the bank and bottom of
the upland. For this stretch of the Mississippi it is demarked by a change in
the slope at the top of the bank; the presence of a floodplain area or at the
start of the 100 year flood elevation in reaches with vertical embankments that
continue beyond the 100 year flood elevation

Basal end The end of a live cutting where it was cut from the parent plant.

Low Water The lowest annual elevation of a stream or river.

Colluvial Slope A loose deposit of rock debris accumulated through the action of gravity or
rain-wash making up a slope.

Crib wall A soil bioengineering practice used to stabilize stream and river banks. The
crib is a hollow, box-like structure of interlocking logs or timbers. The
structure is filled with rock, soil and live cuttings or rooted plants.

Dead Stout Stake Lumber stakes used to secure soil bioengineering practices.

Erosion The wearing away of soil by water, wind, or ice.

Erosion Control Blanket A temporary protective blanket laid on top of bare soil that is vulnerable to
erosion; commonly made of mulch, wood fiber, straw, or synthetics.

Flora Plant life

Fauna Animal life

Gabion A wire basket or cage filled with rocks used to stabilize riverbanks or slopes.

Hydroseed Seed, mulch, and water are mixed into a slurry and then sprayed out of a hose
onto the ground. Commonly used on steeper slopes.

Invasive Exotic Species Species that are non-native (or alien) to the ecosystem and whose introduction
causes or is likely to cause economic or environmental harm or harm to
human health. (Executive Order 13112). Invasive species can be plants,
animals, and other organisms (e.g., microbes). Human actions are the primary
means of invasive species introductions.

Live Fascine A bioengineering technique used to stabilize riverbanks. A long bundle of live
cuttings bundled together with rope and placed in a shallow trench.


Ordinary High Water When describing a river this is the elevation at the top of the bank or channel.
Level (OHWL)

Reach A section of river that shares similar characteristics.

Riprap The use of larger stone to provide immediate and permanent riverbank
protection.

Restoration Practices used to stop or prevent erosion which include the installation of
vegetation at a density of 10% of minimum landcover or match existing
vegetative density, whichever is greater. Vegetation used is native to the local
ecosystem (see density photos in appendix G)

Stabilization Practices used to stop or prevent erosion which do not necessarily include the
installation of vegetation at a density of 10% or match existing vegetative
density, whichever is greater (see density photos in appendix G)

Rooting Hormone A hormone applied to the basal end of live cuttings to help stimulate root
growth.

Rootwad The use of locally available logs and root fans to add physical habitat to
streams and rivers in the form of coarse woody debris and deep scour
pockets.

Scour Downward vertical erosion in a channel bed.

Shear Stress The stress exerted on a stream or river bank that is the product of the energy
slope, hydraulic radius, and unit weight of water.

Sloughing On a river or stream this is when the bank collapses from either being
undercut, oversaturated, or over-steepened.

Sheet pile Flat panels of steel, concrete or other approved material. Typical applications
include toe walls, flanking and undermining protection, grade stabilization
structures, slope stabilization and earth retaining walls.

Soil bioengineering The use of live and dead plant materials in combination with natural and
synthetic support materials for slope restoration, erosion reduction, and
vegetative establishment.

Splash Zone The water surface is most commonly in this zone. It lies between low water
and normal high water. This zone is generally poorly vegetated, but emergent
vegetation may be present in slow-moving water.

Stretch A section of a river or stream.


Toe Zone The area of the riverbank between the normal water level and the upper edge
of the bottom of the channel.

Thalweg The deepest portion of the channel.

Upland Zone The portion of the bank located above the bankfull elevation.

Water Jetting A process where high-pressure water is used to create a hole in the ground to
plant cuttings.


Purpose of the Guide

This guide has two parts: the Bioengineering Installation Manual and the Riverbank Restoration Planning
Software. The guide will assist riparian landowners with restoration activities along the Mississippi River and
other similar large river systems. The information in the guide is tailored to specific river reaches within the
Mississippi Watershed Management Organization’s (MWMO) boundaries (figure 1). However, there is a
custom function within the planning software that allows landowners along other similar large river reaches
to identify potential bioengineering practices for their individual site. Furthermore, this guide was developed
for public use and replication. As such, the MWMO is willing to assist other large river managers in tailoring
the installation manual and planning software to the systems they manage.

Currently there is no guide for large river systems that assists landowners in ecological restoration of eroded
riverbanks. The planning software suggests bioengineering practices best suited for restoring the toe/splash,
bank and upland zones of the riverbank. These suggestions change as the riverbank’s reach characteristics of
slope, soils, depth to bedrock, shear stress, and vegetation density change. The manual provides landowners
with additional information on permitting requirements within the MWMO and step by step how to guidance
in assessing their own property for erosion and riverbank restoration solutions. Landowner’s that apply the
bioengineering practices recommended in this guide will restore the ecological and aesthetic benefits to the
Mississippi’s riverbanks while eliminating near-bank erosion problems.

Introduction
Riverbank restoration is a means of restoring, protecting and stabilizing the banks of rivers against scouring,
flooding and erosion. This installation manual, along with the restoration planning software, is a means for
riparian landowners to gain an understanding of possible bioengineering restoration practices that could be
implemented along their stretch of the river.

There are many means to accomplish bank restoration in eroded areas. Traditional riverbank stabilization,
methods used have focused on hard armoring practices such as riprap and block, void of any vegetation when
installed. The bioengineered practices laid out in this guide will help restore the natural landscape of the
Mississippi River Critical Area as it passes through an urbanized Minneapolis corridor. This is type of
restoration will resolve near bank erosion issues and improve aquatic and terrestrial habitat within a corridor
that has become so fragmented.

1

Figure 1: Mississippi Water Management Organization Boundary

2

Mississippi River Dynamics

As the Mississippi River winds its course through Minneapolis,
from Interstate 694 to the Ford Dam, there are a variety of
changes along the banks as well as the elevation of the river
itself. Not only does the river itself change through this stretch
but so does the surrounding landscape and land use. The
Mississippi River is also part of the larger Mississippi Flyway
which is a migration corridor for North American birds to
South America. The river is also a means for economic traffic West Bank Looking Downstream
from barges and tug boats to fishing and tourism. There is a Dan Kalmon
complex balance between human needs and the needs of the
flora and fauna that have adapted over centuries to the
conditions along the river.

