Texas Forestry BMPs - Constructing Waterbars and Wing Ditches

Texas Forestry BMPs - Locating Waterbars

Outfall Protection

What exactly is outfall protection?  Outfall protection is an essential element of proper culvert installation and can certainly extend the life of your culvert.  Outfall protection most often consists of rip rap or other large aggregate placed at the end of the culvert to intercept and absorb the energy produced by the water exiting the culvert. 

Rock Outfall Protection

As water flows down a ditch or stream, it is gaining speed or velocity.  This velocity increases once the flow of water is concentrated in a culvert.   Culverts also tend to have more smooth edges, or less roughness than the ditch or streambed to slow this water down.  Once this water exits the culvert, it is moving relatively fast with lots of power ready to move some soil and cause erosion.  In addition to scouring out the channel down from the culvert, this water tends to swirl around as it leaves the culvert and can eventually wash out the culvert, costing you money to come in and re-install your culvert. 

Outfall protection intercepts this flow and spreads it out, thus reducing the speed of the water and its erosive power.  Outfall protection can be as simple as some old bricks, busted up concrete, old tires, or large rock.  On cross-drain culverts, where you are transferring runoff from across the road, you may want to not only put outfall protection under the end of the culvert, but also on the bank adjacent to the culvert exit, to help preserve the bank and prevent excessive erosion.   On culverts used for creek crossings it is often important to not only have outfall protection on the culvert exit, but also on the sides of the banks on either side of the culvert exit.  This will prevent swirling water exiting the culvert from eroding the stream banks and eventually blowing out the sides of your culvert. 

Outfall protection can also be an important component of wing ditches on some of your woods roads that are generally only used during forest operations.  In these instances, you may not need to invest in large, rock aggregate, but instead can prevent excessive erosion by placing slash or brush at the outlet of the wing ditch.  Another method of providing outfall protection on wing ditches could be using vegetation.  If this is an area that doesn't receive a large amount of runoff, it is a good idea to use our seeding chart on page 67 of the blue book. 

In conclusion, outfall protection is essential in protecting your culvert, ditch, stream, wallet, and water quality in general.  Outfall protection will save you money by not having to re-install culverts and reduce the frequency that you have to come and pull your ditches.  Outfall protection protects streams health and preserves water quality by reducing the amount of sediment traveling downstream that result from stream bed and stream bank scour.  

May 2014 BMP Q&A

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

Q: As a result of some of these spring time rains we have been experiencing, several of the permanent roads we use have stayed wet and become a major headache.  For future reference, what do you recommend to help decrease the amount of time it takes to dry these roads out?

A: After some of the dry weather we’ve had the last couple of years, there’s no doubt that the rain is welcome, but with it comes issues like the one you’ve brought up.  As they say, “the wetter the road, the weaker the road.”  One method that comes to mind for decreasing the amount of time it takes for a road to dry out is called “daylighting.”

Sun and wind are the primary agents needed to dry out a road.  Daylighting is a method that that entails clearing trees along the edge of the road in order to increase air circulation and allow more sunlight to hit the road surface.  The forest canopy intercepts quite a bit of wind and sunlight.  The more sun and wind that reach the road, the faster it will dry out, allowing you to work more efficiently, reducing erosion potential, and increasing the life span of your road.  How far you decide to remove these trees on the sides is up to your discretion, really just enough to get that sunlight and wind onto the road surface.  

 

This road is receiving optimum sunlight and air circulation now,
but later on these trees along the side may need to be removed.

Due to our location on the Earth’s surface, the southern side of east-west running roads should receive the most attention in order to maximize the amount of afternoon sun that hits the road.  Generally speaking, afternoon sun has a greater intensity than morning sun and a southern exposure will receive more direct sunlight than a northern exposure.  On a north-south running road, the west side should have more trees removed than the east side, to maximize the afternoon sun.  In areas with substantial curves in the road, go ahead and take several trees out of the inside of the curve to enhance the daylighting process and to increase visibility down the road as a safety precaution. 

