For those of you who have read my column over the years, you know that the four foundational building blocks of business are strategy, execution, people and cash. For you first time readers—now you are in the know. For any company to be tremendously successful, you must be good at all four of these business cornerstones and always evolving. While well-executed strategy is a critical and unique secret sauce that differentiates your company from the rest of the pack, and cash is the oxygen that must flow in and out daily for the business to remain healthy—it is your people who are the soul and brain of your organization.
So why is it that so many companies cannot keep or attract great people? Research shows that less than 40% of our workforces are engaged, motivated and happy, and therefore, they perform at a level below their capabilities. A big part of the problem comes from the top leadership and the bureaucracy created by leadership—either consciously or unconsciously. In my experience, I have witnessed both scenarios, and I have often said the bottleneck starts at the top…every pun intended.
In fact, the burden of bureaucracy seems to repel a team’s creativity and motivation. I do not know about you, but I’ve been-there, done-that. I remember that awful feeling when working with a leadership team neck deep in bureaucracy that drained the life and soul out of me.
Remember, people do not leave companies, they leave people. So, what can we do about it? Begin by taking an objective look at your leadership team, organizational structure and key processes in revenue producing functions like sales, estimating and billing. Does your leadership have the skill sets necessary to take the company to the next level, and do they have a strategy designed with the input of the team? Do they solicit feedback and ideas from everyone? How many layers and ineffective processes have been created over the years within the organization?
Do not get me wrong—processes are key to your success. The problems occur when leadership has not unleashed the powers of their people so they can use their creativity and talents to evolve, improve and make things easier for everybody. People have a strong internal desire to work with a team of people who share a common vision and who feel motivated, inspired and challenged to bring and showcase their skills and talents to work each day. A place where ideation versus conformity is encouraged. An environment where talent, risk-taking and contributions are rewarded versus your position or how well you play internal politics.
Most leadership teams do this unconsciously, believing there is great value in control and consistency. I encourage each one of you to sit down individually and as a team to address these issues. The goal is to build a company that focuses on maximizing everyone’s human potential and contributions. If you succeed, I guarantee that your greatest challenge will be having too many talented people knocking at your door.
Judith M. Guido, MBA, is the chairwoman and founder of Guido & Associates, a business management consulting firm in the erosion control and green industry. Guido can be reached at 818.800.0135 or judy@guidoassoc.com.
Erosion pedestals near the trunk of a standing snag, indicative of raindrop splash erosion, which may have been an important driver of high sediment yields in burned-only plots. Photo credit: K. D. Bladon.
By Rich McLaughlin, Ph.D.
While many parts of the world have a long history of fire as part of the ecosystem, climate change appears to be making these fires more intense, affecting larger areas over longer periods of the year.
The response of the landscape to these fires was the subject of an extensive study of post-fire landslides in a chaparral-dominated mountain area of Southern California.1 The authors focused on landslides and debris flows that occurred in response to a heavy rainfall event in January 2019.
The rainfall totals ranged up to over 300 mm over several days, with intensities up to 50 mm/hr. Orthophotos and aerial lidar data were obtained for the area before and after this event and used to find 286 landslides caused by this event. The areas investigated were either unburned or had wildfires occur from 1 to 10 years prior to the rainfall event. Areas that had burned a year before the storm produced debris flows, while those burned three years before the storm had much smaller landslides with an order of magnitude less erosion. By five years after a burn, landslides and erosion rates were similar to those of unburned areas. Most of the landslides occurred on south-facing slopes that were slower to revegetate. The authors concluded that vegetation is a critical factor in landslide activity, and in this area, landslide activity may return to “normal” within five years after a burn.
Two other studies in California examined the effect of post-fire logging and management on erosion relative to unlogged, burned areas. Olsen et al. (2020) collected sediment from either burned or burned with salvage logging areas for five years after a fire in central California.2 They looked for the effects of logging on specific factors, including rill density, bare soil areas and ground cover (including woody debris). Logging did not increase erosion, but skid trails, where logs are dragged to a transportation area, tended to have higher rill density and sediment losses. Waterbars used to divert water off skid trails often channeled the rill flows toward the drainage areas of the slopes.
