landquest-ventures

Environmental Science Explained

Sat, 21 Dec 2024 15:56:03 GMT

Environmental Science Explained

Environmental science is an interdisciplinary academic field that integrates physics, biology, meteorology, mathematics and geography (including ecology, chemistry, botany, zoology, mineralogy oceanography, limnology, soil science, geology and physical geography, and atmospheric science) to the study of the environment, and the solution of environmental problems. Environmental science emerged from the fields of natural history and medicine during the Enlightenment.[1] Today it provides an integrated, quantitative, and interdisciplinary approach to the study of environmental systems.

Environmental studies incorporates more of the social sciences for understanding human relationships, perceptions and policies towards the environment. Environmental engineering focuses on design and technology for improving environmental quality in every aspect Environmental scientists seek to understand the earth's physical, chemical, biological, and geological processes, and to use that knowledge to understand how issues such as alternative energy systems, pollution control and mitigation, natural resource management, and the effects of global warming and climate change influence and affect the natural systems and processes of earth. Environmental issues almost always include an interaction of physical, chemical, and biological processes. Environmental scientists bring a systems approach to the analysis of environmental problems. Key elements of an effective environmental scientist include the ability to relate space and time relationships as well as quantitative analysis.

Environmental science came alive as a substantive, active field of scientific investigation in the 1960s and 1970s driven by (a) the need for a multi-disciplinary approach to analyze complex environmental problems, (b) the arrival of substantive environmental laws requiring specific environmental protocols of investigation and (c) the growing public awareness of a need for action in addressing environmental problems. Events that spurred this development included the publication of Rachel Carson's landmark environmental book Silent Spring[3] along with major environmental issues becoming very public, such as the 1969 Santa Barbara oil spill, and the Cuyahoga River of Cleveland, Ohio, "catching fire" (also in 1969), and helped increase the visibility of environmental issues and create this new field of study. In today's world, environmental science plays a crucial role in assessing the impact of human activities on the environment, developing sustainable solutions to mitigate these impacts, and guiding policy decisions to protect natural resources and ecosystems, often integrating various scientific fields like chemistry, biology, physics, and geography to understand and address environmental challenges.

Key aspects of environmental science today include:

Climate Change Focus: A major area of research is modeling the effects of climate change and finding ways to minimize its impacts, including studying changes in weather patterns, rising sea levels, and ecosystem disruptions.
Pollution Management: Identifying and controlling sources of air, water, and soil pollution, including developing strategies to clean up contaminated sites.
Biodiversity Conservation: Studying and protecting biodiversity by analyzing the impacts of human activities on different species and ecosystems.
Sustainable Resource Management : Finding ways to use natural resources responsibly and efficiently to minimize environmental damage.
Environmental Impact Assessment: Evaluating the potential environmental effects of development projects before they are implemented.
Policy Advocacy: Providing scientific evidence to inform environmental regulations and policies at local, national, and international levels.

Some key roles of environmental scientists today:

Research and Data Analysis: Collecting and analyzing environmental data to understand current conditions and identify trends.
Environmental Consulting: Advising businesses and organizations on how to reduce their environmental impact and comply with regulations.
Public Outreach and Education: Communicating environmental issues to the public to raise awareness and promote sustainable practices.
Restoration Ecology: Developing strategies to restore degraded ecosystems.

The Environmental Impact of Hurricanes in Florida

Fri, 25 Oct 2024 01:20:56 GMT

The Environmental Impact of Hurricanes in Florida

It’s not just the people who suffer when hurricanes make landfall. Thousands of animals are killed, waterways are damaged, trees are uprooted, and the ground is eroded. As a natural part of Earth’s climate, these disasters are events that have been altering the coasts for millions of years.

The natural ecological destruction hurricanes in Florida cause is not inherently negative, and could even be comparable to some of the clutter-clearing, soil-enriching benefits of forest fires.

The difference in modern times, and the reason the environmental impacts of hurricanes are particularly negative today, is strictly due to humans.

There are all types of laws and regulations in place to ensure waste and substances that are harmful to the environment and people are properly disposed of and stored. Hurricanes don’t care about our regulations. They have no qualms about dispersing chemicals and waste byproducts among the homes, businesses and streets we all inhabit and use every day.

Natural Damage Verse Human-Related Hurricane Damages

Taking humans out of the equation, hurricanes will:
Strip tree canopies of their leaves (defoliation)
Destroy or alter animal habitats
Disrupt food availability for some species
Alter coastlines and reduces landmass

Our kneejerk reaction to animal death is understandably negative, regardless of whether the cause of those deaths is natural or manmade. Hurricane Hugo is believed to have halved the population of Puerto Rican Parrots.

Hurricane Gilbert is believed to have pushed the Cozumel Thrasher, a species of bird found exclusively on Isla Cozumel, to the brink of extinction. While both of those events seem tragic, they were natural.

Death or injury due to flooding or wind isn’t the only way hurricanes effect animals. Entire food chains can be disrupted. During a hurricane, the littlest animals and plants may get killed or have their habitats destroyed, forcing them to move. The predators that survived on the now relocated population then lose out on their food source, forcing the predators into starvation or migration.

Some plants only pollinate or germinate during specific seasons. A poorly timed hurricane has the potential to disrupt a plant species’ entire reproductive cycle for a whole year, which could have far-reaching future consequences on the viability of the species.

One estimate suggests the combined force of Hurricane Ivan, Hurricane Katrina, Hurricane Rita changed the position of shorelines by up to 100 meters. They believe those storms resulted in 73 square miles of lost coastline.

A Smithsonian report estimated the impact was far great, suggesting the four back-to-back storms may have resulted in a loss of up to 328 square miles of coastal wetlands in Louisiana.

These are all just the natural effects of a hurricane. As with wildfires, when you take humans out of the equation, natural disasters are simply a form of climatic creative destruction. It’s neither a positive nor negative event in the grand scheme of things, it’s just change.

The situation is far different when you add humans to that equation.

The Effect of Hurricanes When You Factor in People

Whenever a hurricane hits a populated area, garbage is always an issue. The possessions, homes and vehicles of every person or business in the path of hurricane-force winds and storm surge can become swept up in flooding. Storm surge flooding and wind can spread the contents over a large swath of land or water. A lot of the debris can be relatively easily picked up, but collecting some parts of the waste, such as motor oil or gasoline from flooded vehicles, can be a lot more challenging.