In addition to allowing the road to dry faster, daylighting also helps to increase vegetative cover.  Increased grasses on the road surface when the road is not under heavy traffic loads will do two things.  The root structure of the grasses will do an excellent job of holding soil in place while the grasses themselves intercept rainfall and reduce soil particle displacement from raindrop impact.  The second benefit to the road is that the grasses will also aid in removing moisture.  As these grasses grow and conduct photosynthesis, they will remove moisture from the soil comprising the road bed and then transpire it into the atmosphere.  The increased number of grasses and forbs growing in the road and on the sides of the road will be of great benefit to wildlife as a food source.  So you are not only helping the road system but you are helping to feed our furry friends.  Who knows, maybe they’ll grow some bigger antlers and be more convenient to load into the back of the pickup since they are hanging out on the road! 

In conclusion, if your primary access roads are staying too wet, you may want to consider removing some trees along the side of the road in a process known as “daylighting.”  Remember, forest roads have the potential to severely degrade water quality and by keeping them in good shape, you are helping to keep our waters clean as well.  If you have any questions, feel free to call me at 936-639-8180, you can reach me by email at tthomas@tfs.tamu.edu, or just swing by our office in Lufkin. 

*This article was published in the May 2014 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

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

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

December 2012 BMP Q&A

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

Q: Awhile back I noticed on some closed out skid trails that had been revegetated, not only was rye grass used, but they had also used some clover in the mix.  Is there any benefit to planting clover when in areas that you are revegetating?

Revegetated Logging Road, East Texas

A: I am always glad to hear about revegetation, as it is an excellent method of preventing erosion on roads and other disturbed areas.  It is even better to hear of the clover being used in the mix.  This is because clover is a type of plant that is also known as a “legume”.  Legumes can be important in areas where there has been a considerable amount of soil disturbance such as a skid trail or approach to a stream crossing. 

Legumes perform what is called nitrogen fixation.  In other words, they take nitrogen from the air and put it back into the soil.  Nitrogen is an extremely important nutrient for plant growth.  This is why sometimes in agricultural operations you will see peanuts or soybeans used in crop rotation, since they can contribute nitrogen back to the soil that was depleted by the previous crop.  In an area with a great deal of disturbance it is important to incorporate something in your revegetation that can contribute back to the soil not only by helping to hold it in place, but by delivering a much needed nutrient that will help other grasses to grow, further preventing erosion. 

Subterranean clover

On page 66 of the blue book, it says that “legumes should be used in mixes with grasses.”  On the next page it gives some options for different legumes to use.  The legumes that we recommend incorporating are Singletary peas, Hairy vetch, Arrowleaf clover, and Subterranean clover.  However, if you choose to incorporate another legume, that is great also.  In general, all clovers, as well as plants that have some sort of seed pod (such as peas or beans) are legumes. 

A side benefit of planting legumes is that they are a great food source for wildlife.  Most legumes are high in protein, and all our deer hunters out there know that additional protein can increase antler growth in whitetail deer.  I’m sure the landowner will be extra happy knowing that you have helped their quest for “Muy Grande”.  This is just a side benefit while you are doing an excellent job at rebuilding soil productivity and reducing erosion. 

So remember to always include legumes in your revegetation and to keep the questions coming.  You can email me your questions at tthomas@tfs.tamu.edu or by phone at (936)639-8180.  Also, be sure to pay a visit to our blog at http://tfswater.blogspot.com.  On the blog you can find old Q&A articles, as well as additional information on how to best keep our waters clean while providing the world with forest products.  

*This article was published in the December 2012 issue of the Texas Logger

The basics of waterbars and wing ditches

The primary pollutant that enters our waterways from forestry operations is sediment.  This sediment comes mostly from roads, skid trails, and firebreaks.  Sediment is carried from overland flow that has gained enough velocity to detach soil particles and carry them with it; this overland flow, if not slowed down and dispersed, ends up in the stream, sediment and all.  One method of slowing down overland flow, as well as dispersing any sediment that it is carrying with it is to construct waterbars in trails, roads, and firebreaks.

Waterbars should be constructed at a 30-45 degree angle, turning overland flow out and away from the road.  

Accompanying a waterbar should be some sort of a turnout, more commonly referred to as a "wing ditch."  As the overland flow is intercepted by the waterbar, it is diverted into the wing ditch and dispersed before it has the opportunity to gain speed and cause further erosion.  It is also important to note that wing ditches should be constructed to be more flat than v-shaped.  This encourages diverted flow to dissipate rather than be concentrated.  