Subsoiling to decompact skid trails tended to increase erosion, although it was only practiced on two of the nine logged areas. Because bare soil areas were often where rills initiated, the authors suggest that supplemental mulching after fires would be a good management practice. In a similar study, Cole et al. (2020) also measured erosion in burned areas and compared the effects of either logging or logging plus subsoiling relative to the burned areas left alone.3 Like the previous study, they established silt fences on slopes to collect sediment over a period of five years. The logging activities reduced the amount of bare soil due to the cover from the debris left behind and resulted in less erosion compared to the burned areas with standing timber. Subsoiling along the contour, while creating localized bare soil areas, reduced sediment transport by increasing roughness and interrupting flows. The authors observed that the standing, burned trees tended to create much larger water drops than the natural rain, and this resulted in more erosion in the bare soil under the canopy (Figure 1). Overall, both studies found that salvage logging after fires can actually reduce soil erosion in burned areas.
Rich McLaughlin, Ph.D., received a B.S. in natural resource management at Virginia Tech and studied soils and soil chemistry at Purdue University for his master’s degree and doctoral degree. He is a professor and extension specialist in the Soil Science Department at North Carolina State University in Raleigh, North Carolina, specializing in erosion, sediment and turbidity control.
References 1) Rengers, F. K., L. A. McGuire, N. S. Oakley, J. W. Kean, D. M. Staley, and H. Tangengers. 2020. Landslides after wildfire: initiation, magnitude, and mobility. Landslides 17, 2631–2641. https://doi.org/10.1007/s10346-020-01506-3.
2) Olsen, W. H., J. W. Wagenbrenner, and P. R. Robichaud. 2021. Factors affecting connectivity and sediment yields following wildfire and post-fire salvage logging in California’s Sierra Nevada. Hydrological Processes. 2021;35. https://doi.org/10.1002/hyp.13984.
3)Ryan P. Cole, R. P., K. D. Bladon, J. W. Wagenbrenner, D. B. R. Coe. 2020. Hillslope sediment production after wildfire and post-fire forest management in Northern California. Hydrological Processes 34:5242–5259. DOI: 10.1002/hyp.13932.
Erosion pedestals near the trunk of a standing snag, indicative of raindrop splash erosion, which may have been an important driver of high sediment yields in burned-only plots. Photo credit: K. D. Bladon.
CHALLENGES OF EROSION AND SEDIMENT CONTROL FOR WATERCOURSE PROJECTS
By Heather Amirault, P.E.
The traditional role of erosion and sediment control (ESC) is to keep sediment from construction sites, with a particular emphasis on keeping sediment out of natural areas. It is especially important to keep sediment out of sensitive natural areas like watercourses and creeks. However, what happens when your construction site is a sensitive natural area? What about when your goal is to complete a project in a watercourse? Or when your project is a watercourse realignment or restoration?
Stream projects in Canada are typically initiated through the need to protect infrastructure. Examples include bank stabilization to protect a trail or pipeline, or channel realignment to accommodate a culvert extension or new road alignment. Once a project begins, the main regulatory influence is the Fisheries Act, which guides work in and near fish habitat and has a goal of preventing “harmful alteration, disruption or destruction of fish habitat.” Harm could include changing the water flow, reducing the amount of wetted area habitat or depositing harmful substances in a watercourse or waterbody. Under the Fisheries Act, sediment deposited in a watercourse is considered a harmful substance.
In some jurisdictions and/or during emergency response, regulatory agencies will allow “in-water work,” which is permission for a contractor to complete restoration works in live flow (i.e., excavators working right in the creek). The capacity of the watercourse to absorb a certain amount of construction-generated sediment is relied on during these in-water works. The ability to work rapidly while seeing the precise impact of each placed or formed feature is considered to be enough of a benefit to outweigh the cons of temporary construction sediment releases on the downstream habitat. In Canada, due to the focus on preventing harm to fish habitats, permission for in-water work is rarely given. Therefore, those managing Canadian restoration projects typically have to put a lot of thought and consideration into how to manage water and flows during construction. This consideration is necessary because managing water and flows is directly related to managing sediment, and therefore directly related to protecting aquatic ecosystems downstream of your project.
So, how do you do work in a watercourse without getting wet? How do you do work in a creek without changing the flows and affecting fish habitat downstream? You can’t just turn off the water. Water needs to continue downstream so fish habitats don’t dry out and leave fish stranded. It’s also not enough to just install some silt fence or a temporary sediment basin. The traditional land based ESC measures are typically not effective in water bodies. The usual regulatory requirement for working in a watercourse is that construction must take place “in the dry,” meaning the construction site must be isolated from creek flows. Working in the dry keeps watercourse flows separated from the construction area, limiting construction impacts on water quality. But how do you keep flows separate from your construction area when your construction area is a watercourse?
