Digging With the Best

    March 1, 2001
    As contractors consider the merits of undertaking projects in erosion control (which might involve landscaping, roadbank stabilization, and wetland and riverside projects), they are wondering which machines are best for the work. Do I need a new large excavator, backhoe, or dozer, or can some of today’s compact and less expensive machines handle the work efficiently and cost-effectively? We have learned from talking to professionals all over the country that there is no perfect machine that is the best for all jobs and that local conditions usually determine the way to proceed. Changing patterns of growth in a community can alter a contractor’s thinking about the best machinery to use for a particular job. Slopes, wetlands, gullies, and ditches that were considered remote and rural a few years ago might now be at the very center of a residential development, and the equipment used must not damage property or endanger the ecology of the site. For John Perkins, a landscape contractor based in Minneapolis, MN, environmental concerns within a large city might seem pedestrian compared to working in pristine natural areas. He discovered that for his customers, though, they are every bit as important. “Whether I’m working for a city or a private homeowner, environmental concerns are just about always there,” he notes. “Whether a city needs us to work in environmentally sensitive marshes or a homeowner is concerned about turf damage, we have a Posi-Track that allows us to work and not worry about causing damage.” This crawler-tractor-loader is manufactured by ASV in Grand Rapids, MN, an affiliate company of Caterpillar. It offers very low ground pressure, which is a welcome benefit for many projects on slopes and riverbanks or along ditches.The Nearer the Water, the Greater the CarePeople who are involved daily in erosion and sediment control, landscaping, and soil stabilization understand the dangers of the reckless use of construction equipment, especially near the shorelines of lakes and the banks of streams. In Hamilton County, NY, where there are many lakes, the Soil and Water Conservation District (SWCD) distributes leaflets describing good and bad practices for homeowners and landowners. The leaflet “Save That Lake!” is worth reading; your local SWCD might offer one too. For inexperienced contractors, the explanations will make it clear why certain machines are preferable to others. The water from roads can contain sediment, phosphorus, and pollutants from traffic, so excavators and loaders that leave channels behind them creating easy runoff from roads to streams and lakes are not recommended. Ground pressure is important, especially when the weather is unhelpful and the ground is less firm. If smaller machines, such as skid-steer loaders, small backhoes, and compact excavators, can achieve the specified digging and ground preparation results, they will probably do so without the deep damage and disruption caused by bigger equipment. Contractors (and logging companies) use temporary access roads in the wetlands in the Adirondack Mountains and other places nationwide, and there are strict and sensible regulations for their construction and use. “Most of the contractors are savvy people,” comments Ken Kogut with New York’s Department of Environmental Conservation (DEC) in Lake Placid. “They build their access roads and know which equipment will not harm the wetlands. We require a mat of some kind – and there are various types available – for temporary crossings of wetlands.” Geotextile fabrics have been popular; you regularly see sources for them in Erosion Control. “The contractors come in and unroll the mats for access roads from their trucks or loaders,” adds Kogut. “When they have finished that project, they roll up the mats again and take them away for the next job. The size and weight of the equipment is important, so compact machines will work well as long as they have the power to do the specified work. Our regulations try to prevent these access roadways from becoming big mud holes, so we also recommend that the machines used have floating tracks.”Local Conditions Dictate the Rules
    This rubber-tracked machine managed multiple landscaping jobs in Minnesota with no damage.
    Completing the work with minimal disturbance is the compact excavator’s goal.
    As cities expand, so does the need for careful, compact equipment.
    Once a compact excavator passes through narrow entrances, its work envelope can be surprisingly large.
    Low ground pressure is especially important near water.Coon Rapids, MN, had a problem that demonstrates how conditions change in a community. Over the years the city allowed an area around a drainage ditch to become overgrown with vegetation that effectively clogged the system. In the process, however, the area became perceived as a wildlife area that the city and homeowners actually wanted to preserve. On the other hand, the city still needed to open up the drainage system. “The city was considering using a backhoe to dig a big circle around it, but that would have pretty much demolished the pond and the wildlife area,” says Perkins. “We used the Posi-Track to go through the center of the area where other machinery couldn’t go, and we opened up the inlets and the outlets, which had been plugged. The homeowners association came out to watch to make certain we didn’t harm anything, and they left happy.” On a similar job in Coon Rapids, Perkins was asked to remove grass and sediment that had built up along a drainage ditch through a residential area. “Before the development, the city could use a backhoe to dig the ditch, but now the city has grown up along the drainage ditch, so there is no easy access to it anymore without causing a lot of damage,” notes Perkins. “We went in and drove on people’s lawns while clearing the ditch – with no damage.”“I wouldn’t run anything but a four-wheel drive,” declares Craig Kratzberg, owner of CE Construction in Palmdale, CA. Bidding on jobs that are within two hours north or south of his base in the Antelope Valley area, he encounters all types of soils. “I’ve done jobs near Santa Barbara, where there’s a lot of silt and clay, and the smallest amount of rain can make that stuff pretty slimy. I’ve also had jobs at Edwards (Air Force Base near Mojave, California), and the spoil there varies from loam to an eroded, flaky granite that can be ripped up with a box blade. I’ve done work in Fillmore [in southern California] where the building sites were on old riverbeds, and you’d end up with rocks as big as 2 feet across. With the different soil conditions, you can get into a real mess, and I’ve found that the few extra dollars for the four-wheel drive are worthwhile. It is a lot more productive.” Kratzberg has owned a number of New Holland 4WD tractor-loaders; his current models include a 260C and a 545D. “The tractors I use have a low center of gravity, and that is what you want on slopes. My 545D is stable and has good rollover protection, and I like the narrow profile when working near trees.”Good general contractors find themselves winning bids for projects that offer new challenges for their equipment and crews. “We use both large equipment and compact equipment, depending on the application,” comments Don Diehl, owner of Diamond D Ranch Contracting in Abilene, KS. He manages projects that include work for the Trinity River Authority in Texas, the US Army Corps of Engineers, and the State of Kansas. “Slopes require stability, which you associate with a bigger machine, but Bobcat skid-steer loaders can handle that kind of work too. It’s a question of matching your productivity requirements to the ground conditions and environmental concerns.”
