November 2013 BMP Q&A

       By: Todd Thomas, Water Resources Forester, Texas A&M Forest Service

Q:  While conducting a complete harvest on a site with dense underbrush, my crew accidentally cut through an area that should have been reserved as an SMZ.  Now that what’s done is done, what do you recommend as our next move?

A: While I hate to hear of the destruction of an SMZ, do not worry, not all is lost.  First things first, in order to eliminate any confusion during site prep and planting, the area that would have been SMZ needs to be flagged off.  This will avoid any intrusion of site prep or other management activities down the road that could cause any damage to water quality.

Aerial view of Streamside Management Zones (SMZs) on a recent harvest in East Texas

During site preparation and planting it is extremely important that any equipment on site stay out of the newly flagged off SMZ to avoid soil disturbance next to the stream.  This will reduce erosion and the resulting sediment that could enter the stream.  Remember, since you have harvested the timber off the tract, there will be more water wanting to enter the stream since those trees are no longer there to use it.  This means that there will be more water in the soil, especially right next to the stream, making the area much more prone to rutting.  If you do decide to plant this area when you are planting the rest of the tract, be sure and plant it by hand so you don’t rut up this sensitive area. 

Going ahead and marking off the area that would have been SMZ will also be extremely beneficial if you plan on using herbicides during site prep.  This will eliminate the possibility of any herbicide being directly applied to the stream.  Also, not spraying here will allow vegetation to re-establish itself quickly, and reduce erosion potential.  Not to mention this helps with maintaining biodiversity for wildlife habitat, one of the side benefits of SMZs. 

It may not be a bad idea to go ahead and plant a mix of hardwood seedlings in this area, just to ensure that things begin to reestablish at a rapid pace.  However, there is a good chance that there is enough seed already in the soil for seedlings and shrubs to grow in this area pretty densely.  I have heard stories relating to similar scenarios where hardwoods were planted, but were eventually out-competed by seedlings that grew from the already existing seed bank.  How you choose to approach this is totally up to your discretion. 

If you plant anything, it is probably a good idea to at least put down some grass seed.  There is chart that is extremely helpful in determining what to plant on page 67 and 68 of your blue book.  This form of revegetation will hold the soil in place while any seedlings are getting established.  Remember, per Texas BMPs, that it is not recommended to use fertilizer within an SMZ (page 66, blue book).  This is because excessive nutrients entering the stream can greatly degrade water quality. 

In conclusion, while it is never a good thing to slick off an SMZ, there are measures to restore the SMZ and to correct the mistake.  Remember to delineate the area, keep out equipment, and to actively manage the area to reestablish vegetation so that it can return to a functioning SMZ.  Keep the questions coming; you can call them in to me at 936-639-8180, or email me at tthomas@tfs.tamu.edu.

*This article was published in the November 2013 edition of the Texas Logger

Texas Riparian & Stream Ecosystem Workshop – Carters Creek Watershed

 

 

 

November 21, 2013

College Station Wastewater Treatment Meeting Facility
2200 North Forest Parkway
College Station, Texas 77845 (map)

Trainings will focus on the nature and function of stream and riparian zones and the benefits and direct economic impacts from healthy riparian zones. The riparian education programs will cover an introduction to riparian principles, watershed processes, basic hydrology, erosion/deposition principles, and riparian vegetation, as well as potential causes of degradation and possible resulting impairment(s), and available local resources including technical assistance and tools that can be employed to prevent and/or resolve degradation.

These one-day trainings in watersheds across the state will include both indoor classroom presentations and outdoor stream walks.

The goal is for participants to better understand and relate to riparian and watershed processes, the benefits that healthy riparian areas provide, and the tools that can be employed to prevent and/or resolve degradation and improve water quality. At the conclusion of the training, participants will receive a certificate of completion.