One way of looking at the problem is to think like a traffic engineer doing highway construction on a major highway. You can’t just close a major highway for a few months to get the work done, you have to keep the traffic (in this case, water) moving. On a highway project, you can use techniques like reducing lanes and providing detours. The equivalent of a lane reduction for a watercourse project would be to use a flume or pipe to move flows through the site, isolating flows from the rest of the worksite. The equivalent for a detour would be to dam and pump the flows around the site or to create a diversion channel. Sometimes new roads are built away from existing roads, and construction only disturbs existing traffic patterns at either end of the new road segment where it gets connected to the existing road network. In watercourse restoration work, building outside the existing channel footprint is known as offline construction. Offline construction keeps the new channel alignment far enough away from the existing channel alignment that flows can continue business as usual through the old channel until the moment comes to flip flows into the newly constructed channel. When only completing work on one side of a channel, turbidity curtains may provide adequate separation of the turbid construction waters from the clean flows in the rest of the watercourse.
Sometimes highway construction strategies involve closing entire highways overnight when traffic volumes are lowest. Complete closure won’t work for creeks. You will still need a detour. The closest equivalent would be completing the work in the lowest flow season, which is typically mid-summer in most of Canada. Timing the work around low-flow periods means you don’t have to have a system that must constantly manage or divert high flows from spring runoff or large fall storms. But what about large rain events or floods resulting in higher flows than the site isolation system can handle?
As discussed, managing the instream flow is a critical part of ESC on a watercourse project. However, we can’t stop at just managing these typical instream flows. The water on creek project sites comes not only from the upstream channel but also from the sky and overland. Additionally, flows within the watercourse are not constant, particularly in urban settings where instream flows are very responsive to precipitation events. Therefore, not only must we protect the watercourse by keeping instream flows separated from the construction area, but we must also keep the watercourse construction area protected from erosion and sedimentation.
Everyone has seen a newly graded site with fresh topsoil exposed. The site is vulnerable to erosion until vegetation is established. Watercourse sites have this same vulnerability but are at higher risk due to the chance of flooding. Leaving exposed soils on the valley walls, floodplain and channel banks is typically not an option as you are almost guaranteed to have erosive flows move through your work area at some point during construction or soon afterward. To reduce the exposure to flood risks during construction, it is typical to proceed by working on small sections of the new channel. This construction sequencing limits the amount of exposed and disturbed channel between the newly constructed (stable) section and the existing undisturbed section of the channel. In this way, the small, exposed disturbance area can be quickly stabilized with temporary rock protection or matting in preparation for a large flow.
Large flows can be anticipated by monitoring predicted precipitation in the weather forecast. Ultimately, as with any other site with exposed soils, the best thing you can do for a watercourse project site is to stabilize the soil with vegetation cover. Unfortunately, the vegetative cover is not instantly available, therefore interim measures are included to keep the site stable until the channel bank and floodplain vegetation becomes established.
Some of the stabilization measures commonly applied at watercourse sites include coir-wrapped soil at banks and biodegradable erosion control blankets on floodplain and valley walls. Beyond these surface measures, the design of channel and valley forms can be used to reduce erosion potential. A channel set within a low floodplain can be designed to spread high flows out over the floodplain. This connection to the floodplain reduces the shear stress and erosion potential from high flows and floods, promoting stability within the channel and valley.
The long-term stability of a creek site relies not only on the channel and valley form, but also on the successful establishment of vegetation. When developing a naturalization planting plan for a watercourse project, we consider the use of native tree and shrub species that don’t mind having wet feet; species suited to growing near water that can handle being flooded occasionally. The seed mixes selected for application over the floodplain and valley walls usually include a cover crop mixed in with a perennial native seed mix. In this way, the cover crop can grow quickly and provide some stability for the slower growing native perennials. Planting plans will often include the use of live stakes along watercourse banks. This form of shrub planting is inexpensive, easy to install and provides the long-term benefit of dense riparian growth with strong roots to stabilize the creek banks.