When constructing waterbars it is important to be sure that both ends are tied in to the edge of the road.  This prevents "blow outs" or water from going around the waterbar.  

Waterbars should never be constructed perpendicular to the road, this forms a dam, causing water to stand in the road.  Even though any overland flow has been put to a stop, the integrity of the road has been compromised, due to the 90 degree waterbar with no turnout accompanying it.  

Waterbars and wing ditches should never discharge into streams.  This increases stream bank erosion as well as increases the amount of sediment that enters the stream as a result of operations.

BMP Fact Sheets

Need Some Quick Info on Forestry Best Management Practices?


Texas Forest Service has several fact sheets available to help you understand various aspects of using Best Managment Practices during your forest operations. These are a great resources for landowners or land managers unfamiliar with forestry BMPs.

Topics include:

• BMP Guidelines Overview
• Forest Roads
• Reasonable BMP Expectations
• BMPs for Reforestation and Site Preparation
• Stream Crossings
• Streamside Management Zones 

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

November BMP Q&A

By: Chuck Coup, BMP Forester (Ret.), Texas Forest Service

Q:   The Blue Book mentions rutting on roads but not so much about rutting in the harvest area. Are there BMP guidelines for rutting that apply across the harvest area as well? What are the concerns for rutting in the harvest area and how would you evaluate a site if you were conducting a voluntary site evaluation?

A:   Great question, and one that could really use some clarification, especially as we move into the wet season!

Rutting is one of those situations where everybody loses. A skidder slogging through the mud certainly does not increase the efficiency of a logger’s operation, and landowners know that extensive rutting can lead to erosion and soil compaction, which can have a substantial impact on future tree growth. Rutting can also lead to environmental and water quality issues, especially if it occurs on steep slopes. 

Rutting generally results from the tires of vehicles such as skidders, log trucks, pickups, ATVs, etc., operating under wet conditions. Most of the rutting occurring in the harvest area (i.e., off the established roads) will be caused by skidder traffic and to a lesser degree the shear. The BMP guidelines do not specifically mention the shear, but it would be considered part of the skidding operation since it travels over essentially the same area.

So, are there guidelines that cover rutting in the harvest area? I think that question can be answered by mentioning one point; skidding operations occur on skid trails. Skid trails are defined as a route over which logs are moved to a landing or road. So if a skidder passes over an area, any rutting that it causes would be considered occurring on a skid trail, and therefore be addressed by BMPs for skid trails. Make sense?

Rutting on skid trails is covered under the recommended specifications for skid trails in Part II of the Blue Book. The guidelines recommend that when soils are saturated, skidding should be restricted to prevent excessive soil compaction and channelized erosion. The general rule of thumb for determining excessive rutting is no deeper than six inches for no more than 50 feet (or about two skidder lengths). That comes from number 18 under the recommended specifications for haul roads in your BMP Blue Book.  Certainly there are things you can do to minimize rutting during your operation.  Using high flotation tires, keeping skidder loads light, or shovel logging extremely wet sites are all possible options.

But, don’t get the impression that when we do a site evaluation we come with ruler and tape measure in hand ready to measure every rut we see. Remember that BMP guidelines are for reducing impacts to water quality. When determining if rutting is too extensive, there are several factors to consider. Look to see if the ruts will change the direction of water flow, or cause it to puddle the next time it rains. Soil type and slope are both very important factors to consider. Look to see if the ruts will in some way channel rainwater so that it may deliver sediment to a stream. If you notice these things happening, then it may be time to head to drier ground. Our evaluations take the entire site into consideration, so if it is obvious to us that you pulled off when you noticed rutting started to occur, our evaluation will certainly reflect that.

For more information on BMPs visit the Texas Forest Service webpage at http://txforestservice.tamu.edu/water, contact me at (936) 639-8180.

* This article was published in the November 2010 issue of the Texas Logger

September BMP Q&A

By: Chris Duncan, BMP Forester (Ret.), Texas Forest Service

Q:   I ‘m getting ready to move onto a fairly large tract for a timber harvest.  This particular tract doesn’t have much in the way of an established road system, so I will be constructing most of the roads for the harvest.  The landowner wants me to make part of the road system a permanent road which he will be able to use for access to his tract in the future.  I anticipate that I will need to have at least 1 and maybe 2 material borrow sites to complete this permanent road as the landowner has requested.  What I would like to know if there any guidelines for road material sites that pertain to best management practices?