Continuing Education Units Available

• Texas Department of Agriculture Pesticide Applicators License - 3 CEUs
• Texas Water Resources Institute - 1 CEU
• Texas Nutrient Management Planning Specialists - 6 hours
• Texas Forestry Association – up to 6 hours
• Society of American Foresters – up to 4. 5 hours
• Texas Board of Architectural Examiners “Acceptable for HSW credit”
• The program may also be used for CEUs for Professional Engineers.

Please complete the form below to RSVP for the Texas Riparian and Stream Ecosystem Workshop, November 21, 2013 at the College Station Wastewater Treatment Facility.

There will be a catered lunch available for $10 cash at the door, but please feel free to bring your own lunch as we will have a lunchtime presentation before heading to the stream site. Please go online and RSVP and select if you would like the catered lunch or if you will bring your own.

For more information or questions please contact Nikki Dictson at 979-458-5915 or             

n-dictson@tamu.edu

 

 

 

 

 

 

 

 

Cross Timbers Landowner Workshop

 Come join us for the Cross Timbers Landowner Workshop

 

Date & Time:
Friday, October 18th
8:30 am to 3:30 pm

Location:
White Rock Ranch
2205 Clark Lake Road
Weatherford, TX 76088

Come learn about:

• The Cross Timbers region 
• Wildlife Habitat Management
• Range Management
• Conservation Easements
• Tax Appraisals
• Understanding Tree Valuations

Don't miss our guest speaker  - Texas State Representative King's presentation on Eminent Domain

 
Admission is $10 and lunch is provided

RSVP by October 15th to

Renee Burks, Staff Forester
Texas A&M Forest Service

rburks@tfs.tamu.edu

254-386-3361

September 2013 BMP Q&A

           By: Todd Thomas, Water Resources Forester, Texas A&M Forest Service

Q: My crew is in the middle of thinning a 15 year old pine plantation.  In the middle of the tract, leading down to an intermittent stream is an old legacy road that has washed out over time.  It is very apparent that the when all the timber was harvested over 15 years ago that no BMPs were used.  As this gully approaches the stream it gets deeper and deeper.  Where the gully meets the stream it is deep enough to swallow a pickup!  For the most part, the gully hasn’t eroded any more in quite some time.  There is little to no evidence of recent soil movement, and there is a pretty heavy layer of pine straw and other litter on top of the soil.  We have kept all our equipment out of the gully and haven’t cut any trees on the edge of the gully in order to keep things from washing out anymore than they already are.  What is our next move here?  How should we treat this highly eroded legacy road in future management operations? 

A: Excellent question, and one that addresses an issue that I am sure other folks are experiencing out there.  First and foremost, good job staying out of the gully and not harvesting the trees along the edge.  Even though the gully started out as a poorly placed road, it is now acting as an ephemeral drain and should be treated as such. 

The best way to keep this gully from eroding further is to keep equipment out entirely and to maintain a buffer of trees around the edge and above the head of the gully.  Now you may remember that Texas Forestry BMP guidelines do not require an SMZ on ephemeral drains, but depending on the situation, some protection is needed.  This is certainly a situation where some protection is needed.  The amount of protection, the width of the buffer, will depend on the soil type and topography of the site, based on your professional judgment. 

The buffer will accomplish several goals in the name of erosion prevention and protecting water quality.  The first goal is interception.  The canopy of the trees comprising the buffer will intercept rainfall and reduce the resulting soil movement from raindrop impact.  The second is root structure.  The roots of these trees will hold the soil in place, reducing the chance of the gully getting wider.  Since you are in the process of harvesting timber on site, the amount of water traveling to the gully is going to increase.  This surplus of water is a result of the harvested trees not being there to use it anymore.  The trees making up the buffer will intercept the bulk of this water, preventing further erosion. 

Maintaining a buffer also limits equipment intrusion.  Remember, since water is naturally draining towards the gully and in more abundance with less timber around to utilize it, the area around the gully is going to be much more prone to rutting.  Even in dry conditions it is important to minimize equipment operations immediately adjacent to the gully as this can cause soil disturbance that will eventually lead to further erosion issues. 