The environmental impact of chemicals and hazardous waste that gets washed out by hurricane flooding has the potential to dwarf the destructive impact of a flooded vehicle or two. Some of these chemicals soak into the ground, and even pose a long-term risk to the health of area residents by threatening to contaminate water tables and reservoirs.

A disturbing example of this happened during Hurricane Florence in September 2018. Some of the hurricane flooding inundated a “hog lagoon,” essentially a big pit holding pig waste, in North Carolina. All told, at least 110 hog lagoons were at risk for releasing pig waste during Hurricane Florence.

North Carolina is home to nearly 10 million pigs. Those 10 million pigs are estimated to produce 10 billion gallons of manure annually. All that waste is stored in lagoons laced with special bacteria that digests and treats the waste so it’s less environmentally harmful. When the waste gets out, it can lead to algae blooms that kill local fish on a cataclysmic scale. Hurricane Floyd in 1999 caused a similar issue. Lagoons overflowed and thousands of animals drowned.

While experts don’t have the evidence necessary to draw a definitive causal link, the fact is people living near these lagoons and hog farms have health issues and a lower life expectancy than the average American. The bacteria and pathogens in pig waste are dangerous, and roughly a million households in effected areas were forced to drink bottle water and be careful with ground water for months after the hurricanes until county water testers gave the all clear.

There’s also an economic cost in terms of crop destruction. Any food crops that were contaminated couldn’t be put on the market. Those crops weren’t even allowed to be used as feed until they passed rigorous testing protocol.

When the flood waters receded and well water was tested by the North Carolina Department of Health and Human Services, almost half of the wells tested positive for E. coli, coliform or both.

Hurricane Harvey had a similar effect in Houston, where there are significant industrial facilities and manufacturers dealing in potentially hazardous chemicals. Some of the carcinogenic and toxic industrial substances released during Harvey included benzene, butadiene and vinyl chloride. Estimates suggest more than 365 tons of dangerous chemicals were released into the water, air and land during Hurricane Harvey.

Don’t Underestimate the Often-Under-Reported Environmental Impacts of Hurricanes in Florida

The loss of lives and the destruction of homes and small businesses caused by hurricanes are certainly tragic, but they are usually measurable. The environmental impact of a hurricane can be much harder to quantify, especially when you put modern manufacturing and industrial hazardous waste into the equation.

Floridians should be cognizant of those risks and take extra steps to ensure their families are safe from those hazards if a hurricane is on the way.

Hurricanes Caused A Wide Variety of Environmental Damage in Florida

Aquatic ecosystems

Hurricanes can increase turbidity, which reduces the amount of light available to aquatic plants and can lead to declines in fish populations. Hurricanes can also cause large amounts of organic matter to flow into coastal waters, which can lead to low oxygen levels and kill aquatic species.

Mangrove forests

Loss of mangrove forests can lead to the release of carbon into the atmosphere, which can destabilize shorelines and reduce habitats for endangered species.

Beach environments

Hurricanes can erode and narrow shorelines, which can force beach-nesting and migratory birds to relocate.

Urban forests

Hurricanes can cause widespread damage to trees, including uprooting, defoliation, and limb loss. Urban forests provide many ecosystem services, including reducing pollution and flood risk.

Invasive plants and animals

Hurricanes can move invasive plants and animals to new locations. For example, Hurricane Irma uprooted plants and increased turbidity in Lake George, which led to a decline in eelgrass beds.

Toxic chemicals

Hurricanes can destroy facilities that produce energy and chemicals, and release toxic pollutants into the environment.

Crop destruction

Hurricanes can destroy food crops, which can't be sold or used as feed until they pass rigorous testing.

Barrier islands

Hurricanes can destroy foredunes on barrier islands, which can make inland areas more vulnerable to future storms.

Here’s How Climate Change Is Affecting Hurricane Season

Sun, 29 Sep 2024 00:03:38 GMT

Here’s How Climate Change Is Affecting Hurricane Season

Rising global temperatures have created the conditions for deadlier storms.

If it seems as though the most intense hurricanes happen more often than they used to, you’re right: The proportion of Atlantic Ocean hurricanes that are Category 3 or above has doubled since 1980. And if you’re wondering how climate change has contributed, consider this: Over 90% of the heat trapped by greenhouse gases has been absorbed by the world’s oceans. That means warmer waters, rising seas, higher wind speeds and more moisture in the atmosphere. These shifts are making hurricanes stronger, wetter and more likely to intensify rapidly, unleashing record-breaking downpours with little time for communities to evacuate.

“Scientists expect that the rapid intensification of hurricanes will continue in the future unless drastic measures are taken to limit further climate change.”

— Fiona Lo, Climate Scientist

Hurricane season in North America is underway. Already, the second storm of the year to earn a name, Beryl, has cut a destructive swath across the Caribbean and the United States. This year, the National Oceanic and Atmospheric Administration (NOAA) forecasted an extremely active hurricane season, anticipating between 17-25 named storms (the average is 14) and 4-7 major storms (average is 3) that reach category 3 and above with wind speeds exceeding 111 mph. Intense seasons like this are likely to be a more common occurrence in a warmer world, as higher temperatures, rising seas, and changing weather patterns create the conditions for bigger, more destructive, longer lived, and more rapidly strengthening storms. Here’s how climate change is affecting the Atlantic hurricane season:

The hotter the air, the more water it can hold. The second thing a hurricane needs to form is moisture. Water is evaporated and pulled up into the developing storm as it spins across warm waters of the tropical Atlantic. Hotter air temperatures mean more moisture can be held as vapor in the atmosphere, which allows storms to ingest greater amounts of water that will eventually condense into clouds and be released as rainfall.

Condensation also releases heat into the storm, fueling its intensification. Models estimate that human-caused global warming has increased hurricane extreme hourly rainfall rates by 11%.

ENSO fluctuations are becoming more extreme. Climate change is also contributing to larger swings between the two phases of the El Niño Southern Oscillation (ENSO)—meaning stronger versions of both El Niño or La Niña patterns. Currently, the Atlantic is headed towards a La Niña, which favors hurricane formation because it lessens vertical wind shear.

