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Table 1-1. Examples of Instream, Riparian, and Upland Restoration Techniques
Restoration
Category Description
Instream Reconfiguration of stream bed: Dig a new channel for
stream beds that have become braided or overly
shallow. The new channel should increase depth and
structural complexity (thalweg cross section).
Instream Restoration of channel course natural meander pattern:
Remove any manmade structure or stop dredging
practices that maintain channelization; actively
redirect stream into meander pattern appropriate to
hydrologic conditions.
Instream Root wad/tree revetment: A stump with roots still
attached is placed horizontally into the stream bank
with the root end extending into the stream.
Instream Live stakes, live fascines, brush mattresses, branch
packings, brush layering, vegetated geogrids, and live
cribwall: These are all stream bank stabilization
techniques that use vegetation bundles (e.g., willows)
placed in stream banks in various patterns and means
of attachment. A particular method is selected based
on soil type, bank slope, and hydrologic conditions.
Instream Channel deflector and channel constrictor: Deflectors
and constrictors are triangular-shaped structures,
constructed from rock, gabion, or logs that extend
into the stream to narrow and deepen streams in
selected locations. These techniques encourage
meander, form pools, increase cover, and protect
eroding banks.
Instream Boulder cluster: Large boulders are placed
strategically in the stream channel to increase
structural complexity, including eddies and small
pools.
Instream Log drop structure: This example is one of many
structures that alter flow conditions to create small
drops and pools. The log drop consists of a log
placed across the stream, with a V notch cut into the
middle to direct flow. Characteristics of these
structures (e.g., height of the drop and width of the
log) are carefully designed to prevent the obstruction
of fish migration.
Riparian Wetland restoration
Riparian Re-establishing vegetation in the riparian corridor
with native species best suited to current hydrologic
and soil conditions (e.g., forested riparian buffers).
Riparian Controlling the timing, location, and extent of water
diversions from and irrigation return flows to stream
channel.
Riparian Constructing fences and gates in riparian corridor to
control access of grazing livestock and other
agricultural activities to selected locations along
the stream.
Upland Urban BMPs: Retention devices (e.g., infiltration
basins, trenches, dry wells, and porous pavement);
vegetative controls (e.g., basin landscaping, filter
strips, grassed swales, and wetlands); source controls
(e.g., education regarding inappropriate discharges to
storm drains and proper disposal of potential
contaminants); erosion control (e.g., construction
site management and controls); land-use planning
(e.g., limiting direct connection of impervious area
to waterbody); sewage overflow controls; urban
stormwater retrofits.
Upland Agricultural and grazing BMPs: Erosion and sediment
control(e.g., filter strips, grassed waterways, and
conservation tillage); confined animal facility
management (e.g., sediment basins); grazing management
(e.g., livestock exclusion, alternative drinking
locations, and stream crossings).
Upland Forestry BMPs: Streamside management areas that
contain canopy species to control temperature and
increase bank stability; road decommissionings;
erosion control (e.g., grass-seeding, hydromulch,
installation of road drainage structures such as
water bars, dips, or ditches).
Upland Point source effluent controls
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