A:   This is a very good question.  We have written several articles in the past about road BMPs, but have not mentioned a whole lot about what should be done if there is a need to “borrow” materials from the site.  Deposits of surfacing, fill, and site stabilization materials located on the tract are an extremely important resource for forest management activities.  Excavation of these deposits represents a potential for nonpoint source pollution.  Proper planning, layout, maintenance, and reclamation are critical to ensure maximum utilization of materials while minimizing soil movement and impacts to water quality.

Carefully assess the tracts natural drainage patterns, soil types, slopes, and any adjacent streamside management zones (SMZ) to determine the best location, size, and shape of the needed material site.  Deposits covering large areas should be divided and worked in stages, maintaining a minimum size working area and accomplishing partial or complete reclamation of the disturbed area before moving on.  Avoid leaving large areas disturbed for extended periods, active or not.  Road material sites should not be located within an SMZ.  They should be located a minimum of 50 feet from the SMZ edge, but if they must be closer than 50 feet make sure to plan for control measures that will protect water quality.

While material sites are active; use settling basins, waterbars and/or terraces to slow runoff and disperse surface flow.  When extended periods of inactivity are expected, use temporary erosion control measures such as silt fences or straw bales to control surface runoff.  When possible, do site work during dry weather to eliminate excessive runoff and accelerated erosion of freshly disturbed areas.

Upon completion of pit operations and depletion of the deposit; redeposit and shape the overburden in a uniform layer over the pit area.  Make sure the pit has adequate drainage to prevent soil movement and stream sedimentation.  Finally, reclaim the site to aid the future use of the area and implement control measures to minimize surface runoff for each case.  Consider the area's slope, soil erosiveness, and capability to naturally revegetate and then fertilize and reseed all disturbed areas as needed.

For more information on forest road material site BMPs and other BMPs visit the Texas Forest Service webpage at http://texasforestservice.tamu.edu/water, contact me at (903) 297-3910.

* This article was published in the September 2010 issue of the Texas Logger

December BMP Q&A

By: Chris Duncan, BMP Forester (Ret.), Texas Forest Service

Q:   I was signed up for the BMP Forest Roads workshop in Jefferson back in October, but it was cancelled.  I was wondering if you have any information about BMPs for forest roads.

A:   First off, I’m sorry we had to cancel the BMP Forest Roads workshop in Jefferson.  We did not get enough people to sign up for that course.  We may try to schedule another workshop next spring or summer, but we need your support to make these workshops in NE Texas work. Secondly, in the August issue I wrote about several tools which should be used when available to help aid you in the planning process.  Most of these tools are available at little or no cost to you.  In the September issue, I listed several factors to consider when planning your forest road layout.  Last month I addressed the construction phase for new forest roads. This month I will be wrapping up the forest roads article series with a few pointers on road maintenance/repair.

Proper maintenance/repair of permanent forest road access systems is vitally important to all logging and land management activities.  Road systems should be kept in serviceable/usable condition to minimize erosion by controlling rainfall runoff.  Keeping road systems in serviceable/usable condition has several benefits including decreasing down time caused by impassable roads and reducing impacts to water quality.

When possible, restrict traffic on roads during wet weather conditions.  If roads must be used in wet conditions, consider using materials such as wooden mats, gravel, and geo-textile fabrics to protect the road surface from damage.  Haul only during dry weather in normally wet areas, erodible soils, or on roads with a gradient of more than 10%.  Close or restrict traffic flow following maintenance/repair activities on sensitive permanent or temporary roads to allow them time to stabilize, re-vegetate, and heal over before using again.

Inspect road systems at regular intervals to detect and correct any maintenance/repair issues.  Check to make sure that road surfaces are crowned or outsloped to dissipate surface runoff.  Ensure that all ditches and culverts are free from siltation, logging debris, brush, and other obstructions to allow unrestricted passage of water.  Keep road surfaces free of obstructions, ruts, and logging debris which may restrict water flow from the road surface.  Re-work road surfaces to remove ruts when the average rut depth exceeds 6 inches over a distance of more than 50 feet, or when erosion damage may occur from hauling operations.  Care should be taken to avoid creating a “below grade” road when re-working the road surface.

