September Issue of the Texas Water Source Now Available
Thursday, September 1, 2011
September BMP Q&A
By: Chuck Coup, BMP Forester (Ret.), Texas Forest Service
Q: I
have a question about a landowner that is clear-cutting a wetland / forest
swamp area. It is a patchy clearcut, and they are removing most of the
merchantable trees (the cypress and gum), leaving most of the tallow, gnarly
oaks, and willow. There are no issues with rutting because of the dry
conditions, and all best management practices (BMPs), to the best of my
knowledge, are being followed. Of course, it appears that the area is being over-harvested,
because I know the BMP handbook says you’re supposed to treat forest swamp
areas as if they were SMZs. The tricky part is that this is a land conversion
harvest. The landowner has managed the property for timber for many years, but
is conducting this harvest because he wants to turn the area into pastureland.
In fact, cows are already on the site. However, as I understand it, because
this is a land conversion harvest that is taking the property out of ongoing
forestry, BMPs would not apply. Is this correct?
A: An
excellent question! Let me start by saying great work consulting the BMP
handbook to find out about the guidelines for forest swamps. You are exactly right
that the green section of the handbook recommends treating these areas as if they
were SMZs; so clear-cutting would not be a recommended forest management
strategy. I am also glad to hear that the dry conditions allowed you to operate
in the wetland without causing ruts, because it is extremely important that the
natural flow patterns of these areas be maintained in order to protect the
wetland’s many beneficial functions.
Now, do BMPs apply to this wetland conversion harvest? Well
the answer is a little more complicated than a simple yes or no.
First, let’s start with some background information. As most
of you know, our forestry BMPs originate from the federal Clean Water Act (CWA)
which is directed at protecting our water resources. Section 404 of the CWA
specifically relates to wetlands and makes it unlawful to “discharge dredged or
fill material” (which includes rock, sand, soil, clay, and wood chips) into
“waters of the United States” (which includes wetlands such as forest swamps)
without a permit from the Army Corps of Engineers (ACOE); commonly referred to
as a 404 permit. This basically just means you can’t legally impact a wetland
without first obtaining a permit from the ACOE. Fortunately, forestry is
generally recognized as a land use that is compatible with wetland protection,
and as a result, the CWA specifically exempts forestry operations from requiring
404 permitting.
However, that permit exemption comes with a few important
conditions.
The first requires that the forestry operation qualify as
“normal silviculture,” which includes such activities as soil bedding, site
preparation, and harvesting. The second requires that the “fifteen mandatory
road BMPs” are followed (check your BMP handbook if you are not familiar with
these). The third requires that the operation must be conducted as part of an
“established” silviculture operation; which means that the area has previously
been managed for timber and the operation is just a continuation of that
management. The fourth requires that no toxic pollutants be discharged into the
waterway. And finally, the fifth requirement says that the purpose of the
operation cannot be to convert any part of a wetland (such as a forest swamp)
to a use that it was not previously subject to (such as pastureland). All five of
these conditions must be met in order to be exempted from the 404 permit
requirement.
Having gone through all of that, the answer to your question
is “No.” While still a good idea, BMPs do not apply to your wetland conversion
harvest, and therefore you are not required to harvest the area as if it were
an SMZ. However, this is not because wetland conversion operations are somehow exempt
from BMPs. Rather, it is because wetland conversion operations do not fall within
the forestry exemption, and therefore, are required by federal law to have a
section 404 permit from the ACOE.
For more information on wetlands and other BMPs visit the
Texas Forest Service webpage at http://txforestservice.tamu.edu/water or
contact me by phone at (936) 639-8180.
* This article was published in the September 2011 issue of the Texas Logger
Monday, August 1, 2011
August BMP Q&A
By: Chuck Coup, BMP Forester (Ret.), Texas Forest Service
Q: There
are all sorts of difficult situations that can arise when my guys are
attempting to construct a functioning wing ditch. Sometimes they work and
sometimes they don’t. Can you tell me some of the most common problems you come
across with wing ditches?
A: Isn’t
it amazing how a structure as simple as a wing ditch can sometimes be so
troublesome! The primary function of a wing ditch is to collect runoff water
from the road surface and roadside ditches and disperse it into stable areas
away from water bodies or other sensitive areas. They are typically most
effective when used in conjunction with a waterbar that intercepts, diverts,
and drains runoff water from the road surface and the roadside ditch on the
opposite side. It is really nothing more than a water outlet for the road, but
knowing where and how to construct them in certain situations can be very
tricky!