Differences in wind speeds at different heights in the atmosphere can tear a storm apart, while less shear (more consistency in wind speeds between altitudes) allows storms to stay together and build strength.

All these factors add up to more intense tropical storms in a world altered by climate change—meaning more category 3-5 storms and more big storms back-to-back. Since 1975 the number of category 4-5 cyclones has roughly doubled

This doesn’t necessarily mean that there will be more hurricanes; however, the ones that do form can be bigger and cause more damage (on top of the already estimated $2.6 trillion in damages since 1980.) If anything, data shows a slight decrease in the number of storms, moving more slowly along their path and releasing extreme wind and rain over a single location for longer periods.

Higher temperatures mean more energy to form hurricanes. To understand how hurricanes are being affected by climate change, it’s important to understand how hurricanes are formed. They are essentially clusters of thunderstorms, building strength as they sweep westward using the energy from warm tropical waters. Under the right conditions, the Earth’s rotation will cause the cluster to spin into a cyclone shape. Because heat is energy, increases in sea surface temperatures play a critical role in strengthening these storms.

The ocean is a major heat sink for the planet, absorbing over 90% of the excess heat trapped by greenhouse gasses in the Earth’s atmosphere over the past few decades.

Global sea surface temperatures have increased approximately 2.8°F since the beginning of the 20th century, and ocean heatwaves, large areas of above-normal temperatures that can last for months, are much more common and widespread.

A hotter ocean means there is more energy available to fuel tropical storms, ultimately making it a more destructive event when it hits land.

Currently, the Atlantic is headed towards a La Niña, which favors hurricane formation because it lessens vertical wind shear. Differences in wind speeds at different heights in the atmosphere can tear a storm apart, while less shear (more consistency in wind speeds between altitudes) allows storms to stay together and build strength. Tropical storms are undergoing rapid intensification more frequently.

Rising sea levels are making hurricanes more deadly. Sea level rise due to climate change has also made hurricanes a more dangerous threat for more people. As sea levels rise, coastlines are put at increased risk of flooding. Sea levels have risen roughly 8 inches since the late 19th century, and the rate of rise is accelerating as climate change worsens. When a hurricane makes landfall, water is pushed inland by high-speed winds in an event known as storm surge. Every additional inch of sea level rise allows the surge to travel farther inland, threatening a wider area and causing more damage, death, and injury. This is especially true in areas where increasing human development along the coast has exposed more people and homes to greater risk.

As temperatures continue to rise, communities along the East and Gulf coasts can expect to be hit harder by destructive storms. Despite this, more and more people are choosing to live and build near the shore, increasing the cost of damages when hurricanes strike. Slowing warming temperatures and building adaptation measures to protect coastal communities will become more urgent as Atlantic hurricanes intensify.

Storm Water Technology Fact Sheet Baffle Boxes

dan@marketing2go.biz (Cindy Dalecki) — Thu, 19 Sep 2024 20:44:01 GMT

Storm Water Technology Fact Sheet: Baffle Boxes

Baffle boxes are concrete or fiberglass structures containing a series of sediment settling chambers separated by baffles. The primary function of baffle boxes is to remove sediment, suspended particles, and associated pollutants from storm water. Baffle boxes may also contain trash screens or skimmers to capture larger materials, trash, and floatables. Baffle boxes are located either in-line or at the end of storm pipes. Figure 1 shows a typical baffle box design. The use of baffle boxes for pollutant removal is based on the concept of slowing the flow velocity through the box, thereby allowing solids and associated pollutants to settle to the bottom of the box. Storm water enters the box and begins to fill the first chamber. As water encounters the baffles, flow velocity decreases, allowing particles with a settling velocity greater than the horizontal flow velocity to settle to the bottom of the box. In addition to decreasing flow velocities, the baffles impede particle movement. As suspended solids strike the baffles they begin to settle. Larger particles usually settle out first and accumulate in the first chambers while smaller particles usually settle out in subsequent chambers.

APPLICABILITY

Baffle boxes have proven effective in removing sediment from storm water runoff. They are mainly utilized in areas where sediment control is a primary concern, while other storm water Best Management Practices (BMPs) may be more effective in areas where additional storm water pollutants, such as dissolved nutrients, oil and grease, or metals, are prevalent. Florida has used baffle boxes for several years. By 1998, Brevard County, Florida, had 42 baffle boxes serving residential areas, collecting runoff from lawns, driveways, and streets. Sediment accumulation in the baffle boxes varies greatly and depends on site characteristics such as drainage area, land use, soil type, and slope. In addition, non-wet weather flows, such as runoff from domestic activities like washing cars or watering lawns, can increase sediment contributions to storm sewers. Baffle boxes are ideally suited for retrofitting into existing storm pipes. Baffle boxes for pipes up to 48 inches in diameter can be precast, making installation quick and cost-efficient. Baffle boxes can be used for pipes up to 60 inches in diameter, but these boxes must be cast in place, making them more expensive and time-consuming to install. Baffle boxes are principally designed for sediment removal, but trash racks, screens, or skimmers can be installed to trap floatables and oil and grease as well.

ADVANTAGES AND DISADVANTAGES

Baffle boxes are simple, inexpensive storm water BMPs that effectively remove sediment and suspended solids from storm water. A primary advantage of baffle boxes is that they can be retrofitted into existing storm lines, allowing installation within existing rights-of-way. This is especially important in areas where land is unavailable or too expensive for other storm water BMPs. A major disadvantage of baffle boxes is that they require significant maintenance to remove accumulated sediment. If the boxes are not cleaned regularly, subsequent storms may resuspend the accumulated sediment and carry it out of the box, reducing the overall pollutant removal efficiency. Also, because many trash racks installed in baffle boxes are hinged at the top to prevent damage from high hydraulic pressure, they may release accumulated trash during high flows. Based on their experience with baffle boxes, officials in Brevard County recommend checking and cleaning them every two to three months during the dry season, and every month during the wet season (Bateman, et. al., 1998, and National Resources Defense Council, 1999). Another disadvantage is that baffle boxes are not designed for nutrient removal and may not be an appropriate storm water BMP if nutrients are a problem at a particular site. However, because baffle boxes effectively remove suspended materials, nutrients attached to sediments may settle out in the box. In general, modeling results show that baffle boxes are more effective at removing larger particles and less effective at removing smaller particles.