While it may seem like a good idea to place hay bales, slash, or silt fences in the gully, this should be avoided.  In a case such as this, where everything seems to have stabilized relatively well, putting something in the gully would likely cause further erosion on the side banks causing the gully to widen.  Placing hay bales or silt fences in the gully would not only enhance erosion, but also costs time and money.  Time and money that you could be devoting to other aspects of your operation, such as installing BMPs elsewhere!

In conclusion, an ephemeral drain is an ephemeral drain no matter how it started out.  No matter if a drain was put here by Mother Nature or the faults of man, at this point it deserves our protection.  Keep the questions coming, you can send them to me at tthomas@tfs.tamu.edu or call them in using the phone number 936-639-8180.  

*This article was published in the September 2013 edition of the Texas Logger

August 2013 BMP Q&A

                By: Todd Thomas, Water Resources Forester, Texas A&M Forest Service

Mmmmm....dips. But not quite.

Q: While looking through the blue book, I noticed that you have specifications for both broad-based dips and rolling dips.  I was always under the impression that these were basically the same thing.  Can you explain the difference between the two, and when you might use one instead of the other?

A: Excellent question, and one that we get quite a bit!  Upon first glance, rolling dips and broad-based dips do not appear to be much different at all.  They both accomplish the same goal: to provide cross drainage on in-sloped roads.  The differences between the two are quite subtle, but knowing these differences can save you time and money down the road when it comes to road construction and maintenance. 

Both rolling dips and broad-based dips are reverse slopes in the road surface that outslopes for natural cross-drainage.  Rolling dips are designed to be used on haul roads and heavily used skid trails.  Broad-based dips differ in that they are designed for use mostly on heavily used haul roads.  Rolling dips can be used on roads with up to a 15% grade, while broad-based dips should be used on roads that do not exceed a 12% grade.  The spacing on broad-based dips should change with every 2% change in gradient, while the spacing with rolling dips changes with every 5% change in gradient. 

With broad-based dips, the reverse grade should always be 3% and approximately 20 feet in length.  Rolling dips are slightly more flexible in their size and gradient.  Guidelines for rolling dips call for the reverse grade to be between 3% and 8% with the length ranging from 10 to 15 feet.  The slight differences between the two allow for higher vehicle speeds on broad-based dips than on rolling dips. 

Since broad-based dips are used on high traffic roads, some other considerations may be necessary.  On some soils, the dip and reverse grade section may require bedding with crushed stone to avoid rutting the road surface.  Also, energy absorbers such as rip rap, and in some cases, a level area should be installed at the outfall of the dip in order to slow down runoff and keep erosion minimized. 

With both types of dips, neither the dip nor the hump should have a sharp, angular break, but instead should be rounded to allow smooth flow of traffic.  Properly constructed dips require minimal maintenance and continue to function years after abandonment, saving your road and saving you money. 

Please keep your questions coming.  You can email them to me at tthomas@tfs.tamu.edu or phone them in by calling (936)639-8180. 

*This article was published in the August 2013 edition of the Texas Logger

June 2013 BMP Q&A

By: Todd Thomas, Water Resources Forester, Texas A&M Forest Service

Q: When harvesting trees within an SMZ I've always been told to keep tops and slash out of the stream, however, when you walk along a stream in the forest there are tons of limbs already in the stream. What is the big deal?  I know it is a guideline, but why is it so important to keep limbs out of the stream when there are already so many there naturally?

A: You bring up a good point, but since there are in fact lots of limbs and debris in the stream bed, there is no need to add any additional debris.  First and foremost, the more debris that gets added to a stream the greater the likelihood of the stream being dammed up and as a result causing flooding.  Flooding is going to happen from time to time with heavy rains, but the less floods in these forested streams the better.  With excessive flooding comes the potential for more erosion on a site, as well as the potential for nutrient loss in the soil.  As the flood waters recede, the eroded soil and nutrients are then carried to the stream, severely affecting water quality.  This flooding could also cause a reduction in the amount of water downstream, further affecting other bodies of water.