One of the most common problems I see with wing ditches is that
they are longer than necessary. It is generally not effective to construct a
wing ditch that carries runoff water long distances away from the road. This
practice unnecessarily exposes additional soil to erosion and increases the
distance that the runoff water has to flow before reaching stable, vegetated
ground cover. Long wing ditches also run the risk of discharging polluted water
into or near water bodies or other sensitive areas. Keep your wing ditches only
as long as necessary to encourage the water to flow away from the road. One
exception to this may be in extremely flat areas where it is difficult to get
the water to drain away from the road. Typically though, if you have a little
topography, gravity will do the trick. If you think you need to construct a
long wing ditch in order to deal with a large volume of water being carried
down your road, you should instead consider increasing the frequency of your
wing ditches (and waterbars) by putting them closer together. That will divide
the amount of water you are trying to manage between wing ditches.
Another problem I often come across is wing ditches that are
constructed as narrow channels using the corner of the skidder or dozer blade. I
frequently see these V-shaped channels in combination with wing ditches that
are too long, resulting in a turnout that erodes and carries sediments excessive
distances – completely the opposite of what we want. A better approach is to keep
the dozer or skidder blade level with the ground and make a wide flat outlet
that disperses the water over a broad area. This kind of outlet promotes sheet
flow versus channel flow which spreads the water out and reduces its speed.
Slow moving water cannot carry sediments as efficiently as fast moving
channelized water can.
Other problems are typically related to where the wing ditch
discharges. I occasionally come across waterbars that are correctly constructed
on the edge of an SMZ but have a wing ditch that carries the polluted water
through the SMZ and discharges it either directly into or within feet of the
stream channel. That’s bad news for the fish and other aquatic wildlife.
Another situation I repeatedly see are wing ditches constructed down steep
slopes which eventually leads to excessive erosion. One way that you might
avoid these situations is by putting a gentle uphill turn in your wing ditch
outlet. “J-hooking” your wing ditches, as it is called, can help to divert the
water away from sensitive areas like stream channels or steep slopes and also
helps to slow the water’s speed. However, don’t confuse this practice with the
futile attempt to carry water uphill by putting wing ditches on the high side
of the road or against the slope of the land. The wing ditch should still have
a slight down grade and follow the natural contour of the site (and be flat and
only as long as necessary). That’s one approach that I have found to be
effective, but I am sure that you guys have come up with more creative
solutions to these problems. If you have, drop me a line as I would love to
hear them!
Finally, if you get a chance, I would recommend that you go
back and take a look at some of the wing ditches you installed in the past,
especially the ones that you were uncertain about. See if they worked and if
they didn’t what you might need to do differently in the future.
For more information on wing ditches and other BMPs visit
the Texas Forest Service webpage at http://txforestservice.tamu.edu/water or
contact me by phone at (936) 639-8180.
* This article was published in the August 2011 issue of the Texas Logger
Friday, July 1, 2011
BMP Trivia Question
Access roads provide an effective and efficient transportation system to protect forest land and water quality when removing forest products from the harvest site, developing the forest for recreation, accessing the are for forest fire suppression, or other needed forest management activities. Properly located and constructed roads will provide safety, higher vehicle speeds, and longer operating periods while reducing operating and maintenance cost. According to the BMP Handbook, which of the following is the correct definition of a permanent road?A. A route over which logs are moved to a landing or road.
B. Primary or secondary roads constructed to provide all-or nearly all-season access for silvicultural activities and are maintained regularly.
C. A road constructed for a specific use or single operation and normally retired upon completion of the operation.
Click on "comments" below and post your answers.
Wednesday, June 1, 2011
June BMP Q&A
By: Chuck Coup, BMP Forester (Ret.), Texas Forest Service
Q: When dealing with temporary stream
crossings, I have been told several things about where to put waterbars to
prevent road sediment from entering the stream. I have heard that you are
supposed to put a waterbar on each side of the streambank at the crossing to
prevent any water flowing down the road from getting into the stream. I have
also been told to never put any waterbars inside the SMZ. Would you please
clear this up for me?
A: It
is certainly easy to see how both recommendations could seem valid, but let’s
see if we can’t shed some light on this debate.