As the river makes its course from the Interstate 694 bridge
south there are several distinct changes. The upper area still has
a natural feel as the river is bordered on both sides by city or
regional park systems. The banks of the river are still relatively
intact at this point as vegetation is holding the slopes. The
river channel itself is still relatively shallow and there are points
where stone riffles are apparent. Minor signs of erosion are
West Bank Looking Upstream
apparent but this is primarily from wave action and flooding. Dan Kalmon

By the 42nd Avenue bridge human presence on the river
begins to become more prominent. In this area is the city of
Minneapolis’ water treatment plant where water is treated for
the more than 372,000 residents (2006 census) and surrounding
communities. The riverbank at this point begins to become
more fragmented and less natural. There are still adjacent land
use areas of park but there is also the presence of industrial and
residential areas. This is also the upper limits of the Army
Corps shipping channel for barge traffic. In this area
vegetation on the riverbanks begins to break up. This is
especially true on the western riverbank where heavier West Bank Looking Upstream
industrial uses are located, and there is a need for docking Todd Rexine
barges. The industrial bank of the river is composed primarily
of vertical sheet pilings. Erosion from concentrated areas of
stormwater runoff, stormwater outfall discharge pipes,
flooding, and wave action is more apparent. As well as erosion
caused by human trampling of vegetation along the river in the
form of paths.

At Lowry Avenue bridge the riverbank opens up as the river
gets closer to downtown Minneapolis. The natural landscape
gets even more fragmented and fractured. Adjacent land use is
a mix of parks, commercial, residential, and industrial areas.
Looking Downstream into Downtown
Some of the park land tends to be more open allowing views Todd Rexine
and easy access to the river while the industrial area terminates
just upriver from the Broadway Avenue bridge.

3

Several changes exemplify the river in downtown Minneapolis.
Buildings, roads and sidewalks begin to encroach on the
riverbanks. The riverbank is primarily composed of vertical
walls or sheet pilings with the exception of Nicollet Island
which has steep soil and vegetated banks. This area also
includes St. Anthony Falls and the two upper Locks and Dams
on the Mississippi River. This area is witness to the only falls
on the river along with largest single drop in elevation.
Between the upper and lower lock there is a 73 foot elevation
change.

Downstream from St. Anthony Falls there are a couple isolated Looking Upstream at Downtown (West Bank)
floodplains as the Mississippi flows through a river gorge, Todd Rexine
ending the MWMO reach with one more significant elevation
drop by Ford Parkway at the Ford Dam (Lock and Dam 1).
The gorge area is typified by bluffs and steeper banks carved
out of the limestone. There tends to be more tree canopy on
the banks than in downtown, and buildings are set back further
from the bank. The land adjacent to the river in the gorge area
is mostly park land either maintained by Minneapolis or St.
Paul.

With all of these changes on this short stretch of the river there
is a dynamic relationship between the river and the landscape Downstream East Bank (Washington Ave)
surrounding it. Tributary streams and rivers have been put into Dan Kalmon
pipes and now flow directly into the Mississippi through
culverts. There are stormwater outlets that flow directly or
indirectly to the river from the surrounding city. This,
combined with other influences on the river, can produce a
delicate balance in preserving the resources of the Mississippi
River.

Upstream East Bank
Dan Kalmon

East Bank Floodplain
Dan Kalmon

4

Assessing Riverbank Zones

Bankfull

Normal water

Low water

Upland Bank Toe/splash

River Bank Cross Section,
LimnoTech Inc.

Four zones are usually used when describing riverbanks. According to the elevation relative to water level,
from bottom to top, these zones are: toe, splash, bank, and terrace (Allen and Leech 1997). In this guidance,
the terrace is more generally described as an upland zone and toe and splash zones are combined. A copy of
the assessment worksheets used to assess the MWMO’s portion of the Mississippi River is included in
appendix D.

Toe Zone
The toe zone is located between the upper edge of the bottom of the channel and normal normal water level.
This zone is generally underwater, but is exposed during droughts. Portions may be exposed in the winter of
each year. Except in slow moving portions of rivers, this zone is generally unvegetated. However, this zone
may include large portions of backwaters and flooded, slow-moving inlets and bays. Emergent, floating, or
submerged aquatic vegetation may be present in this zone.

Importance of vegetation in the toe zone:
The emergent vegetation in this zone contributes to bank stabilization primarily by diffusing wave energy
before it reaches the banks. In small channels it may also serve to diffuse current to a small degree, but
generally vegetation will not be present in the toe zone of large river channels. However, rooted plants should
be established wherever possible for securing sediment and providing wildlife habitat.

Splash Zone
The water surface is most commonly in this zone. It lies between low water and the normal water level. This
zone is generally poorly vegetated, but emergent vegetation may be present in slow-moving water. Areas of
the bank that are exposed for extended periods may support small annual plants and suckers from plants
higher on the bank.

Importance of vegetation in the splash zone:
Emergent vegetation in this zone can be critical for diffusing wave action against the bank and securing in-
stream sediments and thus, should be established whenever possible. However, most reaches will not support
vegetation in the splash zone. Small annual plants that begin growing from seed after river levels have

5

dropped below the normal water level form an interesting, ephemeral plant community; however they have
little function for bank stability though they do provide valuable seed sources for various wildlife species.
Therefore, areas where these are present should be protected from disturbance during installation of bank
restoration practices. Deep-rooted plants located high in the splash zone or in the bank zone can significantly
contribute to soil stabilization in this zone as well.

Bank Zone
The bank zone lies above the normal water level up to bankfull (a terrace or other change in slope). For
purposes of this study in areas where there is not a floodplain or terrace due to a vertical embankment, the
top of the bank zone is the same as the 100yr flood elevation. The bank zone may be subjected to heavy
flows during high water stages. Rooted vegetation generally occurs in the upper portion of the bank zone
under stable conditions.

Importance of vegetation in the bank zone:
Vegetation should be maintained in this portion of the riverbank, where it provides the greatest benefits for
stabilization, water quality, and habitat. The roots of the plants in the bank zone also contribute to
stabilization in the splash zone. The bank zone provides a buffer from upslope erosion and prevents the
upper slopes from sloughing into the channel. Dense vegetation in this zone slows water flow and reduces
wave energy during flood stages, further protecting upper slopes from erosion and wave action.

Upland Zone
The upland zone occurs above the level of bankfull. It may be a narrow crest of the natural levee between the
floodplain and the main channel or it may be a level floodplain terrace. For sites without a broad floodplain,
the upland zone is generally sloping upward away from the riverbank above bankfull. Portions of the upland
zone may become flooded during high water.

Importance of vegetation in the upland zone:
Vegetation here is critical and should be established and protected. Plants here stabilize the slopes and
minimize erosion from above. The vegetation here also serves important functions for the bank below by
providing dense roots behind the bank and reducing the likelihood of bank fracturing. In addition, vegetation
from the upland zone will spread into the bank zone when portions of the bank zone are disturbed. Other
benefits of vegetation here include the sheltering of the lower banks by overhanging trees, wildlife benefits of
riparian vegetation, and contributions of coarse woody debris to the river.

6

How to Recognize Bank Stability Problems
There are various influences that affect the degradation and stability of river banks. Some of the more
common problems that influence the degradation and stability of river banks are erosion, pollution, invasive
species, and low biological diversity. Anyone of these can cause problems for a site but often times these
problems influence each other, making early detection a key.