Build up of slash in an intermittent stream in East Texas

With the increase of limbs in the stream also comes more scouring or erosion of the stream bank itself.  Since this already occurs naturally, additional scouring can be problematic.  The first issue comes with more sediment in the stream.  More sediment traveling downstream has many negative effects on water quality as well as on aquatic plants and animals.   This increased scouring also releases nutrients that were once stored up in the soil of the stream banks.  As more nutrients travel downstream, they can accumulate and degrade water quality. 

Another benefit of keeping the slash out of the stream is being able to utilize the slash elsewhere on the tract.  Slash is an excellent tool for erosion prevention on closed out skid trails and temporary roads.  Why contribute to a problem when something can contribute to a solution? 

In conclusion, keep slash out of streams, the folks downstream will thank you, aquatic life will thank you, and the landowner will thank you.  Remember extra debris in the stream contributes to flooding and water quality degradation.  Remember to keep the questions coming, you can send them to me at tthomas@tfs.tamu.edu or just phone it in by calling (936) 639-8180.  

*This article was published in the June 2013 edition of the Texas Logger  

May 2013 BMP Q&A

By: Todd Thomas, Water Resources Forester, Texas A&M Forest Service

Q:  One type of temporary stream crossing that I have heard mentioned, but never seen or even heard discussed in great detail are PVC bundles.  What exactly are these and how can I construct my own?

A:  Excellent question about an innovative stream crossing method.  PVC bundle crossings can be constructed relatively cheap from readily available materials and can be re-used and repaired without issue.  While not suited for large streams, PVC bundles can be used on most ephemeral and intermittent streams with a U-shaped profile that are not more than 10-feet wide and 4-feet deep in channels with low flow.  Think of these bundles as a large handful of straws. 

In order to create a 12-foot wide pipe bundle that is 16-feet long when laid flat, you will need 12 20-foot joints of 4-inch diameter schedule 40 PVC pipe, four 18-foot lengths of 3/16 inch galvanized steel cable, and eight 3/16 inch cable clamps.  The 20-foot joints of pipe should be sawed into 12-foot sections with the remaining eight feet sawed in half so there are two 4-foot joints, per 20-foot joint of pipe.  Next, drill ¼ inch holes completely through the 12-foot long joints at locations 2-feet and four-feet from either end; on the 4-foot long joints, 2 ¼-inch holes should be drilled, each 1-foot from the end.  Alternate one 12 foot long joint with one row made of two 4-foot wide joints placed 2-feet from each other.  Finally, you will connect the joints of pipe.  To do this, string each strand of galvanized cable through the holes in each joint of pipe.  Once strung through, make loops on the ends of each cable and secure them with the cable clamps.  Each cabled section should be loose so pipes can conform to the stream channel.  When you are done there should be 2 4-foot sections of PVC remaining, these can be used at your discretion.   

In order to utilize your newly constructed bundle, begin by lying on end of the pipe bundle at the top of the bank and allow the rest of the bundle to lie in the stream channel slowly piling it back on top of itself.  The ends of the bundle should be resting on banks opposite each other.  The loops in the cable can then be used to tie off the bundle to anchor points on each side of the stream.  You may want to lay boards across the bundle perpendicular to allow for better traction when crossing.  When it is time to remove the crossing, simply undo the anchor points and lift the bundle out by the cables that are attached the pipe on top.  After the bundle is removed be sure to inspect it for any damage and replace any damaged pipes before re-use. 

Once the bundle has been removed, always remember to stabilize your approaches, just as you would with any stream crossing.  Also, keep in mind where appropriate stream crossings should be located: straight sections of stream that can be approached at a 90-degree angle.  This concludes this month’s BMP Q&A, remember you can send any questions to me at tthomas@tfs.tamu.edu, or you can phone them in by calling (936) 639-8180. 

*This article was published in the May 2013 edition of the Texas Logger

What to consider: Culverts

Poorly installed and improperly designed culverts can lead to excessive erosion, damage to streams, high maintenance costs, and road failure.  In order to prevent these issues it is important to consider culvert type, diameter, length, and location.

