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Environmental Restoration02-01-03 | News



Environmental Restoration

Inside the Toolbox

By Dean Murphy








Without question, environmental restoration has come into its own. Many green industry companies across the country are expanding their service lines to include erosion control, wetlands services and reclamation. While environmental restoration can be a natural extension of the services that landscape contractors traditionally provide it is in many ways a whole new discipline. Biologs, wattles and bonded fiber matrix are not everyday terms used by most landscape contractors, unless a contractor focuses on environmental restoration.

Not many years ago, the entire environmental restoration industry revolved around a few very basic operations. Hydroseeding (which entails mixing water, fiber, seed, fertilizer, tackifier and dye in a tank then spraying it onto the raw ground), broadcast seeding (admit it, we have all used a ?EUR??,,????'??whirlybird?EUR??,,????'?? at some point in our landscape careers) and straw bales (staked in to slow the sheet flow or channel flow of water).

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Tough slopes, often need special attention for definitive protection.
A bonded fiber matrix was used for stabilization.
Wattles (top) and biologs (bottom) are commonly found in the restoration toolbox, too.


The last decade has witnessed an explosion of new technology and methodology that has enhanced the value of environmental restoration all across the nation. A better understanding of hydrology and soil behavior has allowed us to provide custom solutions designed to address unique project conditions. Each site has a combined set of circumstances that many times warrant a combined set of approaches to best restore it.

These days the environmental restoration toolbox is large. Wattles (compressed straw rolls) are critical to reclaiming steep slopes. By trenching cross slope and laying wattles in the trenches, sheet flow is slowed and percolation is increased.

A whole family of erosion control blankets has emerged as well. From straw, to jute to coconut, blankets can be selected to deal with different rates of channel flow, address varying speeds of decomposition and regulate moisture absorption capacity. Stream bank stabilization projects are utilizing biologs (rolled fiber filled with cuttings and seed designed to grow in the riparian areas along waterways) to quickly introduce soil stabilizing root structure. For really tough slopes that need definitive erosion protection, bonded fiber matrix is available. (Don?EUR??,,????'???t expect much seeded plant material to penetrate this stuff. It is serious about holding slopes.)






Sides: Steeper slopes, as pictured, may have difficulty with the bonded fiber matrix (top photo). If an area has heavy wildlife, as this project did, the matrix can potentially be punctured, in which case it has a tendency to slide down the slope. Ultimately, a combined set of techniques was required, including hydroseeding and use of the matrix.


Even hydroseeding has evolved, with any number of fibers and tackifiers available. In addition, custom seed mixes have drastically increased long and short-term success rates. In some areas of the country (Colorado for example) colorful wildflower combinations are added to the mix. Jen Sheets, the manager of American Civil Constructors California Reclamation Division has even begun to incorporate custom blended topsoil into the slurry.

Knowledge is critical to most things and environmental restoration is no exception. Information about the existing soil type(s), historic drainage and the proposed use of the site in the future is critical to the success of the project. In addition, understanding the local requirements of governing entities as well as nature remains an important part of the mix. For example, California requires that most environmental restoration work occur in the space of 75 days every fall. (Which makes for interesting 12 month cash flow projections.) The knowledge base of the key individuals who are working on the project is also important. Understanding the way that each piece of the project fits in with another creates a complete system that delivers the results everyone anticipated at the initial job walk.

Any erosion control, wetlands or reclamation project that starts with a well-devised plan has an exponential chance for complete success.

Underestimating the amount of flow that may be experienced in a channel or the reliability of a tributary to keep a constructed wetlands charged are recipes for disaster.








The toolbox is large and most times that?EUR??,,????'???s good. However, confusion over which material to apply in which application is a common problem. For example, the bonded fiber matrix we discussed earlier is lights out on steep slope erosion problems.

That is, unless the slope entertains substantial wildlife traffic.

As deer puncture the matrix and form trails, the matrix has a tendency to slip. In extreme cases it can slip off the slope in entire sheets. Time spent with the vendors who supply the material as well as seasoned veterans who have seen more than their share of 2:1 slopes is a great way to reduce callbacks and excessive warranty work. Knowing what equipment to use is not only and advantage, but a must. Most restoration projects are timed to be completed in short optimum seasons to increase the chances of successful germination and grow in. Production rates become the focus every day as the contractor races the clock. Knowing the limits and capacities of your fleet of equipment directly impacts the schedule.

At the end of the day it always comes down to execution. All the knowledge and planning in the world can?EUR??,,????'???t compete against poor execution. As with other aspects of the landscape business, net income is at least partially a function of training. Better training leads to proper execution etc. The environmental restoration industry has in many ways fallen prey to the mentality of just throw it out there and see what comes up. Lack of education and a rapidly expanding base of technical knowledge have also been contributors to inconsistent execution and a broad spectrum of results. Following industry and product standards goes a long way toward a well-executed project.






The Excelsior soil retention blanket was rolled out and stapled down. The remainder of the area was seeded and hydromulched.


Dave Weigand, who manages the Colorado Reclamation Division of American Civil Constructors, maintains a solid working relationship with his top vendors, local wetlands consultants, soil scientists and hydrologists so that a free flow of product information and creative project solutions are the order of the day. These relationships are vital to the viability of each project.

Don?EUR??,,????'???t be misled about the importance of maintenance in the life of the project. Listing it last is based on the natural order of things – not as an afterthought. Think about it, how many times have you seen silt fence lying down covered in silt, erosion blanket twisting in the wind or straw bales washed into a pile at the bottom of a culvert? Any of these could relate back to the initial execution of the project, but it is just as likely that no one has monitored the site since it was closed out. Monitoring and maintenance are a critical piece of the package. Competent post project evaluation can head off small problems before they become expensive return trips. For example, retucking blanket at the top of a slope after a storm event could save a bank from being blown out and compromising whatever is above it (road, building, retaining wall, etc.). Planned trips to reseed spots where native grasses have not filled in can avoid broadleaf invasions and the subsequent chemical controls needed to eliminate them. Back to the planning aspect, a maintenance plan should be laid out and ready for execution before the install begins.

Overall, environmental restoration contractors are a vital piece of the green industry puzzle. At American Civil Constructors, all types of horizontal construction are performed. From bridges to golf courses, sport fields to highways, typically some sort of environmental restoration or rehabilitation occurs on each project type. Whether erosion control, wetlands or reclamation, environmental restoration is woven into the fabric of our work from coast to coast.

As we continue to broaden our store of knowledge relative to the environment, one thing is clear: with each action there is reaction. Erosion on a construction site may have an effect on en ecosystem several miles away. A constructed wetlands habitat can draw insect and animal species from miles around. As we learn one thing is certain: environmental restoration will be at the leading edge.


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