19 Dec Geysersville Streambank Project – LIVE WEBCAM
Hey Everybody!
Let’s talk some COMPOST, shall we!
Compost is such an effective, versatile tool in the world of erosion and sediment control. Sadly though, it seems that it is often misunderstood, misued or too quickly dismissed. A lot of that might be due to a lack of good information out there. So, here at WatchYourDirt and Dirt Time, we thought we’d do our part and try to add some quality information to the mix.
So, we took some really good Compost-centric excerpts from our video and Erosion Draw Software libraries to give you a sampling of what those educational tools have to offer. The video comes from the ‘Big Cover Up’ episode of our Dirt Time video series, while all the other information is taken from the Erosion Draw software tool.
ErosionDraw is a great tool that covers tons of erosion and sediment control techniques, giving not only the full information (description, advantages, disadvantages, comparisions, installation, etc.) but, ErosionDraw also gives access to the full CAD drawings as well.
If the information below looks good to you. You may want to give our videos and software a quick look 🙂
COMPOST BLANKETS
Definition
A compost blanket is a layer of compost designed to prevent erosion, especially rills and gullies that may form under more traditional methods of erosion control. In many cases, a compost blanket can be more effective at vegetation establishment, weed suppression and erosion control than an Erosion Control Blanket (ECB) or Hydroseeding. Compost blankets can be applied by hand, conveyor system or compost spreader; however, the most cost-effective and efficient method is the use of a pneumatic delivery system, i.e. a compost blower truck.
Purpose
A compost blanket is used on slopes to prevent raindrop erosion and in some cases, to increase infiltration rates. A trademarked form of a compost blanket, the Rexius EcoBlanket™ increased infiltration rates and decreased sediment delivery by 99% as compared to bare soil, in a study conducted by the San Diego State Erosion Control Laboratory (Rexius). The success of compost blankets is dependent upon the blanket not being undermined by water; this can be accomplished by keying in the top of the blanket, or the use of a compost berm or sock at the top of the slope. When applied correctly, compost blankets provide nearly 100% surface coverage. (Faucette, 2002)
Advantages
Conditions Where Practice Applies
Compost blankets are usually used on slopes of 2H:1V or gentler, but can be used on slopes as steep as 1H:1V, with consideration given to the length of slope and depth of application (AASHTO). Adding components such as a tackifier, or using compost blankets in conjunction with other techniques can increase the allowable steepness of the slope to be treated. Compost blankets should be extended 3-6 feet over the top shoulder of the slope to prevent water from getting underneath. Compost blankets should not be applied in areas of concentrated flow, and can be used in conjunction with compost berms or socks.
Blankets can be applied in a variety of thicknesses from ½” to 4”, depending upon the intended purpose. As a general rule, the more precipitation an area receives, the thicker the application.
Compost Specifications
There are many types of compost, all with different properties, so it is best to determine what application the compost is being used for. Compost can be derived from feedstocks, biosolids, leaf and yard trimmings, manure, wood, or mixed solid waste, and must be treated with heat to remove pathogens and destroy noxious weeds.
One of the most important criteria for quality compost is the temperature it was “cooked” at and the duration of composting. For instance, California Compost Regulations require that “windrowed compost” be kept at 131°F for 15 days and turned 5 times. Compost manufactured in bags is referred to as “in vessel” which the regulations require be kept at 131°F for only 5 days. Quality compost will then be cured for 60 days (D.Carvalo, personal communication, 2004).
Click Here for California Department of Transportation Specifications for Compost Blankets
Installation
Compost blankets can be applied in a variety of ways, however the most efficient and cost-effective way is through the use of a pneumatic blower truck.
GET MUCH MORE INFORMATION:
For MUCH MUCH more information on Compost Blankets and Berms including CAD design drawings, pick up a of Erosion Draw software!!
For more video, you can purchase our ‘Big Cover Up’ DVD or go all out and get the Dirt Time Ultimate Set – which contains our Big Cover Up episode, as well as Compost applications in 3 other episodes.
Tons of information is right at your finger tips – all available through the WatchYouDirt and the WatchYourDirtStore.
Any questions or comments, give us a ring in the comments below!
Stillwater Creek
Biotechnical Streambank Stabilization Workshop
With John McCullah and David Derrick
May 8th – 11th, 2012
Shasta College
Redding, CA
Email Info@salixaec.om or phone 530-247-1600 for more info.
Found this great stormwater video while travelling the Internet the other day 🙂 It’s a great primer for stormwater education. Have a watch!
-John
Hey Everybody,
We’re thinking of doing a series of posts about different Erosion & Sediment Control and various Streambank techniques. Kind of a basic knowledge, information-rich, get-to-know-your-tools type of thing. So, let’s give it a go shall we?
Let’s talk Live Silitation!
TWO QUICK NOTES
DESCRIPTION
Live siltation (also known as Vertical Brush Layering) is a revegetation technique used to secure the toe of a streambank, trap sediments, and create fish rearing habitat. The system can be constructed as a living or a non-living brushy system at the water’s edge.
PURPOSE
Live siltation helps to secure the toe of a streambank, and trap sediments.
CONDITIONS WHERE PRACTICE APPLIES:
Live siltation is an appropriate practice along an outer bend with sufficient scour or toe protection.