Excessive sedimentation from a poorly planned culvert

Type
There are two types of culverts: stream crossings and cross drains.  The first type, a stream crossing culvert, is generally placed in a location where a permanent stream crossing may be necessary, since it is often too costly both economically and ecologically to remove. These culverts allow both stream flow and aquatic wildlife to pass underneath the road.  The second type, cross drains, are used to transport upland runoff, accumulated in road ditches on the upland side of the roadway to the lower end where both flow volume and velocity can be dissipated.

Mouth of a cross drain culvert

Diameter
Culvert diameter is determined by both the soil type on the site, how steep the site is, and the acreage of the watershed that the culvert drains.  Taking into consideration these factors ensures that the culvert is sizable enough to handle the maximum volume of water that it may encounter.

Culvert size chart from page 51 of the Texas Forestry Best Management Practices Handbook 

Length
Culvert length is dictated by how wide the road is.  Culverts should be long enough so that each end extends at least one foot beyond the edge of the fill on either side.

Location
Culvert location is paramount in dictating the longevity of the culvert.  In stream crossings, culverts should be placed in a section of stream where the channel is straight and the stream bed is firm.  Cross drain culverts should be spaced out depending on slope.  Cross drain culvert spacing can be determined using the following formula:

Culvert spacing = (400'/slope%)+100
         *Slope in percent is expressed as a whole number (i.e. 15%=15)
               
            Example: Spacing = (400'/15)+100'
                          Spacing= 127'

Conditions
In addition to factoring in culvert specifications, it is also extremely important to factor in current weather conditions and trends.  Culvert installation should be done when stream flows and chance of rain are low.  Ideally, the entire installation process should be completed before a rain event.

UP NEXT:  Installing your culvert

2013 Texas Wildlife and Woodland Expo

On Saturday thousands of visitors descended on the Lone Star College-Montgomery Campus in Conroe to learn about the forests of the region in which they live and how to best take care of it through hands on clinics, information booths, live demonstrations, and children's activities.  Attendees ranged from urban homeowners to rural landowners, boy scouts, girl scouts, outdoor enthusiasts and everyone in between.

Donna Work explains the importance of streamside management zones using the SMZ simulator

Hughes Simpson discusses benthic samples with visitors

The Water Resources program was on hand to answer questions related to water resources and provide information on forestry BMPs.  Donna Work, Hughes Simpson, and Todd Thomas handed out information and discussed BMPs and the forest-water relationship to any interested patrons of the event.  A demonstration was on hand to illustrate the importance of maintaining Streamside Management Zones (SMZs) complete with rainfall and runoff simulation.

Todd Thomas talks BMPs with expo enthusiasts 

SFA Students Experience BMPs Firsthand

Last week, 46 students enrolled in ecology at Stephen F. Austin State University were able to view various Texas forestry best management practices (BMPs) implemented on the ground in northeast Nacogdoches County.  In addition to viewing methods of erosion control in forestry operations, the students learned about various facets of the program including the effectiveness monitoring project.  While learning about the BMP effectiveness project, the students were able to view equipment used to sample benthic organisms, as well as some organisms that were living in the creek running through the tract.

Biologist Donna Work discusses benthic macroinvertebrates 

March 2013 BMP Q&A

By: Todd Thomas, Water Resources Forester, Texas A&M Forest Service

Q:  I was looking at a Texas BMP compliance monitoring checklist and in the comments section, it mentioned “below grade roads”.  I have heard this term mentioned before, but I have never been quite sure what a below grade road is and what exactly can I do about them?

A: I am glad you asked this.  A road that is below grade is one that is lower than the surrounding land.  Many of the roads in East Texas are very old and can be classified as below grade. 

Below grade roads usually occur after years of being worked and graded without any new material brought in to build them up, or from just being worked from one direction, to the point that the road essentially becomes a channel for runoff water.  As you may remember, with BMPs we are trying to keep from channelizing any runoff.  When runoff is channeled it begins to accelerate, especially in areas with a great deal of topography.  This accelerated runoff will increase erosion and the amount of sediment that reaches our streams. 

