How long should an erosion or sediment control measure last?
Many Control Measures (BMPs) are temporary by design so it is not surprising that some of them are prone to damage or failure at some point. But how long should an erosion or sediment control measure last? Even very short term construction projects will run 3 to 6 months. And it is not uncommon for projects to be in the active construction phase for 12, 18, or 24 months. We’d like to suggest that a reasonable expectation, even for a temporary control measure, would be a year. Obviously, more durability is better since that would reduce repair and replacement costs.
In this Tailgate blog we’ve written at length about FODS and D Fence, so for this post, we’ll consider those topics covered and look at characteristics of durable BMPs. If you’ve read Erosion Control magazine, you will have seen product ads on almost every page. Too many to cover here. So instead we will propose a list of characteristics that can be used to evaluate possible BMPs for durability.
- Structural strength: A key variable is the strength of the materials used. What is the tensile strength? UV resistance? Ability to withstand traffic? There are more ways to say it, but essentially we want to know the expected life span of the material in question.
- Re-usability: Can the BMP be moved or redeployed on another site? This has to do with more than material strength. Will the item be too full of sediment to move? Will removal of the installation cause damage that render it useless? If it can be re-used, how much labor will be involved and how many times can it realistically be used again?
- Cost over time: Many durable BMPs may have an initial investment or purchase price that is higher than the traditional item it is replacing. Compare the increased price to the number of times it can be re-used or the number of additional months it can operate on the initial installation. Can a cost per month be calculated rather than just a purchase price?
- Maintenance costs: For sediment control measures, is the item easy to clean? Obviously the more effective a control measure is, the more sediment it will capture. That’s awesome if the sediment can easily be removed, but if the sediment buildup cannot be easily removed, it may render the longer lasting control measure ineffective. This would be just as expensive as a throw away control measure.
- Removal and storage: This is related to the maintenance cost, but in some control measures you may have to consider the labor, equipment, transport and storage of a BMP that could be re-used over the course of multiple projects. Can it be removed by one or two workers with a truck or will it need specialized equipment, more people, and an offsite storage solution?
We hope this list of evaluation criteria is helpful, but honestly, we know that not everyone cares to do a full analysis on every product that may enter their site. A much easier process is to ask your BMP contractor (like DTEC!) about durable products in their list of offerings. In this case, a much simpler list of questions will help sort out the viable solutions.
- Is product B more cost effective in the long run than product A?
- If I pay for a re-usable item once, do I own it? Or do I get it back at a reduced cost next time around?
- How long can I expect the product to last compared to the traditional solution?
- Is the new product truly a better choice?
We would love to engage in this kind of dialogue with you. Have you been wanting to try a new product? Are you curious about BMPs you’ve seen on the project across the street from you? Please give us a call and we will be glad to share our experiences to help you make the most affordable and practical choices for your project.