Schematic Drawing-Baffle Box

DESIGN CRITERIA

The design concept of a sediment [baffle] box is similar to the design of a three-chamber water quality inlet (also known as an oil/grit separator). Many of the earliest baffle boxes were, in effect, modified septic tanks. Typical baffle boxes are 3 to 5 meters (10 to 15 feet) long, 0.6 meters (2 feet) wider than the pipe, and 2 to 2.7 meters (6 to 8 feet) high. Weir height is usually 1 meter (3 feet). Weirs are usually set at the same level as the pipe invert to minimize hydraulic losses.

Manholes are set over each chamber to allow easy access for cleaning and maintenance. Manholes should be located within 15 feet of a paved surface to allow access by vacuum trucks for box maintenance. The design of the baffle box can be modified to promote easy cleaning and to prevent nutrient leaching from accumulated biota. Some fiberglass baffle boxes have been designed to include sliding grates on both ends. These gates are closed during cleaning to block flow, allowing removal of accumulated sediments and trash without vacuuming up incoming or residual flows. These baffle boxes also have rounded bottoms that cause accumulated sediment to collect in the middle of the box, making it easier to vacuum it out.

Baffle boxes can also be designed with aluminum screens installed below the inflow pipe but above the baffles. In this design, incoming flow drops through the screen, trapping trash, yard waste, and other debris away from the accumulating water below. Leaching is reduced because this debris is kept out of standing water. 4

Therefore, there is less chance of introducing nutrients into the outflow. Trash deflectors are set at the outflow end of the box, reducing the chance of carrying garbage out with excess flow. Preliminary modeling by the Florida Institute of Technology indicates that these screens do not become clogged even under heavy loads of debris. As flow accumulates in the first chamber, it is forced over a baffle into the next chamber. Flow deflectors at the top of the baffle reduce the possibility of sediment being carried from one chamber to the next. Flow exits through the outlet pipe.

Possible modifications to a standard baffle box design to accommodate site-specific conditions include:

• a two-chamber box for small pipes and small drainage areas;

• a three-chamber box for larger pipes; and

• two multi-chambered boxes in a series. These design modifications have not been fully studied. However, the Florida Institute of Technology used hydraulic scale-modeling to evaluate box size and shape, along with baffle size and placement, on pollutant removal efficiency. Using three, four, and five-chambered baffle boxes, this study evaluated the sediment removal efficiencies of fine and coarse-grained sediments under several typical flow rates and sediment concentrations. The researchers also evaluated the effect of changing the depth of the box and raising the height of the baffles. The results showed that, in general, adding more chambers to the box did not increase sediment removal because each chamber became shorter, and thus sediment did not settle out as efficiently. Resuspension of sediments in the box was a consistent problem because incoming flow disturbed sediments that had already settled, causing them to be resuspended and carried out of the settlement chamber.

The study suggested that reducing resuspension in the box would increase its overall efficiency, but this has not been investigated. A project to evaluate two baffle boxes in a series is underway at Sunset Park in Indiatlantic, Brevard County, Florida. This site consists of 23.8 acres of medium-density residential properties and 0.3 acres of highway. One baffle box was installed on a 24-inch pipe in 1992. Flow entered the box at a 90-degree angle relative to the length of the box and the weirs, forcing the flow to turn before entering the second chamber. This box removed approximately 8,490 pounds of sediment per year during the study period. A second baffle box was installed upstream of the original box in February 1998, with the goal of removing more sediment from the system. However, preliminary results indicate that overall sediment removal efficiencies have not increased (see Performance section below). 5

While 5,639 pounds of sediment per year are currently being removed by the upstream box, the downstream box only removes an additional 715 pounds per year. This slight increase in overall removal efficiencies indicates that the addition of a second box in a series is not a major design improvement for this system.

PERFORMANCE

Baffle boxes are an effective BMP to remove sediments from storm water. Baffle boxes have been shown to remove from 225 to 22,500 kilograms (500 to 50,000 pounds) of sediment per month, depending on the sediment load feeding into the baffle box. However, pollutant removal efficiencies (e.g., the percentage of pollutants removed by the BMP) depend on factors such as land use, drainage basin area, soil types, storm water velocities through the box, and the frequency and thoroughness of box cleaning. Limited data exists on the pollutant removal efficiencies of baffle boxes. Only one laboratory and one field evaluation are complete, while several more field tests are scheduled for the future. Results to date are discussed below. Sediment accumulation in baffle boxes varies greatly depending on the season and the amount and intensity of rainfall events. For example, Brevard County, Florida, monitored baffle boxes in the communities of Indiatlantic and Micco between 1992 and 1994. In a one-month period between August 21 and September 22, 1992, the Indiatlantic baffle box removed 2,040 kilograms (4,500 pounds) of sediment. This time of year (the summer season) is characterized by high intensity, short duration storms. However, in contrast, over a four-month period from September 1992 through January 1993 (during the winter season of lower intensity, longer duration storms), the box removed only 1,815 kilograms (4,000 pounds) of sediment. Monitoring of the baffle boxes included both water column and sediment samples. Measuring the concentration of contaminants in samples at both the inlet and outlet of the baffle box showed that the concentration of contaminants was reduced from the inflow to the outflow of the Indiatlantic box (see Table 1). Analysis of this site indicated removal rates of 71 percent Total Suspended Solids (TSS) and 38 percent phosphorous.