Erosion
Erosion is caused in areas where there has been some
form of disturbance. Typically along the Mississippi,
erosion occurs where external factors have removed
vegetation, exposing bare soil and then either river-way
flood waters or landside stormwater runoff can wash
away the soil. Early signs of possible areas of erosion
are: small channels cut into a slope, foot paths where
vegetation is bare, areas where water is running directly
over a slope. The earlier these erodible areas are
recognized and remedied, the less work needed to
restore the area. Eroding trail
Dan Kalmon
Pollution
The watershed of the Mississippi River is large and
covers a diverse landscape. Depending on its geography,
location on the river, and pollutant sources, a site may,
contribute a varied amount and a wide-range of
pollutants. Sources include: existing pollutants in the
river (as it enters the MWMO’s reach), multiple stream
inlets, stormwater outfalls, activities on the river, and
various adjacent land uses that drain into the river
system. Pollutants, depending on their form, disrupt
plant growth, cause fish kills, induce algae blooms, and
contaminate the soil.

Whether in an urban or rural setting, attention should
be paid to how water drains across the landscape.
Water running across surfaces tends to pick up
pollutants like grass clippings, soil particles, nutrients,
heavy metals, and hydrocarbons. The more water is
loaded up with soil particles, the greater its ability to
scour and erode riverbanks.
Spilt paint washing into a storm drain.
Anina Nielsen

7

Invasive Exotic Species
Invasive exotic species are a concern on any site when
trying to reestablish native vegetation. Typically invasive
exotic species were introduced to North America from
Europe or Asia for agricultural purposes, as ornamentals;
in essence, because they had a specific growth
characteristic that was found desirable. Often times, too,
they were introduced inadvertently or accidentally.
Eventually these plants found their way into the native
landscape where they have thrived. Many times a single
invasive species will move into a site and choke out
multiple native species resulting in a singular invasive
species stand. Typically, invasive tree and shrub species Buckthorn
such as buckthorn block out the sun leaving bare earth that
is easily eroded by runoff, wave action, or flooding. As a
result, where native flora is displaced there is an increase in
soil erosion.

Before beginning any restoration practices in a specific
area, invasive species should be identified, and controlled.
There are several ways of treating a site that has invasive
species present depending on how prevalent they are on
the site. If the infestation is minimal (less than 15%
cover), hand pulling or digging out may be an option. For
areas that have large infestations (50% cover or greater),
the site may need to be treated with an herbicide. Due to
the proximity to water an aquatic herbicide should be used.
The management of invasive species is an ongoing task as
the seeds can stay viable in the soil for several years. The
initial treatment of a site is the largest and most time Amur Maple
consuming. After the first year, maintenance is reduced to Todd Rexine
pulling or spot treating areas before they go to seed.

Some invasive species that have been observed on the river include: Common and Glossy
Buckthorn (Rhamnus cathartica and Rhamnus frangula), Exotic Honeysuckle (Lonicera tartarica,
Lonicera morrowii, and Lonicera x bella), Amur Maple (Acer ginnala), Reed Canary Grass
(Phalaris arundinacea), and Purple Loosestrife (Lythrum salicaria). This is just a partial list of
invasive species that were observed. For more information and sources to identify invasive species
contact a professional, the Minnesota Department of Natural Resource,
www.dnr.state.mn.us/invasives/index.html or Minneapolis Parks and Recreation,
www.minneapolisparks.org.

Low Diversity
Typically when areas have been affected by prolonged periods of erosion, pollution, or invasive
species, diversity of flora will be low, which often leads to low diversity of fauna. As with
invasive species, depending on the level of pollution or erosion present, native species can also
form single species stands. This condition of low diversity should be avoided. By the time this
condition is usually noticed a site restoration may be needed.

8

What is Working Along the River
Rivers, as well as the land adjacent to them, are in a constant state of flux with rising and dropping water
levels from rainfall, snow melt, and dams, and with varying levels of sediment load. The system that has
evolved along the river is able to adapt to changing conditions. Plants have evolved to handle extended
durations of flooding as well as dry periods. The river’s banks are constantly changing themselves by
slumping or stabilizing with the growth of new plant material. Along the Mississippi River there are areas of
natural stabilization; areas where traditional stabilization efforts have been undertaken; and areas where
restoration efforts utilizing bioengineering have been undertaken.

Natural Stabilization
Riverbanks naturally stabilize themselves through various methods. A natural stabilized river
bank is the result of many factors including proper vegetation, slope, soil type, river current,
amount of erosion, and flooding frequency. These are just some factors that affect the appearance
of a naturally stabilized river bank. There is a balancing act going on along the river banks and
the absence or addition of any of these factors will effect how the bank responds. Those naturally
stabilized banks along the Mississippi River have arrived at this delicate equilibrium.

Along the Mississippi River within the MWMO boundaries, are examples of intact plant
communities. These areas are largely intact because they have been incorporated into park lands.
The plant communities would typically be classified as floodplain and riparian communities.
Plants in these areas are adapted to occasional flooding and moist soils. The root systems that
have been created are able to confine and stabilize the soil. These areas are threatened by
populations of invasive species that occur along the river. In some areas, invasive species have
begun to establish an influential presence within native community remnants.

Traditional Stabilization Efforts
Stabilization efforts that use hard armoring with no vegetation are sometimes necessary in limited
locations along the river to protect transportation infrastructure and buildings, to maximize
riverfront land use while maintaining channel width, and to provide boat tie-up locations. One
example is, north of downtown, in the industrial area where there is a need to have a vertical bank
for the mooring of barges.

Restoration Efforts
There are several examples along the Mississippi River of various restoration and stabilization
efforts. At this time, the majority of restoration efforts along the Mississippi River are overseen
by Minneapolis Park and Recreation Board. There are newer installations along Sheridan
Memorial Park, West River Road and North Mississippi Park.

9

Steps to a Successful Project
Assessing and classifying a site are just the first steps in a restoration or stabilization along the Mississippi
River. Once an assessment is completed and potential practices are decided upon, implementation
mechanisms can be employed. This includes a closer analysis of the site, project cost, design, permitting,
purchasing supplies, hiring a contractor, and maintenance. These steps are necessary to fulfill the site
objectives for a successful project.

Analyzing the Site
Appendix D: Riverbank Assessment Sheet. This is a copy of a riverbank assessment sheet used
in the field while assessing the Mississippi Riverbank. The sheet is provided as a reference as
well as a resource for landowners to complete their own assessment of their reach of the river.
Three sheets need to be filled out per observation; one for each zone of the riverbank.