When all forestry activities have been completed re-work the road surface if necessary. Ensure all drainage systems are open, and seed all areas of bare soil on and along the road system which are subject to excessive erosion.  Close or retire any roads which are not currently in use, and periodically inspect them to ensure their integrity.

These are just a few of the guidelines that should be considered while maintaining/repairing forest road systems.  I encourage you to attend one of our upcoming BMP Forest Roads Logger Training Workshops for more information.

For more information on forest road BMPs and other BMPs visit the Texas Forest Service webpage at http://texasforestservice.tamu.edu/water, contact me at (903) 297-3910.

* This article was published in the December 2009 issue of the Texas Logger

November BMP Q&A

By: Chris Duncan, BMP Forester (Ret.), Texas Forest Service

Q: A few months ago you wrote a couple of articles about the planning process which is necessary prior to constructing a forest road. I found these articles to be very helpful, and I would like to know if you have any other information on forest roads.

A: In the August issue I wrote about several tools which should be used when available to help aid in you in the planning process.  Most of these tools are available at little to no cost to you.  In the September issue, I listed several factors to consider when planning your forest road layout.  This month I would like to address the construction phase for new forest roads.

Well-constructed forest roads are essential to forest management activities and are critical in reducing pollution impacts to forest streams.  Poorly constructed forest roads will always be problematic, and are often very costly to maintain or repair.  Improperly constructed forest roads are also usually the main cause of sedimentation into forest streams.  The following guidelines should be used to ensure that roads are constructed properly and to reduce the chances for costly repairs in the future.

Deposits of road building materials are an important resource for forest management activities.  Excavation of these materials represents a potential for pollution into forest streams.  When possible, balance cuts and fills so that the excavated material will be deposited in the roadway fill sections and thereby minimizing the need for borrow pits. To minimize erosion, cut and fill slopes should be designed at the normal angle of repose or less.

Example of a "below grade" road

When constructing a new road, it is important to avoid cutting down to deep and creating a below grade road.  Below grade roads occur when the road’s surface becomes lower than the sides (shoulders) of the road.  Below grade roads act as conduits for rainfall runoff, thereby increasing the chances for erosion and risks to water quality.  Below grade roads are often very problematic, and can be very costly to repair or maintain.

Another important guideline is to implement necessary BMPs during the construction phase.  Following this simple guideline will ensure that the road has maximum protection from erosion both during construction and after construction is complete.  It can be costly to come back in after construction has been completed to fix an erosion problem that may have been averted by installing the proper BMPs during construction.  Installing the proper BMPs during the construction phase will also help to minimize the adverse effects of rain during the construction.

Depending on the sites topography, soil type, streams, and other features; one or more of the following BMPs may need to be installed during the construction phase: crown and ditch, cross drain culverts, wing ditches, rolling dips or broad based dips, water bars, rock or other aggregate materials.

These are just a few of the guidelines that should be considered before any road construction begins.  I encourage you to attend one of our upcoming BMP Forest Roads Logger Training Workshops for more information.

For more information on forest road BMPs and other BMPs visit the Texas Forest Service webpage at http://texasforestservice.tamu.edu/water, contact me at (903) 297-3910.

* This article was published in the November issue of the Texas Logger

September BMP Q&A

By: Chris Duncan, BMP Forester (Ret.), Texas Forest Service

Q:  Last month I addressed some of the tools that are available to use as planning aids for forest road design and layout.  This month I would like to address some planning factors to consider before road construction begins.  Next month I will address the construction phase for forest roads.

A:  Methods to control potential nonpoint source pollution from forestry activities starts with the careful planning of the layout of all operations.  The planning process of any forestry activity is extremely important.  A good plan should maximize efficiency, minimize traffic, preserve soil integrity, and protect water quality.  The following are some of the factors to consider during the planning process.

Are there any previously constructed roads on the property?  If there are previously constructed roads available, it may be less expensive to use the existing road system.  If the existing roads are in good shape, there is a potential for lower water quality impact issues than if you were to push in a new road.  It is important to realize that using “legacy” roads may not always be the best option.  When considering whether or not you can utilize an existing road, there are several factors which may be red flags including:  poor location, not stabilized/washing, poor access to the tract, below grade road.