When your goal is to complete a project in a watercourse, not only do you need to control the flows within your workspace, but you also need to be aware of surface runoff and potential high flows that can overwhelm your water management strategy. Planning the ESC approach early in the project is important. Using appropriate diversion techniques and stabilization measures can allow the successful construction of your creek project while protecting sensitive aquatic habitat. The vegetation planting plan is a critical component of the ESC plan, which will provide for long-term erosion protection, overall site stability and habitat enhancement at the creek site. Working in creeks and streams requires an extra level of planning and consideration when developing and implementing an ESC plan.
About the Expert Heather Amirault, P.E., is a water resources engineer at Stantec Consulting Ltd. She specializes in the areas of stream rehabilitation using natural channel design and geomorphic principles. Amirault has worked on stream restoration and erosion control projects across Canada.
Trout spawning migration in newly restored Oshawa Creek (Oshawa, Ontario)Poly sheeting and aquadams used to create a flume in Little Red River (Prince Albert, Saskatchewan)Turbidity curtain to separate the work area from river flows in the Little Red River (Prince Albert, Saskatchewan)Biodegradable erosion control blanket over channel banks and floodplain (London, Ontario)
A temporary erosion and sediment control filter device allows water to fl ow through at a controlled rate while separating and retaining sediment and pollutants.
HOW CONSTRUCTORS USE ADVANCES IN TECHNOLOGY TO SUCCEED
By Joe Moore, MS4 CECI
Since the inception of the Clean Water Act in 1972, businesses, regulators, engineers and constructors have been attempting to work in concert toward one goal: clean water. The challenges spread far and wide, and there are differing degrees of what clean water looks like. From chemical removal to proper storage and detention systems, to the separation of combined municipal sanitary and storm sewers, our construction industry has been challenged. Constructors have taken on the role of being pollutant removal superheroes. While being a constructor is tough, being a cost-conscious champion of the environment at the same time is even tougher.
In the history of construction, the evolution of a job site has only advanced in terms of detail. An increase in these details has created a more demanding workplace for constructors. In today’s world, constructors are the bond that holds together an engineer’s specification, a manufacturer’s product installation and a regulator’s rulebook. Constructors act as the interpreter of the rules. From countless specifications and installation techniques for thousands of products and product lines, a constructor’s library of knowledge is their key to success. The Clean Water Act has forced state and municipal regulation constructors to accept a new level of responsibility. Pollution control, erosion prevention and sediment control have all become key focal points.
Real-world struggles on-site often lead to creative solutions. The winning ideas are often found using experience and field observation, trial and error until they are refined into solutions that work. Constructors have been some of the best innovators to date. Thomas Edison, Nikola Tesla, Alexander Graham Bell, Benjamin Franklin, Thomas Jefferson, Henry Ford, Beulah Louise Henry, Maria Telkes, Stephanie Kwolek and Alfred Nobel were all constructors of sorts and the innovations that they brought to our world changed it forever.
To successfully resolve challenging problems at any level, one must dive into the details. In the case of sediment control, the details are minuscule and scientific. This can be an uneasy situation for constructors. The regulators and the engineers that constructors work with daily delve down to each diminutive detail to keep our water clean. Those same constructors have a natural disposition of asking the question of “why” and creating the solution of “how.” Those who can answer that question of “how” have often led the charge in innovation.
As a result, an entire stormwater industry has been created. It consists of engineers, manufacturers and constructors all racing to the challenge of finding the best solutions in pollution control. There is a laser focus on scientifically proven results, and the industry is shifting toward using these very details given to us by science and field observation to continue to innovate products that work.
Sediment is scientifically defined as matter that settles to the bottom of a liquid. This sounds fairly simple. Sediment has also been identified by regulatory agencies as the largest source of pollution in our regulated waterways. Constructors, agriculture and industry all knowingly and unknowingly participate in creating that pollution, and constructors and industry have been challenged through regulation to “clean up the act.” How do they do this?
The science of water can be simple. Does the pollutant— sediment in this instance—weigh more or less than water? Does it float, suspend or sink? What scientific theories can we use to separate sediment from water? Settling or filtration? What do we know about physics? If we slow down the water enough, does the loss of energy in the water allow sediment to accumulate? Most importantly: What tools can we as constructors use to stop the pollutant from leaving the site?