The issue of below grade roads is not limited to areas with rolling terrain or steep topography, below grade roads can create significant problems in flatwoods as well.  The issue isn’t so much a concern with water quality, but with access.  Water will always flow to the lowest spot on a site, and if this happens to be the roadway, then the water will not properly drain.  The road will then become saturated, and stay wet for most of the year.  Wet roads can lead to poor access, and cause severe rutting if traveled. 

These situations can develop gradually over time if roads are not properly constructed or may occur when subjected to heavy rains.  The formation of these areas can also result from trying to access a wet road by cutting it down until a dry surface is reached.  While this might be a temporary solution to an access problem, it can lead to erosion problems. 

To fix or reduce the severity of these problems, the first thing you need to decide is if the road in question will function as a temporary or permanent road.  This can be dictated by the amount of traffic your road will handle in the near future.  High traffic zones will generally be more expensive to control than low traffic zones.   If the road is not necessary then it should be closed.  In order for the road to stay in use the surface will need to be built up and water control structures will need to be put into place.  The type of structure will be dictated by the traffic type.  

There are several effective ways to reduce the impact to water quality on below grade roads.  It is best to make sure that the roadway is well drained when dealing with permanent systems located on steep topography.  Installing waterbars with good outlets for the water is recommended.  Instead of using the dirt in the roadway to build these structures, try incorporating some of the bank dirt.  This will allow you to construct a waterbar and at the same time make it easier to divert the water. 

When dealing with temporary roads, revegetating is a great option to hold the soil in place and minimize the amount of erosion and sedimentation that may occur.  A more cost efficient way to hold temporary roads in place is to distribute fine slash on the roadbed.  If you have any questions about BMPs, please do not hesitate to contact me at (936) 639-8180 or email me at tthomas@tfs.tamu.edu.  

*This article was published in the March 2013 edition of the Texas Logger

February 2013, BMP Q&A

By: Todd Thomas, Water Resources Forester, Texas A&M Forest Service

Q: In the quiz last month you asked a question where we would need to know the slope in order to have appropriately spaced windrows.  My question is how are we supposed to know the slope in the field off hand without a tool such as a clinometer? 

A: I am glad you asked this question and I am always glad to highlight areas of the blue book.  However this time I will not be referencing the text of the book, but a feature that many of you may have noticed, but never paid much attention to.  This feature is the slope calculator. 

The slope calculator can be found on the inside of the back cover of the blue book.  There are instructions on how to use it, but since you asked, I will go ahead and explain.  In addition to your blue book, you will need a piece of string, approximately 12-inches long and something to use as a weight, such as a small nut or washer.  First, tie one end of the string to the middle ring of the spiral binding or punch a hole through the cover of the book at the apex of the slope calculator.  Go ahead, it is okay.  There is a small circle there for your reference.  Next, tie your small weight to the loose end of the string. 

Now that your slope calculator has been constructed, here is how you will use it.  The spiral binding should be on top, use this as your sight.  With the binding parallel to the ground, sight the book up or down the slope (depending on which way you are facing), the string will hang vertically and the slope can be read directly along the line where the string lies.  The number on the line with the string is your percent slope.

Now that you are aware of the slope calculator, there are no excuses for not having your blue book with you.  Not only is the book full of BMP information, it is also a tool that you can use in your day to day functions.  In addition to windrow spacing, this tool can be used for determining road gradients so you know where to locate your water control structures such as waterbars, wing ditches, culverts, and dips; in conjunction with the culvert size chart to determine culvert sizing; as well as how wide to make SMZs when near steep slopes, or any other time you need to know the percent slope in a pinch. 

In conclusion, keep those blue books handy, you never know when one might come into use.  If you need a blue book you can get one from your nearest TFS office.  Please keep your questions coming.  You can email them to me at tthomas@tfs.tamu.edu or phone them in by calling (936)639-8180.  

*This article was published in the February 2013 issue of the Texas Logger