The thought behind closing out a temporary stream crossing
by constructing a waterbar at the edge of a stream is that it will provide a
place to stop or redirect any water entering the SMZ just before it gets into
the stream. However, experience has shown that waterbars at the streamside
typically serve more as a source of sediment. These waterbars will often slough
off into the stream with a heavy rain. If rains are heavy enough to cause the
stream to overflow its banks, the waterbar may be completely washed away.
Therefore, as a general rule, waterbars should be kept at
least 50 feet away from the stream channel (i.e., outside the SMZ). A properly
constructed waterbar at the edge of the SMZ will divert water off the road as
it approaches the SMZ and give plenty of distance for the water to slow down,
spread out, and drop any sediment before it reaches the stream. Just be sure
you don’t construct a long narrow wing ditch off that water bar into the SMZ
that will channelize the water and direct it into the stream.
Of course, as with any rule, there are exceptions. If your
SMZ is wider than the minimum 50-foot recommendation then it would be alright
to have a waterbar within the SMZ. If you are dealing with steep approaches and
erosive soils then it may be necessary to construct an additional waterbar with
in the 50-foot buffer. However, you should try to keep it as far back from the
stream bank as possible and be sure that it does not discharge directly into
the stream channel.
It is important that you also re-establish the original
slope and condition of the streambank as best as you can when you pull out your
temporary stream crossing. An effort should be made to stabilize the
streambanks where the crossing and approaches to the crossing were. Stabilizing
these areas becomes even more important for crossings with more erodible soils
or steeper slopes. This can be accomplished using grass seed or logging slash;
however, you want to make sure that any logging slash you put next to the
stream is well incorporated into the soil and above flood level so that it will
not wash into the channel during high flows. If this is done, there should be
little or no erosion at the crossing.
As always, the very best way to prevent sediment from
entering a stream at a crossing is to avoid putting in the crossing in the
first place.
For more information on stream crossing BMPs visit the Texas
Forest Service webpage at http://txforestservice.tamu.edu/water or contact me
at (936) 639-8180.
* This article was published in the June 2011 issue of the Texas Logger
Sunday, May 1, 2011
May BMP Q&A
By: Chuck Coup, BMP Forester (Ret.), Texas Forest Service
Q: In recent months the outbreak of
wildfires and the threat of wildfires occurring has been high. I want to protect my timber from a possible
wildfire by installing firelanes around my tract. Are there any BMPs that I should follow
during this project to prevent any impacts on water quality from occurring?
A: Installing firelanes around your timber
is a great way to protect your investment by reducing the threat of a possible
wildfire. Firelanes work by creating a
barrier and removing the available fuel source between adjoining stands or
tracts. By removing the fuel source
along these barriers aids in preventing a wildfire one stand or tract to
another. However, it is important to
remember that there are potential impacts to water quality that can occur if
caution is not taken.
Guidelines for properly constructing and maintaining firelanes
can be found in the Texas Forest Service’s BMP Bluebook. These recommendations are designed to prevent
any unnecessary erosion form occurring thus minimizing the potential for
impacts on water quality.
Firelanes should be
constructed along the perimeter of the tract and follow the boundaries of
Streamside Management Zones. Locating these
barriers outside of SMZs will limit the amount of sedimentation that may
result. This will also protect the
litter and organic matter of the SMZ so it can continue to serve as a
filter.
To allow for proper
drainage and erosion control, waterbars and wing ditches should be installed in
a timely manner. Recommendations for
installing these devices can be found on pages 34 and 38 of the BMP Bluebook. These recommendations include how to properly
build waterbars, proper spacing for waterbars, and specifications on properly
installing wing ditches. When installing
wing ditches, make sure that the runoff water is not being discharged directly
into streams.
Regular maintenance on
firelanes is necessary to avoid potential erosion problems. This includes periodic inspections,
especially after heavy rains, to make sure that they are still functioning
properly and are not washed out. Mowing,
rather than blading, is the preferred type of maintenance because it minimizes
the amount of exposed mineral soil. Care
should be taken when blading is the only option.
Implementing these
control structures can be very costly when using heavy machinery. For economical as well as environmental
reasons, it is important to only build firelanes as wide and deep as
necessary. Woody debris and other
flammable material should be kept away from firelanes. These objects can ignite, creating a pathway
for the fire to spread into SMZs or adjoining lands. If you have a question regarding BMPs, please
call me at (936) 639-8180.
* This article was published in the May 2011 issue of the Texas Logger
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