Silt Fencing A silt fence, sometimes (misleadingly) called a “filter fence,” is a temporary sediment control device used on construction sites to protect water quality in nearby streams, rivers, lakes and seas from sediment (loose soil) in stormwater runoff. Silt fences are widely used on construction sites in North America and elsewhere, due to their low cost and simple design. However, their effectiveness in controlling sediment can be limited, due to problems with poor installation, proper placement and/or inadequate maintenance.1
Like the hammer in construction, silt fence was one of the first proprietary sediment control devices to hit the market, and the scientific theory behind it was simple and consistent: slow the water down enough through a structural damming practice and the sediment will fall out of suspension as the water passes through or around, or is infiltrated or absorbed by the ground.
To constructors, engineers and scientists, this theory made sense and a star was born. Regulators and engineers had an answer, and constructors had a new sustainable way of controlling sediment from leaving their sites. Engineers began designing sites with the inclusion of silt fence. As regulators pushed for compliance, hundreds, thousands, then hundreds of thousands of lineal feet were installed. Today, hundreds of millions of lineal feet have been installed. Finally, designers, engineers, constructors and regulators had an answer to their problem, and it was quite simple.
However, in time, the innovative constructors, engineers and scientists begin to refine technology and theory in a search for better results. While silt fencing has become the most often used technology in the industry, there has become a race to the top for manufacturers to design a cost-effective solution that keys in on and eliminates some of the high-maintenance aspects of fencing mentioned in the above definition.
In time contractors have become inundated with regulatory inspections. Controlling sediment on-site has become as important as safety. Sediment control is one of the only phases of construction that has exposure to federal, state and municipal regulators. For constructors, that regulatory compliance comes with a cost and a real need for a consistent inspection process and devices and practices that they can count on.
The everyday frustrations that can come with installation and, more importantly, maintenance of these types of products is what has driven the recent push in innovation. Innovators now have the ability to openly test products using scientific theory and standardized ASTM testing practices to understand their products and their effectiveness at capturing sediment as well as other job site pollutants.
Enter: Fiber Rolls A fiber roll is a temporary sediment control device used on construction sites to protect water quality in nearby streams, rivers, lakes and seas from sediment erosion. It is made of straw, coconut fiber or similar material formed into a tubular roll.
Solving the maintenance issue equates to solving the cost issue for contractors, and in the past decade, scores of tubular devices have hit the market. Originally these devices were used as an alternative for check dams. These devices are proving to have very high sediment retention effectiveness, minimized maintenance costs and versatility, and are readily available to the contractor. Engineers and enforcement have begun the process of opening up the toolbox for constructors.
Many of these product lines vary greatly in size, shape and form, and the technology in the fill material is key to optimal performance. There are filter sock/fiber rolls that are even offering hydrocarbon removal coupled with additional filtration benefits. More so, this is all happening at a relatively low cost to traditional silt fencing programs.
There are multiple challenges in the industry partly because the technology is changing faster than regulation and specification manuals. As fiber roll technologies continue to hit the market, leading manufacturers have become reliant upon standardized testing protocols to compartmentalize product performance. Constructors, engineers and regulators have the challenge of staying on top of the science to understand the differences in fill material technologies and more importantly, results.
As the fast-paced race to the finish line progresses, standardized ASTM testing statistics are driving advances in technology. The technical aspects of capturing microscopic pollutants are being supported by data that is now available through testing. Information is being compiled and shared as the push for education and sediment control intensifies.
Fiber roll and filter sock technology have become the “nail gun” in the sediment control industry as the materials have proven to be more efficient, versatile and cost-effective. Constructors, engineers and regulators are becoming more familiar with the sediment and pollution retention benefits of filter sock technology, and the road is being paved for better results in terms of capturing and retaining sediment. As a result, we are all becoming better stewards of our environment.
About the Expert Joe Moore, MS4 CECI, is managing partner for Siltworm Inc. Moore has extensive experience working in the erosion control and construction industries.
References (1) Sprague, C.J. (1999). “Assuring the E ectiveness of Silt Fences and Other Sediment Barriers.” Proceedings of Conference 30, International Erosion Control Association, Nashville, TN. pp. 133-154.
A temporary erosion and sediment control filter device allows water to fl ow through at a controlled rate while separating and retaining sediment and pollutants.
In coastal Georgia, the use of green stormwater infrastructure (GSI) is becoming more widely accepted. Yet Georgia’s municipalities, not unlike municipalities across the United States, continue to discuss proper operations and maintenance of the practices and seek available resources to inspect and maintain them. Maintenance is critical for long-term performance and while GSI is no exception, inspection and maintenance of these practices is different than that of our more traditional solutions for stormwater management.