    A Change in the Leadership?
    There are practical, easy-to-change attachments for compact excavators as long as you have the necessary power.
    Once in position, compact excavators usually require less repositioning than do old-style backhoes and excavators.
    This bucket swing attachment gives up to 180o of swing.A few years ago, backhoe loaders might have been the obvious machines to use for landscaping, soil erosion, and bank work. They are among the most popular machines seen today and available in a good range of sizes, but another type of machine seems to be threatening their traditional position of leadership in this market. The compact excavator (called the mini excavator by some) has been popular in Europe for years but has only recently started to obtain fans in North America. It’s not simply because this kind of excavator is smaller and can access difficult corners of a project. The technique used brings change too. Compact excavators (such as the D Series from Bobcat) are intended for excavation and trenching, and one of their main features is that the operator’s position is offset to give a better view of the work. The operator rotates with the upper structure to lessen fatigue from frequent head movements and to allow faster repositioning, with no stabilizer or bucket to raise and reset. The compact size of the machine – the smallest Bobcat excavator is less than 39 in. wide – lets it travel to sites inaccessible to larger machines, even through garden gates, and its minimal tail swing (with no loader bucket in the rear) reduces the room it requires for its work. The Bobcat house or cab rotates 360º, meaning that the bucket can dig in any position without interfering with the operator’s visibility, while loading and dumping spoil can be in any direction.The tracks of the undercarriage are counterrotating for good maneuverability. One of their advantages, mentioned by a contractor who was working on slopes by a highway, is that they do not leave ruts as do the wheels of some machines. Another practical advantage, praised by several contractors in states where the weather dictates the length of the working season (most of the northern ones), is that the increased flotation of a tracked undercarriage allows work in muddy conditions and on those awful days when rubber-tired machines can bog down with little or no productivity. In addition, the rubber tracks (with low ground pressure) will not damage hard surfaces, such as driveways, sidewalks, or paths. How do you transport a compact excavator? It is light enough to be carried on a small trailer behind a pickup truck.One of the essential requirements for skid-steer loaders, backhoes, and compact excavators is that they have enough hydraulic power to run the many attachments available for them today. Bobcat has more than 60 attachments available for its skid-steer loaders and reminds us that the biggest attachments are not designed to work on the smallest machines. Other manufacturers, such as Gehl, Mustang, Kobelco, Hitachi, Caterpillar, Case, New Holland, Komatsu, John Deere, Takeuchi, Kubota, Daewoo, Thomas, Hyundai, Compact Technologies, and JCB, will say the same. Make sure that your carrier machine has enough hydraulics to run the attachment you want for it and engine power to enable all the functions required.Two very different projects, one in Wisconsin and the other in Idaho, show the versatility of compact equipment. When cleaning the ditches that keep the water flowing in the cranberry beds near Wisconsin Rapids, WI, Mike Bennett of Bennett Cranberry Company uses a Bobcat 331 compact excavator. He does own a larger excavator for jobs where a long reach is required. “I prefer using the 331. The boom and bucket move so much faster. After cleaning the ditches, I place the debris on the road on top of the dikes and use the blade to level it out. The material dries faster, and I don’t have to till it in. Also, using the blade means I don’t need another piece of equipment.” At the 22-mi.2 USEPA Bunker Hill Superfund site in northern Idaho, Environmental Reclamation Inc. (ERI) uses as many as 27 Bobcat machines, skid-steers, and compact excavators. Operators and machines work 10-hour days, seven days a week in the peak season. Although the project is large, it is broken up into small areas; ERI is removing the top 12 in. of soil from thousands of home sites and about 500 business sites and replacing it with new material. “We put several years of operation on the machines in one summer,” notes Pat Walters, one of the owners of ERI. “We work the machines hard, and they have proved most reliable.” On the Right Tracks
    The PowerTilt helps clean up and bevel both sides of a ditch from one position.Tracks seem to make a great difference in the speed and efficiency of any job that involves slopes, so there are contractors who prefer to have a rubber-tracked compact loader rather than a skid-steer loader with standard wheels (though the latter can be fitted with rubber tracks by some manufacturers). The experts at DEC in New York insist on flotation tires for equipment making temporary crossings over wetlands. Manufacturer Takeuchi, for example, offers compact track loaders and track excavators, its first model of the latter designed back in 1971. Digging depths for Takeuchi compact excavators range from 5 ft., 1 in. to 15 ft., 2 in. The maximum reach at grade is 8 ft., 11 in. for the smallest (TB007) and 23 ft., 9 in. for the largest (TB175).