Assess Site for Signs and Sources of Erosion
What to look for:
Steep slopes with highly erodible soils
Bare eroded soil with no vegetation
Sloughing soil
Uprooted or fallen trees
Rills or gullies caused by rainfall
Undercut bank

How bad is it:
Is there considerable soil loss from erosion or
sloughing? Sloughing Soil
Have many trees been toppled and need to be Dan Kalmon
removed?
Have invasive species moved in and need to
be treated?

Do-it-Yourself or Bring in a Contractor
Access the Riverbank Restoration Planning
Software to determine the appropriate practice(s)
for your site. Look over the technical sheets for
the practice(s) in the manual or via the riverbank
restoration planning software. Some practices
may require heavy machinery, special equipment,
or technical training to install. If this is the case, a Uprooted and Fallen Trees
contractor may need to be consulted for the Dan Kalmon
installation. Also a contractor may want to be
considered if the riverbank is too steep to access from land and supplies need to be brought in
from the river.

10

Using background and research materials
This manual’s appendix as well as the Riverbank Restoration Planning Software’s detailed field /
model data section both contain a breadth of supporting information to further aid riverbank
restoration efforts. Reference to appendices, web sites, and web links are given in this manual’s text
to allow the user to pursue a more thorough understanding of the particular topic and to provide
more tools for the user to access.

Identify zones
The most important point on the bank to identify is the level of bankfull. Generally, everything
below bankfull is frequently subjected to heavy flows of water. A bank crest may be present at
bankfull. The crest is generally a sharp break in the slope at the level of incipient flooding. Possible
indicators of this level may include (this list modified from USACE 1997):
The elevation of incipient flooding, the height at which water will flow into the surrounding
floodplain.
The elevation associated with the top of the highest depositional features (e.g., point bars,
central bars within the active channel). These depositional features are especially good stage
indicators for channels in the presence of terraces or adjacent colluvial slopes.
A break in slope of the banks and/or a change in the particle size distribution, (since finer
material is associated with deposition by overflow, rather than deposition of coarser material
within the active channel).
Exposed root hairs below an intact soil layer indicating exposure to erosive flow.
Lichens and, for some stream types and locales, certain riparian vegetation species. A change
in species composition may also indicate the bankfull level.

Review the section Assessing Riverbank Zones, pg .
See Appendix G: Understanding our Streams & Rivers, MnDNR
The USDA Forest Service also has online videos on identifying zones of the river.
ww.stream.fs.fed.us/publications/videos.html

Identify soils
Appendix E: Soil Classification has images of cards for identifying both soils and gravels.

Identify vegetation cover percentage
Appendix F: Vegetation Cover Percentage has images of various cover percentages as viewed
during the team’s assessment of the Mississippi Riverbank.

11

Determine if assessment is feasible
It is generally best to assess and classify the riverbank during periods of low water levels. Late
fall and winter are good times to assess and classify (provided snow does not cover the bank)
because reduced leaf cover helps to expose more of the bank substrate. As a general rule, the river
level should be at or below average flow rate (normal water level) or gauge height to perform this
assessment. If the river flow is above average or no gauge data is available, the following must be
true to get an accurate assessment of the whole river bank:
The river level must not be at or above bankfull
If there are any scarps, the entire scarp must be visible above water
A reasonable portion of the splash zone must be visible (enough to determine the slope
below the scarp and identify the surface material)

River Level Gauge Information
US Army Corps of Engineers river levels for the Upper Mississippi
Minneapolis , MN to Guttenberg, IA:
www.mvp-wc.usace.army.mil/imagemaps/Miss.shtml

A more site specific analysis should be conducted to collect additional information. The soil and sun
orientation (aspect of slope) should be checked and noted. This will help to understand the type of
vegetation that is appropriate for the site. The slope of the bank and slope of the upland should also
be quantified to help determine the appropriate practices to implement. It is also important to do a
visual assessment to identify the location of the transition of the toe/slope, bank, and upland.
Additionally, the approximate OHWL location determines if the site falls within the jurisdictions of
the Minnesota Department of Natural Resources (MnDNR) (anything below the OHWL is property
of the state). The site specific analysis is important, since it allows for a better understanding of the
site.

12

Project Costs
River bank restoration techniques can vary widely in price. The difference in price reflects the
complexity of the project, site accessibility, permitting, and whether large machinery is needed to
complete the project. Below are rough cost estimates for the various practices included in this
manual with costs adjusted for 2008. Having a project installed by a professional will typically double
or triple the cost of a project in the short term, but may actually save money in the long term.

Do-it-yourself cost Installed Cost
(Material and Labor)
Restoration and Stabilization Practices
Seed $20 per 1000 square feet $170 per 1000 square feet
Planting $1.25 per plug $2.5 - $3 per plug
Erosion blanket with planting .78¢ per square foot $1.80 per square foot
Bio-logs $5-$10 per lineal foot $15-$20 per lineal foot
Live Stakes $1 -$3 per stake $3-$8 per stake
Live Fascine $2.5 per lineal foot $13 per lineal foot b
Brush Mattress $1.3 -$3.9 per lineal foot a $12 - $20 per lineal foot a
Tree Revetment N/Ad $35 per lineal foot
Vegetated Geogrid N/Ad $20 per square foot b
Rootwads N/Ad $450 - $1,500 per Rootwadc
Crib walls N/Ad $260 per lineal foot
Riprap N/Ad $65 -$118 per lineal foot a
Gabions N/Ad $30 per square foot
Retaining Walls N/Ad $50 per square foot

Erosion Control Measures
1’-2’ Compost Berm N/Ad $2.75-$3.3 per lineal foote
12” Compost Filter Sock N/Ad $3.15 - $3.7 per lineal foote
3’ Silt Fence .75¢ per lineal foot $2.20 - $3 per lineal foote

Site Improvement
Site Grading N/Ad $15-$30 per cubic yard

a Adapted from Henderson, Carol L., Carolyn J. Dindorf, Fred J. Rozumalski. 1998. Lakescaping for Wildlife
and Water Quality. Minnesota Department of Natural Resources, St. Paul, MN. Costs were adjusted for
inflation to 2008.
b Adapted from The Kestrel Design Group. Minnesota Soil Bioengineering Handbook. Minnesota
Department of Transportation, St. Paul, MN. Costs were adjusted for inflation to 2008.
c Data provided by MnDNR. Cost provided is that the site is fairly open with only shrubs and small trees on
site.
d The installation requires the use of heavy machinery or special equipment consult with a contractor for
installation.
e Adapted from Schwab, Jean. 2006. Erosion Control Alternatives Cost Calculator. United States
Environmental Protection Agency, Green Scapes.
http://epa.gov/epawaste/partnerships/greenscapes/tools/erosion.pdf. Costs were adjusted for inflation to
2008. http://epa.gov/epawaste/partnerships/greenscapes/tools/erosion.pdf.
f Cost were adjusted for inflation to 2008.
Inflation Source CPI Inflation Calculator. http://data.bls.gov/cgi-bin/cpicalc.pl

13

Design
Start with the riverbank restoration planning software to identify possible restoration solutions. Next
consult with qualified professionals to design or review your project’s design. Improperly designed
projects can lead to failure and additional expenses later. A final design should include an erosion
control plan, grading plan as needed, planting plan, and maintenance plan.