Analysis of BOD removal on three dates showed an average of 39 percent removals for two dates, but a 25 percent increase in BOD from inlet to outlet on a third date. Results from the Micco site baffle box were even more inconsistent, showing an increase in concentrations of some contaminants through the box. The researchers suggest that these increases may be due to inadequate cleaning and the resuspension of accumulated contaminants. Analysis of the sediments from the boxes, found that larger particles (primarily coarse, large-grained sand) were trapped in the first chamber of the baffle box, while finer particles (primarily fine organic and metals-rich sediments) settled out in subsequent chambers. In assessing these data along with removal efficiencies, the researchers concluded that 6

resuspension of sediments from the second and/or third chambers of the box could increase organic materials and metals in the outflow from the box, especially if the box had not been cleaned recently. A scale model test at the Florida Institute of Technology indicated that baffle boxes can remove up to 90 percent of coarse sediments at pipe velocities of 183 centimeters per second (6 feet per second). Removal of smaller fly ash particles is roughly 28 percent at the same velocities. The removal rate for coarse sediments remained constant even as sediment concentrations increased from 50 mg/L to 1000 mg/L. In contrast, removal efficiencies increased for finer sediments as sediment concentrations increased. This study also showed that an increase in the inflow rate decreased removal efficiencies. For coarser sediments, removal efficiencies declined slightly as the inflow rate increased, while removal rates for finer sediments decreased significantly as inflow rates increased. Thus, the pollutant removal efficiency of a baffle box may depend on both site-specific conditions and the characteristics of individual runoff events. More studies are either planned or underway to assess baffle box performance. Officials in Jacksonville, Florida, plan to monitor the performance of a baffle box installed on a 48-inch pipe as part of the city’s Storm Water Master Plan (City of Jacksonville Department of Public Works, 2000). This baffle box should be installed by early 2001, with performance monitoring beginning soon thereafter. The City of Gainesville, Florida, will also begin performance monitoring of a baffle box to gather information as part of their Storm Water Phase II program. Brevard County plans to continue monitoring the Sunset Park site, where two baffle boxes were installed in a series (

OPERATION AND MAINTENANCE

The key to the successful performance of a baffle box is regular maintenance, including routine inspection and cleaning. As sediment accumulates in the box, the chance for resuspension of accumulated material increases, and pollutant removal efficiencies can decline. Standing water that accumulates in the baffle box may become stagnant, leading to odor problems (England, 1996) and problems with mosquito breeding. It is important to establish a routine schedule to check the boxes and clean out accumulated sediment.

Boxes may accumulate anywhere from 225 to 22,500 kilograms (500 to 50,000 pounds) of material per month. The baffle boxes installed in Florida require monthly cleaning during the wet season and cleaning every two to three months during the dry season. However, maintenance schedules depend on individual site characteristics, including typical sediment loads, the size of the sewershed, flow rates, land use in the area, and the size of the box. For example, a baffle box in a small sewershed that does not receive much runoff will probably not need to be inspected as frequently as a baffle box serving a larger area. The size of the box may also impact the maintenance schedule. In general, the deeper the box, the longer it can function before needing maintenance. 7

Baffle boxes in Brevard County are cleaned by vacuum trucks on a regular schedule of two to six times per year. Originally, a private contractor performed the cleaning, but as the number of baffle boxes increased, the County determined that it was more cost effective and efficient to purchase a truck and perform the maintenance itself. Brevard County currently divides the use of one its vacuum trucks between pipe cleaning and baffle box clean out. During the wet season, the truck is scheduled primarily for baffle box maintenance; during the dry season, baffle boxes do not accumulate as much sediment and the truck is used primarily for pipe maintenance.

During a baffle box clean out, vacuum truck operators access the chambers through manholes set above each compartment. Boxes cannot be cleaned out if base flow remains in the inlet pipes. To block incoming flow, inflatable plugs or sandbags can be placed in the inflow pipe or in the manhole upstream. If the box is below the outfall level, additional plugs will be needed to prevent backflow. Residual material from baffle boxes is not considered hazardous and, therefore, its disposal is not problematic. In Brevard County, useable spoil is dried and used on road projects, while un-useable material is landfilled.

COSTS

Installation costs for most precast baffle boxes run between $20,000 and $30,000, depending on utilities that must be relocated to accommodate the box. Average costs are approximately $22,000. However, costs can be significantly higher for individual installations. For example, pre-design estimates for installation of a cast-in-place concrete baffle box for a 48-inch pipe in Jacksonville, Florida, are approximately $250,000. Because baffle boxes are usually retrofit into existing storm water sewers, costs are often independent of the size of the drainage area served. Most retrofit baffle boxes are about the same size, making capital costs about the same.

Good examples of this come from two Brevard County communities. A baffle box for the Cedar Lane community, which serves 0.9 acres, cost $25,027, while the Riverside baffle box, which serves 161 acres, cost $24,944. The major cost differences for drainage areas of different sizes usually result from an increase in maintenance frequency for boxes in larger drainage areas with increased runoff.

The average clean-out cost for a baffle box is $450. At an average of 1,925 kg/clean out, this is an approximate cost of $0.23 per kg of sediment removed. An average vacuum truck can clean two baffle boxes per day.

BMP Stormwater Wetland

Sat, 31 Aug 2024 00:08:26 GMT

BMP Stormwater Wetland

Introduction

Stormwater wetlands (or constructed wetlands) are structural post-construction stormwater controls similar to wet ponds whose design incorporates shallow zones and vegetation. As stormwater flows through the wetland, it removes pollutants through settling and biological uptake. Wetlands are among the most effective post construction stormwater controls in terms of pollutant removal while also offering aesthetic and habitat value. Stormwater wetlands are fundamentally different from natural wetland systems. They are designed specifically to treat stormwater and typically have less biodiversity than natural wetlands in terms of both plant and animal life. Several variations of stormwater wetlands exist, differing in relative amounts of dry, shallow and deepwater zones. Planners need to distinguish between using a constructed wetland for stormwater management as opposed to diverting stormwater into a natural wetland avoiding the latter. Altering the hydrology of a natural wetland can change and degrade the existing system.

Considerations

It's difficult to design stormwater controls with permanent pools. Stormwater wetlands are shallow, so large portions of them are subject to evaporation. This makes maintaining the permanent pool in wetlands more challenging than maintaining the pool of a wet pond. Additional difficulty arises when using stormwater wetlands in urban environments because of the large continuous land area they require. They will work in an urban environment if a relatively large area is available downstream of a site.

Stormwater hot spots are areas where certain land uses or related activities generate highly contaminated stormwater, with higher-than-usual pollutant concentrations. Typical examples include gas stations and industrial areas.

Wetlands can accept stormwater discharge from hot spots but, they need significant separation from groundwater. If designers use these practices to develop wildlife habitat, they should be careful to ensure that pollutants in stormwater discharge do not enter the food chain for organisms living in or near the wetland.

Stormwater Retrofit

A stormwater retrofit is a structural stormwater control that a community puts into place after development to improve water quality, protect downstream channels, reduce flooding or meet other specific objectives. When designers retrofit an entire watershed, stormwater wetlands have the advantage of providing both educational and habitat value. One disadvantage of stormwater wetlands is the difficulty of storing large amounts of stormwater without taking up a large amount of land. It is also possible to incorporate wetland elements, such as enhanced littoral zones (i.e., nearshore and shallow environments) and wetland plantings.

