August BMP Q&A

By: Hughes Simpson, BMP Forester, Texas Forest Service

Q:   A major perennial stream flows through our property and floods at least once a year. These high waters have blown out several culverts and caused severe erosion on the stream banks. Reinstalling another culvert is extremely expensive, so we have decided to retire this rarely used crossing. However, we still would like to stabilize the banks to keep them from washing into the stream. Is there an effective way to accomplish this?

A:   Stream crossings can be very expensive to install and maintain, and if they don’t function properly, can cause major impacts to water quality. These “contact points” are areas where soil can directly enter streams. Retiring old crossings that are not used and stabilizing their stream banks are excellent practices to reduce the potential severity of sedimentation problems.

Restored and seeded stream crossing

There are several effective ways that you can stabilize the stream banks of this crossing. Establishing a good vegetative cover on these erodible sites through seeding will help keep the bank intact and filter runoff water before it reaches the stream. Seed mixes should include a variety of grasses suited for the site conditions present to ensure a high survival rate. Planting in the spring or fall can greatly increase the success of this operation. Fertilizers should not be applied inside the Streamside Management Zone (SMZ) to prevent stream contamination.

Depending on the time of year and the site conditions, grasses may not always grow in these areas. Spreading hay along these banks can also provide erosion control. This method is extremely effective when it is done after seeding. As the hay decomposes, the grass seed begins to germinate and holds the soil in place. This material can be applied more efficiently and evenly distributed using hay blowers. Care should be taken to avoid hay from reaching the stream channel.

Another method that works well is installing rock along the slopes. Securing this material in place can provide great erosion protection and bank stability, however this procedure is generally more expensive than the above mentioned. It is also important to prevent rocks from entering the channel and impeding stream flow.

There are many other techniques that can be implemented to help with this problem, including geotextiles, bioengineering products, and other erosion control fabrics. More information can be found on the Texas Forest Service webpage under the BMP Product and Vendor Guide. If you have a question regarding BMPs, please call me at (936) 639-8180.

* This article was published in the August 2002 issue of the Texas Logger

BMP Informer - July 2002

July Issue of the BMP Informer Now Available

• Your Land is the Future! by James B. Hull, State Forester
• Improving My Land - Streamside Management Zones
• Watch Word…TMDL
• What is a Watershed?
• Texas Forest Service District Offices Serving You 

July BMP Q&A

By: Hughes Simpson, BMP Forester, Texas Forest Service

Q:   My family owns some forested property located near the Red River Valley in Lamar County that we use extensively for recreation. The heavy rains that fell this past winter have caused severe erosion to occur on the main road, making it impassable in certain areas. We tried revegetating it with grass, but the seed did not take, probably because the area is heavily shaded by hardwoods. This is the only road that provides access to the backside of the property and we must be able to drive it. What can we do?

A:   The sandy soils that are typical of the landscape along the Red River Valley are highly erodible. Combine this with the heavy rains we had this past winter and even the slightest topography, and it is extremely difficult to keep your road from washing. However, the use of certain Best Management Practices can prevent this from occurring.

The first area of concern that needs to be addressed is the shading of the road system. Road systems that are heavily shaded do not receive enough sunlight necessary to dry them after storm events. This can lead to rutting and increased washing, which ultimately limits vehicular access. Harvesting trees along the road bank can ensure drying of the road and will go along way in fixing the erosion problem.

The road will also need to be reconstructed in the areas that have severe erosion in order to make them passable again. During the reconstruction process, it is important to consider installing water control devices. These structures are useful in diverting water off the roadway, reducing the erosion hazard of the site. Rolling dips can be used to accomplish this and at the same time, allow truck traffic on the road. A medium sized dozer should be able to handle this task.

To provide additional protection to your road, it would be a good idea to revegetate it again. This activity will help hold the soil in place, stabilizing it so that future washing will be minimal. Since the hardwood trees are not shading the area anymore, more sunlight can reach the seeds, allowing them to germinate. If necessary, fertilizer can be applied to speed up the process of establishing vegetative cover.

Fixing washed out roads can become quite expensive and time consuming, but is absolutely necessary in order to have good access to your property. It also prevents sedimentation from occurring in nearby streams. Finding a contractor that can perform a turnkey operation (harvest the roadside timber, rework, and revegetate the road) on your property will be more economical.

The Texas Forestry Best Management Practices Bluebook can help you with the recommended specifications of constructing rolling dips (p. 45-46) and seeding (p. 61-65). If you have a question regarding BMPs, please call me at (936) 639-8180.