Erosion Control Plan:
This is a plan that includes all measures that will be taken to control erosion and sediment loss during
the construction period. See Appendix I: Minneapolis Regulations. Other resources:
www.ci.minneapolis.mn.us/stormwater/classroom-resources/erosioncontrollinks.asp
City of Minneapolis’ web site with links to other information and agencies.
www.metrocouncil.org/environment/Watershed/bmp/manual.htm
Metropolitan Councils Urban Small Sites Best Management Practice Manual which has a
section on erosion control practices

Grading Plan:
Usually included as part of the erosion control plan, this may or may not be needed depending on the
practice(s) being implemented. The grading plan will show the existing grade and what the proposed
changes will be to the grade.

Planting Plan:
A planting plan gives specific instructions about how the soil is to be prepared, what species are to be
planted, what size plants are to be used, and what the spacing of plants should be. The planting plan
will also contain a plant schedule with a list of all the plants and total plant counts.

Maintenance Plan:
This can be included on the planting plan or separately. It typically lays out the maintenance
requirements for installed practices and vegetation, as well as a schedule of specific maintenance tasks
and when they need to be accomplished.

There is a limited window of opportunity for implementing restoration practices along the
Mississippi River, which can vary from year to year. It is best to consult with a professional at the
end of the year or early in the project implementation year. This allows for the design to be drawn
and measurements to be taken while the water level is low. There is usually a stretch of time in
spring and early summer when river levels are too high to implement restoration projects. This is a
good time to be finalizing the design and begin preparing for installation. While planning the scope
of the project it is also a good time to layout what phases the project will be installed. This will help
to understand which and how many erosion control measures need to be considered, as well as the
timing of their implementation.

All efforts should be made to properly stabilize slopes, so as to prevent further degradation to the
site. Steps should be taken to make sure restoration is done properly to lessen the chance of having
to redo the project. This includes proper selection of bioengineering materials and installation time.
Other steps should be taken to manage the site during installation so that erosion and sedimentation
to the river are kept at a minimum. Erosion and sedimentation control can be achieved through
both perimeter and interior controls, which may include the use of silt fences, temporary bio-logs,
temporary ground cover, temporary seeding, check damns, and sediment catch areas.

14

Permitting
Before beginning or attempting to install any restoration of a riverbank, check with the necessary
governing bodies. Many times restoration along water bodies is regulated by federal, state, and local
authorities and programs. This overlapping of regulatory jurisdictions is a way of maintaining and
protecting natural resources for generations to come (NRCS 2007). For any type of restoration work
along the Mississippi River within Minneapolis it is best to start with Minneapolis Development
Review. For site projects over one acre Compliance with Chapter 54 of the Minneapolis Code of
Ordinances Stormwater Management must be met. This includes providing a stormwater
management report that includes design details of all BMP’s, calculations, inspection, operations
and maintenance plans, www.ci.minneapolis.mn.us/stormwater/fee/requirements_chapter54.asp.
(see Appendix I).

Minneapolis Development Mississippi Watershed Management
Review Organization
250 S. 4th St., Room 300 2520 Larpenteur Ave W
Minneapolis, MN 55415 Lauderdale, MN 55113
(612) 673-2352 (651) 287-0948
www.ci.minneapolis.mn.us/mdr/ www.mwmo.org

Minnehaha Creek Watershed Shingle Creek Watershed Management
District Commission
18202 Minnetonka Blvd 3235 Fernbrook Lane
Deephaven, MN 55391 Plymouth, MN 55447
(952) 471-0590 (763) 553-1144
www.minnehahacreek.org www.shinglecreek.org

For any part of a project affecting the area below the OHWL, a permit may be needed. Typically in
Minnesota, this area of water bodies is overseen by the Minnesota Department of Natural Resources
(MnDNR) for both state and federal permits. Usually bioengineering practices do not require
permit, but approval is still needed as long as the project is installed by hand for the purpose of
shoreline restoration work if:
Project is approved by MnDNR staff and is designed or reviewed by the county environmental
services, local soil and water conservation district or the local watershed management
organization.
Design does not interfere with navigation or other riparian uses of the waterbody.
Project is done during times of the year when it will not interfere with fish spawning or the
nesting of protected bird species.
Local origin native plant species, adapted for the site, are used.
Aquatic plant management permit is obtained when aquatic plants are used.
Waterward encroachment is the minimum necessary for the project; and a maintenance plan is
developed for the project and a copy submitted for Review to the Department's Area Fisheries
office (MnDNR, 10/9/08). www.dnr.state.mn.us/permits/water/answers.html#shorelinerestoration

MnDNR Waters
1200 Warner Road
St. Paul, MN 55106
(651) 259-5845
http://files.dnr.state.mn.us/waters/area_hydros.pdf

15

If any part of a restoration affects the navigable waters of the Mississippi River a permit from the
United States Army Corp of Engineers must be obtained.
www.usace.army.mil/cw/cecwo/reg/reg_faq.htm

Construction
Even though bioengineering and riverbank restoration are becoming more accepted, not all
contractors are experienced with the proper techniques for installation. Contractors need to be
aware of how and when the river level typically fluctuates and when the best time of year is to install
plants along the river. Typically rivers are high in the spring after snow melt and spring rains. This
leaves late May and June as a good time for installation otherwise it is best to wait until the weather
has cooled and plant in the fall. Some suppliers of native plants and supplies have been included in
Appendix H.

If a project needs to be hired out to a designer or contractor, make sure to ask to see examples of
their work as well as customer references. Don’t hesitate to follow up and check some of the
references to see what the outcome was of their project and how things went while establishing.
Riverbank restoration is a rather narrow field of expertise, and may require looking for someone who
also specializes in lakeshores and wetland restoration. Make sure to ask them questions to see if they
are qualified to complete the work being asked of them, for example:
Have they installed or designed a river restoration before?
Three references of completed projects and can they be visited?
What is their background in river bank restoration?
What extent are native plants used in their river bank restorations?
Where do they purchase their native plants and supplies from?

Maintenance
A follow up maintenance and monitoring plan is key to a successful installation. Maintenance is
necessary to ensure the objectives of the project are attained. The maintenance plan for each project
should be flexible to respond to conditions monitored on site as they arise. This flexibility is
important, as rivers are ever-changing systems and conditions will fluctuate from year to year.

With bioengineering practices, follow up maintenance and monitoring is especially important. These
projects rely on vegetation to become well-established before a major disturbance event occurs, such
as high water. If a major event does occur, it may be necessary to inspect the practice and reinstall
vegetation in areas where flooding occurred.