Siting and Design Considerations

Designers need to consider site-specific conditions: drainage area, slope, soils/topography and groundwater and incorporate design features that improve the longevity and performance, minimizing maintenance needs.

Drainage Area

A stormwater wetland needs enough drainage area to maintain a permanent pool. In humid regions, the drainage area needed is typically about 5 to 25 acres, but regions with less rainfall may need a larger area. In some instances, such as in areas with high water tables or regularly high rainfall, smaller systems can be feasible. However, they generally should undergo thorough hydrologic analysis to show that the practice will be viable.

Slope

Sites with an upstream slope of up to about 15 percent can use stormwater wetlands. However, the local slope should be relatively shallow to maintain permanent pool volumes. Construction on steeper slopes is possible through use of a step-pool system.

Soils/Topography

Almost all soils and geology can support stormwater wetlands, with minor design adjustments for regions of karst (i.e., limestone) topography. Designers can include liners for soils with high infiltration rates if water loss is a concern.

Groundwater

Similar to natural wetlands, constructed wetlands often have direct contact with shallow groundwater tables, unless hot spots or excessive infiltration concerns necessitate preventing such contact. This contact generally minimizes infiltration losses and maintains saturation during periods of low rainfall. In extreme cases where groundwater inflow is large relative to surface water area, the shorter detention time can reduce pollutant removal. Groundwater infiltration can decrease the temperature of the water flowing through the wetland, thereby reducing the biological activity that contributes to pollutant removal.

However, groundwater flows are typically small, and the benefit to wetland hydrology is far greater than any reductions in pollutant removal efficiency.

Design Considerations

Specific designs may vary considerably, depending on site constraints or the preferences of the designer or community. Most constructed wetlands, however, should incorporate certain design features. These fall into five basic categories: pretreatment, treatment, conveyance, maintenance reduction and landscaping.

Pretreatment

Pretreatment features remove coarse sediment particles by settling. By removing these particles from stormwater before they reach the treatment area, pretreatment reduces the maintenance burden of the wetland. A wetland typically pretreats using a sediment forebay: a small pool, usually about 10 percent of the volume of the permanent pool. Coarse particles stay trapped in the forebay, and crews perform maintenance on this smaller pool, eliminating the need to dredge and replant the entire treatment area.

Treatment

Treatment The treatment area, or permanent pool, helps a stormwater wetland remove pollutants by increasing the detention time of stormwater within the wetland. Some typical design features include the following: ν The surface area of stormwater wetlands should make up at least 1 percent of the area draining to the practice. ν Wetlands should have a length-to-width ratio of at least 1.5:1. Making the wetland longer than it is wide ensures that water entering the wetland receives adequate treatment. ν An effective wetland design displays “complex microtopography”—underwater earth berms creating both very shallow (<6 inches) and moderately shallow (<18 inches) water zones. This design provides a longer flow path through the wetland that encourages settling and biological pollutant removal processes. It also promotes greater biological diversity, allowing a range of microbial and vegetation communities to flourish, which tends to increase both health and pollutant removal performance.

intermittent flooding/drying cycles can promote mosquito breeding through predator reduction (e.g., mosquitofish, insects and amphibians) during cycles. Designs that incorporate a permanent pool and more stable hydrologic conditions are better able to maintain these predator communities, as well as more biological diversity in general, which helps promote better wetland health and function. Conveyance A stormwater wetland should convey stormwater safely and in a manner that minimizes erosion potential. Designers should always stabilize the wetland’s outfall to prevent scour as well as possibly providing an emergency spillway to safely convey water from large storms. Where thermal pollution is a concern, designers should provide shade around the channel at the wetland outlet.

Maintenance

One potential maintenance concern in wetlands is clogging of the outlet. A wetland should have a non-clogging outlet such as a reverse-slope pipe or a weir outlet with a trash rack. A reverse-slope pipe draws from below the permanent pool, extending in a reverse angle up to the riser, and establishes the water elevation of the permanent pool.

Because these outlets draw water from below the permanent pool, floating debris is less likely to clog them. In addition, no orifice should be narrower than 3 inches, smaller orifices are susceptible to clogging. Another feature that can help reduce the potential for clogging is a small pool, or “micropool,” at the outlet. (Note that these pools can become mosquito breeding grounds and nuisances if in populated areas such as neighborhoods or community parks.) Designers should also incorporate features that ease maintenance of both the forebay and the main treatment area of the wetland. Wetlands should have maintenance access to the forebay, and the treatment area should have a drain to draw down the water for the more infrequent dredging or vegetation harvesting.

Landscaping

Landscaping is an integral part of wetland design—of beautifying wetlands, making them an asset to a community, and enhancing their pollutant removal. To ensure the establishment and survival of wetland plants, a landscaping plan should provide detailed information about the selected plants, a timeline of when they will be planted, and a strategy for maintaining them. The landscape plan should also detail all plants used from within the water all the way up to the upland area.

Establishing plants in the stormwater wetland is key. The most effective techniques include using nursery stock as dormant rhizomes, live potted plants and bare rootstock. Designers can use a “wetland mulch” soil from a natural wetland or a designed “wetland mix” to supplement wetland plantings or establish wetland vegetation. Wetland mulch carries the seed bank from the original wetland and can help enhance diversity. The least expensive option is to allow the wetland to colonize itself, but this takes time and creates the potential for invasive species colonization. When developing a plan for wetland planting, designers and construction staff need to take care to establish plants at the proper depth and during the planting season. The planting season varies regionally and is generally between 2 and 3 months long in the spring to early summer. Plant lists are available for various regions of the United States through wetland nurseries, extension services and conservation districts. Designers should use native plants wherever possible.

Design Variations

Wetland designs can vary in terms of volume of the wetland in the deep pool, high marsh and low marsh, and in whether the design allows for detention of small storms above the wetland surface. Other design variations help to make wetland designs practical in cold climates. Shallow Wetland In the shallow wetland design, most of the volume is in the relatively shallow high marsh or low marsh depths. The only deep portions of the shallow wetland design are the forebay and micropool. This design generally requires less excavation and lower costs, and it is very effective at maximizing vegetation cover. Because the pool is very shallow, though, this design typically needs a large amount of land to store the water quality volume (i.e., the volume of stormwater the wetland will treat). Also, this system type may not be suitable where thermal impacts to cold water streams are a concern.