Another factor to consider is whether your roads will be permanent, temporary, or a combination of the two.  Generally; permanent roads are more expensive to construct,   will require more planning, and will require periodic maintenance.  Temporary roads are constructed for a specific job, and are closed or retired after that operation is complete.

What will be the intended traffic for the road?  This is an important factor, and can also help in determining if the road will be permanent or temporary.  Will the road be used as a skid trail, or will there be heavy truck traffic using it?  It may also be helpful to talk with the landowner and determine if they need access to the tract after operations are complete.  Determine if there will be hunters or ATV riders using the roads or if there will be a considerable amount of vehicles (cars) using the road.

Other factors to consider before road construction begins include but are not limited to:

• Topography - Steep topography will require more water control structures, while flat terrain may have “ponding” issues.
• Soil Type – Some soils aren’t stable enough to support equipment. Sandy soils are generally more erosive than clays
• Erosion/Sedimentation Potential- How likely is it that erosion will occur? Are there any streams nearby that may be adversely affected by erosion? 
• BMPs/Stabilization - What BMPs will I have to use to stabilize road?

These are just a few of the factors which should be considered before any road construction begins.  I encourage you to attend one of our upcoming BMP Forest Roads Logger Training Workshops for more information.

For more information on forest road BMPs and other BMPs visit the Texas Forest Service webpage at http://texasforestservice.tamu.edu/water, contact me at (903) 297-3910.

* This article was published in the September 2009 issue of the Texas Logger

August BMP Q&A

By: Chris Duncan, BMP Forester (Ret.), Texas Forest Service

Q: A few months ago you mentioned that there was a new logger training workshop focusing on forest roads. I have attended both the stream crossing workshop as well as the traditional BMP workshop several years ago. I would like to attend the new workshop when time will allow. In the meantime are there any pointers you could give my company in regards to forest roads?

A: Glad to know that you have attended both the BMP and Stream Crossing workshops. I hope that the information you learned at the workshops has benefited you on your logging operations since then. We should be having another forest roads workshop in the near future. I would be glad to give you some helpful information in the meantime. Over the next few months I will talk about the planning, construction and maintenance of forest roads.

The planning process of any forestry activity is extremely important.  This stage allows you to layout your operations in the most productive, economical, and environmentally sensitive manner possible.  The time spent on planning road design and layout will prove to be invaluable to your business.  The following tools discussed below should be used when available, and are available for your use at little or no charge.

Aerial photographs can be extremely helpful in viewing the entire landscape before any work is done.  These tools can show you the location of existing roads, streams, structures, land uses, and even timber types.  It is important to remember that aerial photographs are a snapshot in time, and are only as good as the date they were taken.  This means that some features on a photo may change in the future, however roads and streams usually remain constant.  These photos are available at the Texas Forest Service, tax assessor’s office, and the Internet.

Topographical maps are also important to use during this process.  These maps show changes in elevation through a series of contour lines.  This can be helpful when laying out the road systems, estimating BMP costs, and avoiding wet areas and steep slopes. Blue line streams are also easily designated on these maps, taking some of the guesswork out of determining if stream crossings can be avoided.  You can obtain these maps from hunting stores, state and federal agencies, and the Internet.

Soil surveys are another tool that can provide a lot of information to contractors.  These books, published by the NRCS, classify the different soil types that are found in an area.  A general description of each soil type is included, along with many charts that contain more detailed information regarding flooding frequency, duration, equipment operability, and much more.  Knowing and understanding the soil type of the property that you are working on can be a tremendous help. For information about ordering or obtaining information about reference copies (CD-ROM or paper copy), contact: tx-nrcs-soils@tx.usda.gov. You can also get soil data from the Web Soil Survey website at: http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm.

Of course nothing beats actually visiting the site in person!  Use the above mentioned tools to get an idea of what you may encounter at the site, and use that information to help you plan your road layout.

For more information on forest road and other BMPs visit the Texas Forest Service webpage at http://texasforestservice.tamu.edu/water, contact me at (903) 297-3910.

* This article was published in the August 2009 issue of the Texas Logger