16

Case Studies

Slope Restoration, St.Croix River, Lakeland, MN

This private residence, located along the St. Croix River, required
a hillside restoration in order to heal the eroding slope. A
previous owner had installed concrete block on the upper half of
the slope with a concrete wall at the bottom. Both areas were in
decline as the concrete was deteriorating. At the same time, roof
runoff ran across the concrete slope causing eroded soils to drain
directly into the St. Croix River.

After consulting with an engineer, the project manager and owner
agreed that the concrete needed to stay in place to protect the
Bio-log installation
building foundation. The solution as proposed by the engineer Todd Rexine
was to bring in soil, bio-logs, and large outcroppings to bury the
concrete and reestablish the slope. Once the soil was in place,
technicians installed erosion control blankets. The site was then
planted with a diversity of appropriate native plants and shrubs to
create a root structure that holds the soil in place. Planting above
the concrete blocks allows the native plants to send roots through
the cracks in the concrete and anchor into the pre-existing soils.

Upon completion the property owner purchased a pump that
could be placed in the river to help irrigate all the new plantings
while they were establishing. A water use (appropriation) permit Erosion control blanket & plantings
from DNR Waters is required for all users withdrawing more than Todd Rexine
10,000 gallons of water per day or 1 million gallons per year
(MnDNR, 12/12/08).
www.dnr.state.mn.us/waters/watermgmt_section/appropriations/permits.ht
ml

The images at right are in progression from initial installation to
one year later.

2 month follow up
Jay Riggs, WCD

1 year follow up
Sally Arneson-Scallon

17

Bank Restoration, Vermillion River, Hastings, MN

This is a bank restoration for a private residence that abuts the
Vermillion River in Hastings, MN. The property is located along
an outside bend in the river with an eroded bank. The bank is
approximately 30 feet in height with a steep slope and very sandy
soils. Sloughing was occurring along 150 feet of the mid-section
of the bank due to an absence of vegetation, this in turn, led to
smothering the vegetation in the lower portions of the bank.

To address the bank erosion issues multiple restoration
techniques were implemented along the 150 feet of river bank. Pre-existing streambank
The plan incorporated a double layer of cedar tree revetments at Great River Greening
the toe of the bank. Above the revetments native shrub-willow
fascines, live shrub-willow stakes, and erosion control blanket
with native seed were installed in strips across the middle portions
of the bank.

The seed, live fascines and stakes will root into the bank soil
providing a structure to hold the soil in place. The revetments are
in place to help stabilize the toe and control cutting of the bank
from the current. Playing a dual role, the cedar revetments will
also help capture any additional soil that sloughs from the bank
while vegetation is establishing. In this situation, using rip rap
alone would most likely fail, since the bank soil is so steep and
highly erodible.

Pre-existing streambank

Stabilized Bank

18

Toe Restoration, St. Croix River, Lake St. Croix Beach, MN

The toe of the slope at this residence on the St. Croix was heavily
eroded due to flooding of the St. Croix River in the late 1990’s.
The flooding caused undercutting of trees which have since
toppled. Buckthorn and exotic honeysuckle have easily invaded
this disturbed area, shading out understory growth. The overall
cumulative affect on the soil erosion of the site goes beyond just
the flooding in the late 1990’s.

The approach to stabilizing the slope had multiple phases. The
first phase was to berm the top of the slope and vegetate it with Pre-existing Riverbank
native plants. This was an effort to slow rain water down and Great River Greening
allow it to infiltrate into the very sandy soils. Next step was to
clear the upland potion of the bank and complete an oak savanna
restoration, which required that six mature red cedars were
removed to allow sunlight into the understory. In place of the
cedars, four bur oaks were planted on the slope.

The toe of the slope was the last phase to go in. This required a
more engineered approach to stabilizing the slope. Starting at mid
slope and working down every 5 feet some form of revetment
was installed per an engineer’s specification. The revetments were
a combination of cedar logs, brush wattles and bio-logs. The Pre-existing Riverbank
revetments were anchored in using a cable anchoring system. The
system required driving an anchor 3 feet into the ground. The toe
also had erosion fabric installed which was seeded with native
grasses. The toe area was also planted with various native bare
root shrubs and trees.

Toe Installation
Todd Rexine

Completed Toe Installation
Todd Rexine

19

20

Technical Sheets: River Bank Restoration Solutions

Riverbank restoration can be achieved
through a wide array of practices. The
proper technique(s) dependant upon the
specific conditions and circumstances
associated with a given site. Frequently,
practices are combined to form an effective
package of treatments to address several
issues playing out at a given site. In the
following pages, several practices have been
detailed, ranging from soil bioengineering
solutions to more complex hard armoring
systems. These practice reference sheets are
intended to familiarize readers with some of
the practices employed to address riverbank
restoration.
St. Croix River, Lake St. Croix Beach, MN.
Fascines, coconut rolls (bio-log), seeded erosion blanket
Todd Rexine

Vermillion River, Hastings, MN.
Tree revetments, erosion blanket, and live staking

NOTICE: The Mississippi Watershed Management Organization, Great River Greening, and LimnoTech Inc are not
liable for damages or losses that may result from the installation of any of the recommended practices in this guidance manual.
It is the landowners’ responsibility to assure that the practices installed on their sites do not result in damages or losses to
persons or property. This guidance manual provides a range of restoration options for various sites based on a generalized
classification of the riverbanks within the MWMO. It is meant to provide landowners with a list of potential riverbank
restoration practices. Landowners must conduct any analysis needed to determine which of these practices, if any, are suitable
for installation on their sites given site specific characteristics.

21

22

Technical Sheet 1: Vegetated Erosion Control Blanket

Summary
Vegetated erosion control blankets are used for temporary soil stabilization to aid in establishing plants in
areas with exposed soils or slight erosion problems.

Max Shear Stress Maximum Slope Substrate not Minimum Site
recommended to be Disturbance
installed beyond Width
4 lb/ft2 2:1 Gravel 6 ft
1915.2 dyne/cm2 Installation Zones Vegetation Density Minimum Vertical
Slope Width
Required
Upland 76-100% 6 ft

Advantages
Relatively inexpensive and Erosion blanket Herbaceous
quick to install. key into soil at top plugs or seed
This is a soft installation and
can be combined be used in
conjunction with other 100 yr flood
practices especially where river
currents exhibit higher stresses.