GSI practices are specifically designed to improve water quality and mimic the location’s predevelopment hydrology through infiltration and evapotranspiration, therefore demanding that certain features be routinely inspected and maintained to optimize performance. Despite more than 20 years of guidance for managing stormwater using these practices, coastal Georgia municipalities continue to document challenges associated with GSI maintenance. In 2018, the University of Georgia (UGA) Marine Extension and Georgia Sea Grant Stormwater Program received a Federal Water Pollution Control Act grant from the U.S. Environmental Protection Agency (EPA), administered by the Georgia Department of Natural Resources’ Environmental Protection Division, to support the development of a suite of photo-based tools and training for the inspection, operation and maintenance of GSI. While a fully functioning stormwater infrastructure system is essential to public health and safety, communities often lack the resources to determine maintenance needs and requirements for GSI practices. The tools and resources were created to ensure proper maintenance is occurring to address the range of pollutants associated with coastal nonpoint sources.
Site Assessment and Training In 2017, two summary reports were published that identified the specific practices to target and the audience that could most benefit from GSI maintenance, operations and inspection resources and guidance. The 2017 “Coastal Low Impact Development Best Management Practices Inventory” confirmed the location of 220 green infrastructure/low impact development (GI/LID) practices that manage approximately 90 million gallons of stormwater annually. This study noted that the most common GSI practices in the 11 coastal counties adjacent to the Atlantic Ocean are: permeable pavement (62 percent), bioretention (20 percent) and bioswales (9 percent). The visual assessments conducted along with this inventory also noted that approximately half of the sites needed some type of specifi c maintenance; however, three-quarters of the sites were considered to have “good” or “excellent” perceived effectiveness based on the visual assessment. Additionally, the study found that a minimum of 15 percent of the permeable pavement and bioretention sites are located on municipally-owned properties and maintained by city and county staff. This further confirmed the need for the post-construction inspection and maintenance training recommendations outlined in the 2017 “Coastal Stormwater Supplement Focus Group Recommendations Summary Document.” Recommendations in this study were also made to “target inspectors completing regular inspections and public works employees and contractors conducting maintenance.” A follow-up study conducted in 2019 found that 21 percent of survey respondents cited private landscapers and public works staff as the “audience in most need of stormwater training.”
The UGA Marine Extension and Georgia Sea Grant set out to learn more about ways to support municipal employees with resources and training. The project team, UGA Marine Extension and Georgia Sea Grant and local engineering consultant, Goodwyn Mills Cawood Inc. (GMC), began with regular meetings with a group that would become known as the Inspections and Maintenance Professionals Group (IMPFG). The IMPFG consists of three smaller subgroups based on geographic location, made up of over 40 municipal stormwater, engineering and public works professionals, as well as private industry. It was through meeting with the IMPFG that four themes regarding the developed tools emerged, including the need for resources that were representative of GSI practices in the coastal region, the connection of maintenance actions and level of service, the need for inspection and maintenance schedules, and the importance of the adaptability of the tools and their use as a mechanism for documenting the need for future maintenance action.
The IMPFG, along with recommendations from the noted studies, observed that the turnover rate within this field of municipal staff is high, particularly within public works and maintenance professionals. Many of these municipal employees have little to no prior knowledge of GSI or the importance of its function and lack the experience with inspecting and maintaining these practices properly before employment with the municipality. While maintenance and operations guidance for GSI is provided in Appendix E of the Georgia Stormwater Management Manual, Volume 2, the document is text-heavy and the condition ratings for various maintenance items are not well-defined, making the resource difficult to be used for new or inexperienced staff.
Photo-Based Tools The project team focused on the creation of photo-based tools using photos collected from various projects throughout coastal Georgia. The tools developed include four one-page, GSI practice specific fact sheets, three field inspection checklists, a six-minute informational video and a half-day training highlighting the resources developed and their use in the field. All the resources can be viewed and downloaded at https://gacoast.uga.edu/stormwater-management/. Each fact sheet includes basic context for the specified GSI practice (bioretention, permeable interlocking pavers, pervious concrete/porous asphalt and bioswales), highlights key maintenance activities and critical features to inspect, and provides references for maintenance costs. Each fact sheet visually corresponds with its field inspection checklist. At the top of each field inspection checklist are examples of the specific GSI practice in “good” condition, not requiring maintenance. The photo examples also correspond with a “good condition” rating in the Appendix E checklists. Following these examples is a series of inspection questions organized by specific practice features, such as drainage area and main treatment. These GSI practice features have characteristics that are indicative of their function and corresponding maintenance. The second page of each field inspection checklist includes a shortlist of qualitative questions and a series of photographic examples of potential issues. Each potential issue photo example also notes the corresponding inspection questions pertaining to the highlighted issue of concern. The checklist questions are designed such so that a “yes” to any inspection question indicates a future maintenance action.