* This article was published in the July 2002 issue of the Texas Logger

June BMP Q&A

By: Hughes Simpson, BMP Forester, Texas Forest Service

Q:   Five years ago, we harvested timber and left an extra wide (200 feet on either side) Streamside Management Zone (SMZ) along an intermittent stream. The erosion hazard on this tract is very slight due to the slope and soil type, and it was reforested the following year. The reason for leaving such a large zone was for wildlife habitat. This property is currently under a hunting lease and by doing this, my lessees will benefit from improved hunting. However, I would still like to thin this SMZ in the future, but do not want to wipe out part of my 4 year old plantation to ensure that a set is not located inside the SMZ. What can I do?

A:   First off, I am very pleased to hear that you have left such a wide SMZ. This will not only provide larger travel corridors for wildlife, but it will also function in greater water quality protection. Maybe now your lessees will understand if the price of their hunting lease rises.

Streamside Management Zones (SMZs) protect water quality and provide wildlife habitat

The Texas Forestry Best Management Practices “Bluebook” recommends locating sets at least 50 feet away from the edge of the SMZ. This will help minimize the chance of erosion and sedimentation from occurring, as well as limit the possibility of a chemical spill reaching the stream. Strict adherence to this voluntary guideline would direct you to construct the set in the newly established plantation.

However, the book also states that SMZs should have a minimum width of 50 feet on either side of perennial and intermittent streams, lakes, ponds, and reservoirs. Since the width of your SMZ was extended past the minimum guidelines for purposes other than water quality protection (wildlife habitat), I do not think it is necessary to clear part of your new plantation for this set. The extra width on your SMZ should give you plenty of room to comply with both recommendations.

During the thinning operation, I would suggest locating the set just inside the area that was left for wildlife habitat. This maximizes the distance from the set to the intermittent stream while allowing you to save your new plantation. The residual density in the first 50 feet along the stream should be at least 50 square feet of basal area per acre, evenly distributed. Skid trails should be minimized in this area also.

If possible, sets should have a slight slope to permit drainage and be on firm, well drained soils that dry quickly. This practice can prevent mud holes from forming. Equipment that is serviced on-site should be done very carefully to avoid spills. Used chemicals should be drained into containers and properly disposed in accordance with all laws and regulations. Any trash associated with the thinning operation should be removed. If you have a question regarding BMPs, please call me at (936) 639-8180.

* This article was published in the June 2002 issue of the Texas Logger

May BMP Q&A

By: Hughes Simpson, BMP Forester, Texas Forest Service

Q:   A network of drainage ditches and canals have been set up throughout the low lying areas of Southeast Texas to function in flood control. Normally, when I am harvesting a tract of timber that borders one of these structures, I protect this waterway with a Streamside Management Zone (SMZ). Recently, I have been asked by the Drainage District on any future harvests to cut up to the banks. This practice assists the district in maintaining these devices. Does this go against the state recommended Best Management Practices (BMPs)? Is there anything I should be aware of when carrying out their request?

A:   I am glad you asked this question. The flat topography that is typical of this area is also sometimes associated with soils that have poor drainage, causing water to pond. Drainage ditches and canals are important tools that can reduce the potential threat from flooding in Southeast Texas. Without these structures, millions of dollars in financial losses could be expected from frequent rain events. Can you imagine the impact Tropical Storm Allison would have had if these devices were not installed?

The Texas Forestry Best Management Practices Bluebook states that “SMZs for man-made drainage ditches should be established if appropriate”. You are to be commended for doing this on your previous harvests. These areas are a little different from springs, creeks, rivers, and other waterbodies in the fact that they are not naturally occurring and their primary use is for flood control. The main objective of BMPs is to protect water quality, so this should always be a consideration when working adjacent to these areas.

After discussing this issue with the drainage district, I understand their reasoning. Sometimes when timber is left along the banks, falling trees or limbs can impede water flow. When this happens, a greater impact to water quality can occur. Removing this debris is very costly and labor intensive, and also slows the implementation of the district’s BMPs. These guidelines, approved by the EPA and TNRCC, require them to re-slope their structures and provide plantings and mulch cover to prevent erosion and stream degradation.

Cutting all the way up to the banks at the request of the drainage district on man-made drainage structures would not be against the voluntary state BMPs. However, certain practices should be followed when conducting forestry activities adjacent to these ditches and canals. It is important that logging and site preparation debris is kept out of these devices and that soil disturbance is minimized in these areas. Bedding operations and other activities should not channel runoff water into these waterways. All herbicide and fertilizer applications should ensure that chemicals remain on site and out of waterbodies. Canal crossings should be avoided unless they are critical and can be installed properly.

This practice should only be conducted on man-made drainage structures and at the request of the local drainage district. Coordination with the district on the timing of harvest and re-sloping of the ditches or canals is crucial. Water quality can be impacted if there is a long time period between these activities. If you have a question regarding BMPs, please call me at (936) 639-8180.