Disadvantages
May be dislodged by high
water levels prior to vegetation 6” U-staples or spikes
establishment. Minimum 2-3 ft on center
12” spacing on top, bottom and sides
Installation
Gently grade the slope.
If using seed, broadcast it
over the prepared bed and
lightly rake in, prior to
placement of blanket.
Dig a shallow 6 inch wide by
6 inch deep trench along the
top of the slope.
Place the top edge of the
blanket in the trench; secure
every 12 inches and backfill.
This will prevent overland
runoff from undermining the
blanket.
Unroll the blanket over the
bed and anchor using staples
or other stakes to anchor the
blanket every 2 – 3 feet on
center in a diamond pattern. St. Croix River, Lakeland, MN.
Erosion blanket and native plugs
Todd Rexine

23

Staple the top, bottom, and sides
every 12 inches minimum. 12” spacing across top
Erosion blanket should always be
“shingled” by having blankets
upstream or uphill overlapping 2-3 ft spacing in
those downstream or downhill diamond pattern
(overlap should be at least 12
inches).

Plugs can easily be planted into the
blanket by cutting a small hole in the
blanket to expose the soil below. When
selecting plants, whether nursery grown 12” spacing along sides
or seed, it is important to understand the
light conditions and soil of the site, since
Stapling pattern for erosion fabric
this will dictate what the moisture
conditions and shade tolerances that
plants will encounter. This will help in choosing proper plants and lead to a much better success rate,
especially in the long term.
For a list of possible plants and other reference materials for plants see Appendix B: Plants.

Management
New plantings will be stressed and require watering to aid in establishment. When plants are first installed,
they will require watering at a minimum every 2 -3 days for the first 2 months. After the first 2 months
watering should be cut back to 1 inch of water per week for the rest of the first year. Long soaking waterings
are better than short ones as they encourage roots to grow downward into the soil. If possible, it is
recommended that a sump pump be purchased and placed in the river to facilitate the watering of the new
plantings.

The area should be monitored, especially following any high water events. Repairs should be made as needed
and additional vegetation planted.

Bibliography
Tuttle, Ronald W. and Richard D. Wenberg. 1996. “Streambank and Shoreline Protection.” Engineering
Field Handbook, Chapter 16. USDA-NRCS.
http://www.info.usda.gov/CED/ftp/CED/EFH-CH16.pdf

24

Technical Sheet 2: Bio-logs

Summary
Bio-logs are used for temporary soil stabilization to aid in establishing plants in areas with exposed soils or
slight erosion problems. The logs are typically made out of coconut fiber, rice wattle or wheat wattle.

Shear Stress Maximum Slope Substrate not Minimum Site
recommended to be Disturbance Width
installed beyond
5 lb/ft2 2:1 Cobble 10 ft
2394 dyne/cm2 Installation Zones Vegetation Density Minimum Vertical
Slope Width Required
Toe/Splash, Bank, 51-75% 1 ft
Upland

Advantages
Relatively inexpensive and quick to install.
This is a soft installation and can be combined
be used in conjunction with other practices
especially where river currents exhibit higher
stresses.
Biologs are fairly lightweight.
Biologs can conform to the contours of the
bank/toe.
Biologs are bio-degradable, and decompose in 3
to 7 years for coconut fiber, and 1 to 3 years for
wood fiber, depending on density of Bone Lake, Scandia, MN.
packing. Coconut fiber roll (bio-log) with herbaceous plugs
Todd Rexine
Disadvantages
May be dislodged by high water levels prior to vegetation establishment.
High wave-action may cause loosen anchored
Biologs are fairly bulky.

Installation
Dig a shallow, 2 inch trench at the base of the slope.
Place the bio-log in the trench so the backside is tight against the slope.
Stake in place using two, 4 foot long wood stakes at each end and alternating sides every 1 foot on
center.
Secure in place with rope or wire tied to stakes and drive stakes flush with top of log.
Cut the slope to fill the backside of the bio-log with soil up to 2 inches from the top.

One month or more after installation (or when biolog is saturated), plant plugs into the bio-log, spacing every
12 inches. This will enable sediment to collect, ensuring a high survival rate. If logs are placed in water,
planting can occur immediately after installation

25

Existing vegetation or
bioengineering practice
Herbaceous
plugs

Bio-log Bankfull

Normal Water
Level

2”x2” x 3 - 4’ wood stake
install 1’ on center
alternating sides. Install 2
stakes on each end. Tie
coir rope to stakes and
finish driving stakes in.

Management

Bibliography
Eubank, C. Ellen and Dexter Meadows. A Soil Bioengineering Manual for Streambank and Lakeshore
Stabilization. USDA-Forest Service

http://www.info.usda.gov/CED/ftp/CED/EFH-CH16

26

Technical Sheet 3: Live Stakes

Summary
Live staking is a technique to quickly and easily establish woody vegetation in areas with high moisture.

recommended to be Disturbance
installed beyond Width
3.1 lb/ft2 2:1 Gravel 6 ft
1484.28 dyne/cm2 Installation Zones Vegetation Density Minimum Vertical
Slope Width
Required
Bank and Upland 76-100% 1 ft

Advantages
Allows river bank to revegetate.
This is a soft installation and can be combined be used in conjunction with other practices especially
where river currents exhibit higher stresses.

Disadvantages
May be dislodged by high water levels prior to vegetation establishment.
Difficulty finding enough plant material on site.
Timing: stakes should be dormant, so work must be conducted either in spring of fall, which may be
difficult.

Installation
Live stakes can be cut from willow,
dogwood, or other woody species (see Triangular spacing
appendix B) that readily resprout from 2-3 ft apart
cuttings. Stakes should be cut from
dormant plants either after dropping leaves
or before budding. This is typically after
Bankfull
November 1st to the middle of March.
Live stakes should not be installed after
frost has set in the ground. Live stakes can
also be refrigerated and installed during the Normal Water
growing season; spring or fall.
Stakes should be from ½ inch to 1
inch in diameter and 3 – 4 feet in
length. Basal end
Live stakes should be installed Live cuttings ½” to 1” in diameter.
same day they are prepped. Cut end of stake at 30° - 45°.
Before planting the basal end of the
stake should be cut diagonally to 30°- 45° and dipped in a rooting hormone.
Install stakes 2 - 3 feet apart. Gently pound into soft ground, using a dead blow hammer or rubber
mallet, or place in a preformed hole so that 2/3 of the stake is buried. In more compacted soils
holes can be dug using a small auger or water jetting.
Be sure not to split the stake when planting and that the basal end is placed in soil.

27

Stakes should be planted in an offset pattern so when viewed from top or bottom they form a
diamond pattern.
Minimum soil depth is 2 feet for rooting into soils. Live stakes can be installed either vertical, horizontal or at
an angle. Live stake trees typically are installed either vertical or at a slight angle.

Management

Bibliography

Henderson, Carol L., Carolyn J. Dindorf, Fred J. Rozumalski. 1998. Lakescaping for Wildlife and Water
Quality. Minnesota Department of Natural Resources, St. Paul, MN.

The Kestrel Design Group. Minnesota Soil Bioengineering Handbook. Minnesota Department of
Transportation.