Extended Detention Wetland

The extended detention wetland design is the same as the shallow wetland, with additional storage above the marsh surface. Stormwater stays in this extended detention zone for between 12 and 24 hours.

This design can treat a greater volume of stormwater in a smaller space than the shallow wetland design. When choosing it, designers should select plants that can tolerate wet and dry periods for the extended detention zone.

Pond/Wetland System

The pond/wetland system combines the wet pond (see Wet Ponds fact sheet) design with a shallow marsh. Stormwater flows through the wet pond and into the shallow marsh. Like the extended detention wetland, this design needs less surface area than the shallow marsh because it stores some water in the relatively deep (i.e., 6 to 8 feet) pond. Pocket Wetland In this design, the bottom of the wetland intersects with the groundwater, which helps to maintain the permanent pool. This option is helpful when the drainage area is not large enough to maintain a permanent pool. Subsurface Flow Wetlands In the subsurface flow wetland design, stormwater flows through a rock or gravel filter (also known as the medium) with wetland plants at the surface. Biological activity and pollutant uptake by plants removes the pollutants. This practice is fundamentally different from other wetland designs because subsurface wetlands are more similar to filtering systems, while most wetland designs behave like wet ponds with differences in grading and landscaping. With a surface layer of mulch for insulation, sub-surface wetlands are also better suited to cold climates where freezing is a concern.

Stormwater Reuse Wetland

Stormwater can be a valuable water resource, helping to offset the use of potable water in water-scarce regions. Stormwater wetlands can harvest and partially treat stormwater for non-potable uses such as irrigation. In this case, designers should perform a water balance analysis to account for the water that users will take from the wetland and make sure the wetland will not dry out. When done correctly, this planned withdrawal can even improve wetland inundation characteristics and vegetation survival.

Limitations

Features of stormwater wetlands that may make designs challenging and limit their usage include the following:
Stormwater wetlands consume a relatively large amount of space.
Stormwater wetlands can become a breeding area for mosquitoes without proper design and maintenance.
Stormwater wetlands need careful design and planning to ensure that it’s vegetation survives.
Stormwater wetlands may release nutrients during the non-growing season when plants break down.
Designers need to ensure that wetlands do not harm natural wetlands or forested areas during the design phase. Maintenance Considerations Though design features can minimize their maintenance needs, wetlands still need regular maintenance and inspection.

Regular maintenance activities for wetlands:

Activity Schedule

Inspect vegetation during establishment or restoration. Biweekly

Until vegetation is established Inspect all components for cracking,

subsidence, spalling, erosion and sedimentation and repair as necessary. Annually

Inspect components that receive or trap debris, and clean/remove debris. Semiannually

Inspect vegetated areas for erosion, scour and unwanted growth. Annually

Replace wetland vegetation to maintain at least 50% surface area coverage

in wetland plants after the second growing season. As needed

Inspect wetland for invasive vegetation and remove where possible. Semiannually

Mow side slopes. 3 to 4 times/year Harvest wetland plants that sediment

buildup has “choked out.” Annually (as needed)

Remove sediment from the forebay when the wetland has lost 50% of its

total forebay capacity. As needed

Monitor sediment accumulations and remove sediment when it has

reduced the pool volume by 50%, when it has “choked” the plants, or

when the wetland has become eutrophic. As needed

Effectiveness

Structural stormwater management, in general, is a way to pursue four broad resource protection goals: flood control, channel protection, groundwater recharge and pollutant removal. Stormwater wetlands can meet all four of these goals, as described below.

Flood Control

One objective of stormwater controls can be to reduce the flood hazard associated with large storms by reducing peak flow from these storms. Designers can easily design a wetland for flood control by providing flood storage above the level of the permanent pool.

Channel Protection

One result of urbanization is the landscape/geomorphic changes—such as eroded stream channels—that occur in response to modified hydrology. Traditionally, stormwater wetlands have provided control of the 2-year storm for channel protection. However, it appears that this control has been relatively ineffective for channel protection, and research suggests that control of a smaller storm, such as the 1-year storm, might be more appropriate. Most current regulations therefore require that channel protection features provide control of the 1-year storm event.

Groundwater Recharge

Stormwater wetlands can only provide groundwater recharge in limited cases, and in soils with high infiltration rates. Generally, the buildup of debris at the bottom of the wetland limits infiltration rates.

Pollutant Removal

Stormwater wetlands are among the most effective stormwater controls for pollutant removal. Table 2 summarizes pollutant removal data from a database of stormwater practice performance (Clary et al., 2017). Designers can also reasonably predict a stormwater wetland’s pollutant removal performance using standard design details. One widely used method, based on an analysis of hundreds of operational stormwater wetlands, is Kadlec and Wallace’s (2009) P-k-C model.

Typical pollutant removal rates of stormwater wetlands.

Pollutant Influent Concentration (Median) Effluent Concentration (Median)

Total copper (µg/L) 4.51 3.20

Total zinc (µg/L) 22.6 12.00

Total suspended solids (mg/L) 38.9 12.0

Total nitrogen (mg/L) 1.50 1.31

Nitrate (mg/L) 0.45 0.22

Total phosphorus (mg/L) 0.18 0.10

E.coli (mp number/100 mL) 780 17

Cost Considerations

Wetlands are a relatively inexpensive stormwater control. Although total costs depend on several factors, including engineering, permitting, construction and maintenance, general equations exist to provide rough estimates. Using construction costs from 84 wetlands ranging from 0.1 to 25,000 acres, Kadlec and Wallace (2009) developed the following equation:

C = 479A0.69 where: C = cost (in thousands of dollars) a = wetland area (acres)

Using this equation, construction costs (in 2019 dollars) for a 1-acre facility would be $600,000, while a 10-acre facility would cost $3 million.

It has been suggested that total initial costs (including pre-construction costs of siting, design, permitting, etc.) per acre of treated impervious surface are $27,000 for new construction and $71,000 for retrofit projects, with pre-construction costs representing 30 to 50 percent of construction costs.