The Marine Extension and Georgia Sea Grant also worked with Motion House Media to create a six-minute video highlighting permeable pavement maintenance, as well as the role of GSI in coastal Georgia. The city of Brunswick, Georgia, worked closely with the team to provide examples for the maintenance portions of the video, using the demonstrations as opportunities to discuss a variety of permeable pavement maintenance techniques.
After developing the resources, Marine Extension and Georgia Sea Grant and Goodwyn Mills Cawood offered two half-day training workshops, sharing the new GSI tools with representatives of two state agencies, five private-industry consulting firms and seven coastal National Pollutant Discharge Elimination System-permitted communities. A post-workshop survey showed 68 percent of workshop participants stated the Green Infrastructure Inspection and Maintenance Training “exceeded expectations” and 95 percent “agreed” or “strongly agreed” that within 12 months they planned to put into practice something they learned from the training. Additionally, as a result of these training events, two municipalities have included the tools as recommended resources for inspection, operations and maintenance in their GI/LID plan updates as part of their Municipal Separate Storm Sewer System (MS4) permit and two additional cities have indicated that they would be updating their GI/LID plans to reference the tools as well.
The Marine Extension and Georgia Sea Grant will continue to work with state agencies, local municipalities and private industry to improve green stormwater infrastructure literacy and provide workforce development opportunities to stormwater and maintenance professionals in the hopes that more municipalities implement GSI practices, regularly inspect them and perform the proper maintenance to maintain their function.
About the Expert Jessica T. R. Brown, P.E., is a stormwater specialist with the Marine Extension and Georgia Sea Grant in Brunswick, Ga.
A view of green stormwater infrastructure. The bioswale and surrounding pervious concrete have been properly maintained and functioning.
Permeable interlocking pavers covered in leaf litter and in need of maintenance.
I think there is one thing the entire global community agrees on: The year 2020 was a statistical outlier, one that was significantly different on so many levels. I refuse to use the word “unprecedented,” and truth be told I am secretly hoping that the linguists start a movement to remove it from our lexicon! Let us not dwell on the past but instead embrace an opportunity mindset and focus on how we can grow and be successful in 2021. We know with each new year comes lots of change and opportunities and so we must figure out how to leverage these opportunities. Begin by ensuring that your team has developed a strategic plan with input from your internal and external customers and key stakeholders. Remember, if you want to make sure everyone is on the same page you have got to create the page. Once you create a plan, make sure you execute it, manage it and make the necessary changes if needed. Everyone should understand who your core customers are (hint: they are the ones who generate the highest gross margins) and stay focused and disciplined and exercising communication rhythms that are aligned with their daily, weekly and quarterly goals. And everyone, regardless of their role, should know what the company’s critical numbers are and how their job affects them in a positive or negative manner. Educating your team around the numbers and creating a financial culture is important to your success and elevates everyone. As such, you must have the right information moving quickly throughout the company and getting into the right hands and heads. Your plan should be visible and understood by everybody in the company, not just by the leadership. All employees should be part of a daily group huddle that lasts less than 15 minutes focusing on the important tasks over the next 24 hours, performing tasks that ensure they hit the critical numbers and soliciting help with where they are stuck. The leadership team should meet weekly to review company progress and market and competitive intelligence gathered from employees, customers and trusted business partners. Each month, the leadership and managers should meet for a half to a full day to discuss big issues that may prevent the organization from reaching the current quarter’s goals. At the end of each quarter, the leadership and managers should meet off site to avoid interruptions, to see if they need to make any changes or corrections to the existing plan and discuss how they will successfully execute next quarter. While this may sound like a lot of meetings, it is not. When done right, a company should only spend between eight to ten percent of its time in strategic meetings. Companies with this kind of focus and discipline generally have twice the profi ts, higher employee and customer satisfaction and upon exiting, signifi cantly higher valuations. Be sure that you have the right people in the right seats doing the right things right. Thank you, Jim Collins, for that great alliteration and fail-proof business axiom. Collect input from employees that helps identify opportunities and obstacles, and have the right people and processes in place to leverage those opportunities and eliminate the constraints. Each leader and manager should meet weekly with at least one customer to collect feedback and then share those customer insights with the team. If you’ve done all of this good work you should be confident in knowing that your employees are focused on doing the right things, and are accountable and know whether they and the company have had a good, mediocre or poor day, week, month or quarter—and that you may have an unprecedented (oops) over the top 2021 I wish you all a safe, healthy and fantastic year.