28

Technical Sheet 4: Live Fascines

Summary
A bundle of live cuttings tied together with rope and placed in a shallow trench.

installed beyond
3.1 lb/ft2 2:1 Gravel 8 ft
1484.28 dyne/cm2 Zones of Impact Vegetation Density Minimum Vertical
Bank and Upland 76-100% 1.5 ft

Advantages
This is a soft installation and can be combined be used in conjunction with other practices especially
where river currents exhibit higher stresses.

Disadvantages Erosion control
May be dislodged by high blanket & native seed
water levels prior to or planting
vegetation establishment. Bankfull
Installation
Fascines are bundles of
live cuttings (see appendix
B). Normal Water
Cuttings are harvested
under the same conditions
Top of live fascine
as live stakes, however
slightly exposed after
cuttings should be 5 to10
installation
feet in length. Stake spacing
Tie the cuttings into 10 2-3 ft
to12 inch diameter bundles
staggering the cuttings
throughout the bundle Live End Basal End
with the live ends all facing
one direction.
Excavate a trench 2 inches
wider than the finished
bundle.
Place fascine bundle in the Current
trench and secure in place 18” overlap
with a 3 foot dead stout
stake.
The live end of fascines should overlap the basal ends of the previous fascine by 18 inches.
Once all the fascines are staked in place the trench may be backfilled.

29

Recommended Live Fascine Spacing
Slope Steep Eroded soils Non-eroded soils Fill soils
3:1 or flatter 3-5ft 5-7ft 3-5ft *
Steeper than 3:1 3ft* 3-5ft -
*practice not recommended alone

Adapted from: Tuttle, Ronald W. and Richard D. Wenberg. 1996. “Streambank and Shoreline Protection.”
Engineering Field Handbook, Chapter 16. USDA-NRCS.

Management

Bibliography

Hoag, Craig and Jon Fripp. 2002. Streambank Soil Bioengineering Field Manual for Low Precipitation
Areas. USDA-NRCS.
http://plant-materials.nrcs.usda.gov/pubs/idpmcpussfglpa.pdf


30

Technical Sheet 5: Brush Mattress

Summary
Use a combination of live cuttings and live stakes. Branches from species such as dogwood or willow are
secured against bare soil to create a dense mat of live brush. Live brush can be mixed with other brush, such
as buckthorn or honeysuckle from an invasive species removal. Soil is placed over the cuttings (or allowed to
fill in over time with sedimentation). The cuttings will sprout to create a dense network of roots and stems to
stabilize the soil

Max Shear Stress Maximum Slope Substrate not Minimum Site
installed beyond
4.1 lb/ft2 (initial) 2:1 Gravel 8 ft
8.2 lb/ft2 (grown)
1963.08 dyne/cm2 (initial) Zones of Impact Vegetation Density Minimum Vertical
3926.16 dyne/cm2 (grown) Slope Width Required
Bank and Upland 76-100% 10 ft

Advantages
Low cost to install.
Good utilization of on-site shrubs.

Disadvantages
Locating enough brush on site or a donor site
close by.

Installation
Grade the site to a slope of 2:1 or less.
Clear the site to bare soil to ensure that proper
soil contact is achieved.
Harvest live cuttings (see appendix B) after Sheridan Memorial Park, Minneapolis, MN.
they have gone dormant or before budding in Brush Mattress
Nick P Eoloff, MPRB
the spring. Twenty percent of the cuttings
can be dead to add bulk to the mattress.
Cuttings should be ½ -1 inch in diameter and from 5-10 feet in length. Shorter cuttings will not be
secured properly and should be avoided.
Dig a shallow trench at the bottom of the slope, (do not extend into toe zone).
Place the cuttings vertically against the slope with the basal ends placed in the trench.
Place 2 layers of cuttings over the slope so that no gaps remain.
Drive in live and/or dead stakes halfway every 2-3 feet throughout the mattress area.
Tie rope between the stakes to create a “spider web” pattern.
Drive the stakes in bit by bit so that they all go down relatively simultaneously, until the mattress is
tightly secured against the bank.
Place a live fascine in the trench along the bottom of the slope and secure in place using stakes.
Cover the mattress with a thin layer of soil so that 1/3 of the branches are visible. This will allow
some branches to sprout leaves and some to grow roots.

31

Management
The area should be monitored, especially following any high water events. Repairs should be made as
needed. Additional brush should be added and secured in place as needed to allow for bank stabilization.

Add live fascine
last over brush
ends
Bankfull

Normal Water

Dead stout
stakes to be at
least 2 ft into
ground

Top View

Rope secured
to stakes

Dead stout
stakes 2-3 ft on
center
Basal end of
branches down
Live fascine

32

Bibliography

Hoag, Craig and Jon Fripp. 2002. Streambank Soil Bioengineering Field Manual for Low Precipitation
Areas. USDA-NRCS.
http://plant-materials.nrcs.usda.gov/pubs/idpmcpussfglpa.pdf

The Kestrel Design Group. Minnesota Soil Bioengineering Handbook. Minnesota Department of
Transportation.


33

34

Technical Sheet 6: Tree Revetments

Summary
Cedar or other brushy trees are anchored to the stream bed at the toe of the slope. They slow velocity along
the stream edge and collect sediment to rebuild the bank.

installed beyond
*3.9 lb/ft2 N/A Boulder 15-20 ft
*1867 dyne/cm2 Zones of Impact Vegetation Density Minimum Vertical
Toe/Splash and 10-25% 3 ft
Bank
* Estimated shear stress based on brush mattress. Actual max shear stress still to be
determined.

Advantages
Easy and inexpensive to install.
Reduces velocity along bank.
Collects sediment and debris to rebuild bank.
Good utilization of existing red cedar/trees

Disadvantages
Not appropriate for sites with loose disturbed soil.
Can appear messy at high visibility sites.
Availability of trees close to the installation site.
Should not be installed close to structures, such as bridges, where dislodged revetments from high
water could cause damage or blocking of river.
Will not root into soil

Installation
Collecting and preparing trees:
Trees used should contain many branches. 10-15 feet tall trees work well as they have enough bulk but are
manageable to move by hand. Sparse trees will not hold sediment nor create enough friction to be effective.
Branches from one side should be removed to allow the trunk to sit tight against the bank. Approximately ¼
of each tree will overlap the downstream tree so a 20 foot bank will need 25 feet of trees harvested.

Installing:
Installation should begin on the downstream end and move upstream with the top of the trees
pointing downstream.
The first tree is anchored by installing an earth anchor system such as a Duckbill™ or screw-type
earth anchor two feet from the top of the tree.
The anchor is driven into the bank at a 45 degree angle far enough so that the cable is tight and the
tree will not move.
A second tree should be placed upstream so that the top of the upstream tree overlaps the base of
the downstream tree by 3 feet.
A second earth anchor is cabled around the two trees and driven into the ground.
Continue working upstream.

35

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