PLANNING
Useful for Erosion Processes:
Spatial Application:
Hydrologic / Geomorphic Setting
Design Guidelines / Typical Drawings:
Cuttings should be placed adjacent to the water’s edge to ensure effective sediment trapping and velocity reduction at the toe of slope. At least 40 branches per m (12 branches per ft) should be installed.
ENVIRONMENTAL CONSIDERATIONS / BENEFITS
This is a very effective and simple conservation method using local plant materials. This technique is particularly valuable for providing immediate cover and fish habitat while other revegetation plantings become established. The protruding branches provide roughness, slow velocities, and encourage deposition of sediment. The depositional areas are then available for natural recruitment of native riparian vegetation.
HYDRAULIC LOADING
This technique may be used for velocities up to 2 m/sec (6.6 ft/sec), but velocities should be at least 0.25 m/sec (0.8 ft/sec) for the system to function properly.
COMBINATION OPPORTUNITIES
Live siltation techniques can be constructed in combination with rock toes, Rootwad Revetments, Coconut Fiber Rolls, Live Fascines, and Brush Mattresses.
ADVANTAGES
This is a very effective and simple conservation method using local plant materials. This technique is particularly valuable for providing immediate cover and fish habitat while other revegetation plantings become established. The protruding branches provide roughness, slow velocities, and encourage deposition of sediment. The depositional areas are then available for natural recruitment of native riparian vegetation.
LIMITATIONS
If using a living system, cuttings must be taken during the dormancy period.
MATERIALS AND EQUIPMENT
Natural stone, willow wattles, logs or root wad revetments are needed for toe and scour protection. The live siltation will require live branches of shrub willows 1-1.5 m (3.5–5 ft) in length. The branches should be dormant, and need to have the side branches still attached. Any woody plant material, such as alder, can be installed for a non-living system.
CONSTRUCTION / INSTALLATION
Construct a V-shaped trench at the annual high water (AHW) level, with hand tools or a backhoe. Excavate a trench so that it parallels the toe of the streambank and is approximately 0.6 m (2 ft) deep. Lay a thick layer of willow branches in the trench so that 1/3 of the length of the branches is above the trench and the branches angle out toward the stream. Place a minimum of 40 willow branches per m (12 branches per ft) in the trench.
Backfill over the branches with a gravel/soil mix and secure the top surface with large washed gravel, bundles/coir logs, or carefully placed rocks. Both the upstream and downstream ends of the live siltation construction need to transition smoothly into a stable streambank to reduce the potential for the system to wash out. More that one row of live siltation can be installed. A living and growing siltation system typically is installed at AHW. A non-living system can be constructed below AHW during low water levels. If it is impossible to dig a trench, the branches can be secured in place with logs, armor rock, bundles made from wattles, or coir logs.
COST
0.7-2 work hours per linear m (0.2-0.6 work hours per linear ft), plus willow stock if not readily available on site.
MAINTENANCE / MONITORING
During the first year, the installation should be checked for failures after all 1-year return interval and higher flows, and repaired as necessary. During summer months of the first year, ensure that cuttings are not becoming dehydrated.
COMMON REASONS / CIRCUMSTANCES FOR FAILURE
Cuttings will not promote siltation as well if not located at the water’s edge. If located further up the bank, cuttings may dry out, and will only trap sediments and slow velocities during high flows. Cuttings may not grow well if not handled properly prior to installation. See The Special Topic: Harvesting and Handling of Woody Cuttings for proper handling instructions.
Download the Registration / Information PDF for the Advanced Workshop here
IT’S FILLING UP FAST!
REGISTER NOW!
Hey All
Remember the Schenk Creek project? It was the little seasonal creek below Highway 330 in San Bernardino National Forest that got inundated with DG sediment when a landslide occurred in the winter of 2010. Remember District 8 had to design and build some really huge wire mesh-reinforced walls and also remove over 16,000 CY of material from the creek.
I got called in to restore the stream. See this post for more information.
Well, Jason Bill recently sent me some photos taken on August 3rd – Three months later. See how well the willow worked when incorporated into the restoration work.
The most interesting and informative techniques/prescriptions used for the stream bank stabilization included Longitudinal Stone Toe (LST) , Live Siltation , and the RSP Soil Flapping. The LST and Live Siltation techniques are available in the ESenSS Manual (or NCHRP Report 544) and the RECP Soil Flapping Technique comes from a recent course we are teaching for Caltrans Landscape Architecture (See https://www.dot.ca.gov/hq/LandArch/ec/steep_slopes/recp_wrap.htm)
The Soil Flap method is really beneficial for steeper slopes (>2H:1V) that require a some reinforcement. The horizontal element embedded in the slope provides geotechnical reinforcement while the “flapping” element provides erosion control. Soil Flaps are not as strong as Soil Wrap but they are super cost-effective and constructible!
https://www.dot.ca.gov/hq/LandArch/ec/steep_slopes/recp_flap_with_brush_layering.htm
Just a reminder that these techniques and more are available on ESenSS or in the NCHRP Report 544, 2005. See index to techniques PDF
Hope you all recall that soaking willow branches for a few days to a month will increase the successful establishment.
Some more photos here to see how the structures were built in Schenk Creek back in May.
Hope to see you all out in the field and keep your willow branches wet!!
-John
Email us at info[at]WatchYourDirt.com
or call: (530) 247-1600
Download the Registration / Information PDF for the Advanced Workshop here
IT’S FILLING UP FAST!
REGISTER SOON!