In many of our watersheds, runoff from impervious surfaces leads to both high hydraulic loads and excess nutrients in our surface waters. We’ve found numerous ways to dampen the high flow events but removing the pollutants has proven more difficult. One option is to pass the runoff through an engineered bioretention system designed to create a number of removal mechanisms; however, these have often had disappointing efficiencies and sometimes become sources themselves. Two recent studies have suggested modifications to standard designs that can make these systems work much better.
Lopez-Ponnada et al. conducted a unique study of a rain garden experiment two years after it was installed in South Florida.1 Two cells were established adjacent to a building and received mainly roof runoff for two years before data collection. One cell used a standard infiltration design with 30 cm of sand, a 5 cm pea gravel layer and 30 cm of limestone gravel and a drainage pipe. The modified cell had a 30 cm layer of wood chips and pea gravel (1:2) below the sand layer, plus an internal water storage zone of 30 cm (upturned drainage pipe). Synthetic runoff containing different forms of nitrogen (N) and ground oak leaves (C source) were introduced at different rates and the effluent was sampled for removal rates. After 14 tests, five plants were established in the cells and the next season the same simulated events were conducted. Weighted average total N removal was about 50 percent for the standard system; however, the modified system reduced it significantly another 25 percent. The modified system also removed more ammonia-N and nitrite+nitrate N than the standard system. Dissolved organic carbon, however, was not changed by either system. Both systems had higher removal rates at the lower loading rates tested, and the authors suggested that a storage system for high flow events might enhance the effectiveness of these devices. Plants may have improved system performance, but the data did not clearly establish this effect.
When bioretention systems are also intended to provide aesthetic value through landscape plantings, it is important that the plants can survive dry periods between storms. Unfortunately, the tradeoff between high infiltration rates and plant-available soil moisture can result in high plant stress during dry periods. The e ect of alternative media in these systems on plant survival was the subject of a study in Ohio.2
Three large bioretention cells were established adjacent to a parking lot that provided runoff for the study. The conventional cell used a topsoil-sand blend (84 percent sand, 4 percent clay) mixed with compost (12 percent by volume) at a 55 cm depth on top of a 45 cm gravel drainage layer. A second cell used a proprietary mix of expanded shale, pine fines and compost, and the third had the site soil mixed with expanded shale at a 2:3 ratio, both cells with an expanded shale gravel drainage layer. For all three, the drainpipe was upturned to create a 75 cm storage zone. Nine species of ornamental plants were established in the same pattern on all cells. Parking lot runoff was evenly split between the three cells. Soil moisture and plant survival were monitored for two and a half seasons. The conventional cell plant survival rate was less than 50 percent due to high moisture stress levels that were present for more than 50 percent of the growing seasons. The expanded shale (shale heated to high temperatures) mixes held more plant-available moisture, with the soil:expanded shale mix having 22 percent mortality and the expanded shale/pine fines/compost mixture only losing 3 percent of the plants. The authors observed that all three bioretention cells performed well hydraulically, draining within 24 hours of storm events, and would be considered successful installations.
References (1) Lopez-Ponnada, E. V., T. J. Lynn, S. J. Ergas, J. R. Mihelcic. Long-term field performance of a conventional and modified bioretention system for removing dissolved nitrogen species in stormwater runoff. Water Research 170 (2020) https://doi.org/10.1016/j.watres.2019.115336
(2) Funai, J. T., and P. Kupec. 2019. Evaluation of three soil blends to improve ornamental plant performance and maintain engineering metrics in bioremediating rain gardens. Water Air Soil Pollut 230:3 https://doi.org/10.1007/s11270-018-4049-x
The oabove photos show field systems without and with plants. Photos courtesy of James Funai. The photo below shows an aerial view (left) of the soil blend study with the three bioretention cells, with the standard practice in the foreground with the dead plants.