* This article was published in the May 2002 issue of the Texas Logger

 

April BMP Q&A

By: Hughes Simpson, BMP Forester, Texas Forest Service

Q:   I have installed several culverts that have blown out this winter due to high rain events. Last month you mentioned a workshop for county commissioners and road crews that talked about proper culvert sizing and installation? I would like to know how I can prevent my culverts from blowing out, but question whether they should be installed to withstand a 5 inch rain. Is this reasonable? What can I do?

A:   Sorry to hear about your culverts blowing out. Culverts can be used as effective stream crossings, but when they fail, they can be very costly to replace, not mentioning the time it takes to reinstall them, but also the extra sediment that reaches the stream channel. This is why it is so important that proper culvert sizing and installation techniques are used.

It may seem as if a 5 inch rain is not a common occurrence in East Texas and would be hard to plan for, but in all actuality this is not as rare as you might think. This type of rain event does occur, especially in the last couple of years. Installing best management practices (culverts, waterbars, wing ditches, etc.) to safeguard against larger storm events would not be economically feasible and even the best structures would fail during natural disasters.

Before installing culverts, it is important to know the soil type, slope, and how big your drainage area is so you can properly size your culvert. Soils information can easily be found using a soil survey. Topographic maps can help you determine the slope and drainage area of the tract that you are working. To calculate the drainage area, use a topographic map to locate hill tops and decide which way runoff water will drain through a particular point (stream crossing). On a standard 1: 24000 USGS topographic map, one square inch equals 90 acres.

Once you have determined the soil type, slope, and drainage area, you can use a culvert sizing chart to assist you with selecting the right culvert. This chart is found on page 50 of the Texas Forestry Best Management Practices Handbook. Make sure that you buy a long enough pipe so that at least 1 foot extends on each side past the fill material.

Place the culvert in a firm, straight section of the stream channel on a 1-2% downgrade to prevent clogging. There should always be at least one foot of cover to help anchor culverts in and protect them from being damaged by traffic. A general rule of thumb to follow is one foot of fill per one foot of culvert diameter. It may also be necessary to install rip rap, geo-textile cloth, or large stone at the inlet and outlet to reduce erosion and washouts. The approaches to the crossing should be straight and at right angles to the streambed.

Frequent inspections and proper maintenance needs to be performed on all culvert crossings to ensure that they are safe and functional. A clogged or damaged culvert is very susceptible to blowing out under normal rainfall. If you have a question regarding BMPs, please call me at (936) 639-8180.

* This article was published in the April 2002 issue of the Texas Logger

March BMP Q&A

By: Hughes Simpson, BMP Forester, Texas Forest Service

Q:   I am a road building contractor that works mainly on company forestland in Southeast Texas. My employers have developed standards and requirements that I must meet regarding BMPs and protecting water quality when I operate. This sometimes includes extensive training. Do county commissioners and road crews have to undergo a similar process when constructing or maintaining public roads?

A:   You bet! County commissioners are responsible for building or maintaining thousands of miles of roads every year, so they are constantly sending their crews to attend training. This training may include workshops that focus on new techniques, equipment, products, and safety procedures to implement when they are working.

The Texas Forest Service has even gotten involved in offering training to these groups. Ninety percent of all sedimentation (dirt getting into streams) occurs from road systems, clearly showing that erosion from these areas can pose a significant risk to water quality. This risk can be minimized by using Best Management Practices (BMPs), techniques designed to manage water effectively, during the road building process. In order to bring attention to this problem, we are providing water quality awareness training through the Texas Silvicultural Non Point Source Pollution Project.

These workshops are a partnership effort between the Texas Forest Service and local East Texas counties. The judge, county commissioners, and road crews all attend these meetings to get a better understanding of how our operations can impact water systems. These training sessions have already been held for Angelina, Nacogdoches, Upshur, and Morris Counties. Additional counties are being scheduled for future dates.

The workshop starts off with a general overview of the importance in protecting water quality. Every person places a demand on our water resources in one way or another, from drinking and bathing to recreational uses such as fishing or swimming. Impairing our water systems will drastically limit these uses for future generations. Participants understand that their actions in the field can have a direct impact on water quality.

Charles Snowden of the Natural Resources Conservation Services, follows with information regarding the major soil types found in East Texas. Understanding the different characteristics of soils is critical in determining equipment operability, flooding potential, erosion hazard, permeability, etc. Culvert sizing, based on a 5 inch rain, is another major point that is stressed to the group. Improper sizing of culverts can lead to blowouts, which can be very costly, waste time and impair water quality.

The Texas Logging Council Coordinator, Bob Currie, rounds out the agenda. Bob utilizes his expertise from his days with Currie Construction to talk about effective road building techniques. This includes everything from efficient ways to install BMPs to special tricks of the trade. If you have a question regarding BMPs, please call me at (936) 639-8180.

* This article was published in the March 2002 issue of the Texas Logger