    Landscape companies love the new power and high-flow options available on skid-steer loaders.
    Accuracy and low ground pressure make compact excavators useful, even when there are no adjacent buildings.

    Contractor J&J Crisafulli has seeded tens of thousands of acres in Montana, where most of the terrain is quite the opposite from the lake country of New York. Many of the sites are along railroads, in cuttings where the slopes are as steep as mountains (because that’s what they are). “Before placing the seed and mulch on slopes, we make sure those slopes are in the right condition to accept them,” states Joey Crisafulli. “We have found tracked dozers good for going up and down slopes, but some of these new machines that can automatically adjust their balance seem to work well by going along the slopes. They seem to eliminate that fear of toppling over. Stability is essential for any work on slopes from the standpoint of the operator’s safety and the efficiency of the work.”

    “Ride control” is what Case calls its antipitching system on the XT Series skid-steer loaders. It reduces the pitching caused by the motions of the machine when loading material and when driving on irregular surfaces. “We have several Case XT skid-steers,” says Marv Wyatt, whose Key West Retaining Walls cover the western side of the country. He has skid-steers based in his Seattle, Portland, and Los Angeles offices. “We use them to get into small spots where our other machines cannot access. They have lots of power and can load our pallets, which usually weigh 3,500 pounds, with no problem.” Wyatt comments that he has been impressed by the really low maintenance of the XTs. Key West’s most frequently used attachments are pallet forks and buckets, but they mount a backhoe occasionally if the site requires it. “One of the most useful attachments for our skid-steers is the Grouser tracks. It is simple for our crews to put them over the wheels, and it gives not only better flotation but a greater load capacity. The tracks are safer on some of the terrain where we work too. Rain and mud are not uncommon in Seattle, for example.”Owners of Kubota tractors and compact construction equipment give us a good idea of what they expect from their machines by the comments they make about the ones they own. “It turns easily and doesn’t scar the turf like others,” observes John Lake, whose operations are in Lexington, KY. “What I like about Kubota is it makes the right-size machines for the job,” comments Mike Rudinsky, also in Lexington. Note that he did not say the “biggest” machines but ones of the “right” size. Harold Austin in Yakima, WA, likes the fact that the Kubotas are operator-friendly and it is easy for him to train new operators. Regarding the actual operation of compact tractors, Pat Werdin in Hayesville, NC, praises his Kubotas as “extremely easy to operate,” and in North Branch, MN, Milo Behrendt adds that his are “cheaper and quieter to operate.” The features that users single out about any piece of equipment reinforces the fact that some of your best resources for knowledge about equipment suitable for erosion control, drainage, and soil stabilization are others who have good experience in this type of work.Bigger and Bigger?
    The dumping height of this skid-steer loader might be surprising.Skid-steer loaders started as little ants in the construction industry, endlessly working, loading, and carrying, and then doing more and more as the number of attachments available grew almost exponentially. They have grown, becoming much bigger and more powerful, to a level where it is difficult to say if the largest skid-steer loaders are really the same machines as yesterday’s little workers. The story of compact excavators is similar. Attachments have been developed to match each new size. One of the attachments familiar to owners of excavators and backhoes, especially those involved in ditch work and erosion control, is the PowerTilt from Helac Corporation of Enumclaw, WA. This hydraulic swing attachment gives up to 180º side-to-side bucket swing. A new model is now being used on smaller machines, such as Bobcat’s compact excavators. The concept behind the PowerTilt is to make the carrier machine work more quickly by enabling the operator to adjust the angle of a bucket relative to the work instead of repositioning the whole machine. For work on slopes and ditches, the swing attachment allows the operator to position the bucket at different angles. By moving the carrier machine less frequently, an operator could save as much as an hour a day.If equipment that occupies less ground space, weighs less, and costs less is available, contractors will consider all its advantages or disadvantages vis-à-vis larger machinery. Some aspects for consideration of machine size are production rates, labor requirements, cost of fuel, convenience of transportation, ease of access to the site, and the machine’s innate versatility. The type of machine you require is probably available in a compact configuration. To reiterate a previous remark: The first requirement is that it must handle the necessary work. After that, the advantages will probably relate to operational costs. Can the compact machine achieve the results you want as quickly as you want them and more economically than larger equipment? The answer for many projects will be “Yes.”