Wetland design should also consider land acquisition and maintenance costs. Stormwater wetlands consume about 3 to 5 percent of the land that drains to them, which is relatively high compared to other stormwater controls. The cost of land is therefore an important consideration.

Maintenance costs for wetlands are similar to those for wet ponds, though they can be slightly higher due to routine maintenance associated with greater vegetation cover or piping infrastructure.

It has been estimated the annual cost of routine maintenance to be roughly $1,000 per acre per year for surface flow wetlands and $1,500 per acre per year for subsurface wetlands. These estimates may show bias toward larger systems. However, King and Hagan (2011) suggest annual maintenance to be around $500 per acre of impervious surface treated. Alternatively, a community can estimate the cost of the maintenance activities outlined in the maintenance section.

Stormwater wetlands typically last longer than 20 years: a community can consider its initial investment in light of this long-life span.

Floating Wetlands

Fri, 30 Aug 2024 14:01:40 GMT

Floating Wetlands

1. Introduction

Floating treatment wetlands (FTWs) are considered a best management practice (BMP) for improving water quality by filtering, consuming, or breaking down pollutants in stormwater ponds. FTWs are rafts of wetland vegetation that float on the water's surface and can be designed to support a variety of plants. They can be made from bio-based materials, or from inorganic plastic and metal. FTWs can function in bodies of water with fluctuating water levels and nutrient loads and can be designed to float above or below the water's surface.

FTWs can help protect the environment from pollutants and sediments carried by runoff from urban, industrial, and agricultural areas. They can also increase the aesthetic value and wildlife abundance of stormwater ponds and farm ponds. FTWs can be installed on existing wet ponds with a contributing drainage area of 400 acres or less.

However, their performance is affected by the size and depth of the water body, including the volume of water that passes beneath them.

FTWs also require periodic maintenance to ensure the integrity of the wetland and the health of the plants.

Figure 1. Floating Wetlands

How Do Floating Treatment Wetlands Work?

Floating treatment wetlands (FTWs) are manmade ecosystems that mimic natural wetlands. FTWs are created using floating rafts that support plants grown hydroponically. The rafts float on a wet pond water surface and can be used to improve water quality by filtering, consuming, or breaking down pollutants (e.g., nutrients, sediment, and metals) from the water (See Figure 1). FTWs may represent a relatively low cost and sustainable engineered best management practice (BMP) for reducing pollution in stormwater.

Where Can FTWs Be Used?

Three (3) major pollutant reduction mechanisms have been identified in FTWs: 1) plants directly uptake pollutants, especially nutrients, from the water as biological uptake; 2) microorganisms growing on the floating rafts and plant root systems break down and consume organic matter in the water through microbial decomposition; and 3) root systems filter out sediment and associated pollutants. These pollutant-removal mechanisms constitute a system that could be a low-cost, sustainable method for removing pollutants from stormwater.

Figure 2. Existing Research FTW

Figure 3. Additional Existing Research FTW

If it can be demonstrated that FTWs effectively remove waterborne pollutants, FTWs could be placed on most existing lakes and ponds. Many of these ponds located in urban settings are used as stormwater catchments. Examples of research FTW applications are shown in figures 2 and 3, respectively. When used in conjunction with a stormwater wet pond, FTWs are generally placed close to the shoreline at the point(s) where stormwater enters the pond either through the buffer area or through an inflow pipe. This is so they will intercept the most polluted runoff entering the system. FTWs located near the shoreline attenuate wave action and reduce undercutting and bank/ shoreline erosion.

Potential Advantages of FTWs

FTWs provide design flexibility. FTWs can be sized to fit into almost any pond or lake. FTWs enhance the pollutant-removal effectiveness of existing stormwater wet ponds and can provide a sustainable pollutant-removal system and wildlife habitat. FTWs offer resiliency. FTWs can tolerate storm-event driven water-level fluctuations as long as they are anchored to the bottom or tethered to the shoreline so they are not damaged or lost by flowing through the outlet structure of the pond. FTWs improve aesthetics and can be used to enhance the visual appeal/interest of surface water features like ponds and lakes. 4

Potential Limitations

Anchoring FTWs can be a challenge. For maximum nutrient-removal efficiency, FTWs need to be harvested or removed seasonally. Current environmental policy would likely require harvest of plant material in the fall to receive any credit for nutrient removal as a treatment. This requires a potentially significant labor effort. FTWs occupy open water surface and may block access or reduce available area for lake/pond recreational use. Minimum water depth should be no lower than three feet (four to five feet is recommended). Plants on the FTWs can root into sediments in shallow water and cause the floating rafts to be submerged when pond water level rises during storm events. Some contaminants, such as oil and herbicides, in urban runoff could damage the plants and harm microorganisms. Non-native and invasive species (plants) should not be planted on the FTWs and may need to be weeded out of the FTWs to avoid adverse effects to local ecosystems.

Performance

Evaluating the pollutant-removal performance of FTWs is difficult, in part because the pollutant-removal processes thought to be active in FTWs supplement those already taking place in wet ponds. One method commonly used to assess FTW performance is to use mesocosms, small-scale ponds (Figure 4). The performance of FTWs is an area of active research at Virginia Tech, North Carolina State University, and Clemson University in the U.S. and at several universities in China.

Figure 4. Mesocosms. 5

Expected Cost

Although research is ongoing, initial cost estimates for FTW rafts range from $1 to $24 per square foot. The lower value is for homemade FTW rafts constructed either of recycled materials or PVC pipes. The higher value represents the cost of a commercially available, proprietary FTW rafts. Costs for vegetation plugs for planting FTWs are dependent on vegetation species and source, type of FTW system (harvested or permanent), and purpose of the FTW (nutrient management, nursery production, habitat restoration, etc.). An estimation of maintenance costs can be made based on the size of the FTWs and the labor for plant harvesting or replacement, weed management, etc. If no structure repair is required, annual costs are expected to be lower than those for constructed wetlands, which is 3 to 5 percent of the estimated construction cost.

Glossary of Terms

Best management practice – For urban lands refers to any treatment practice that reduces pollution from stormwater. BMPs can be either a physical structure or a management practice. A similar but different set of BMPs are used to mitigate agricultural runoff.

Biological uptake – The process by which plants absorb nutrients for nourishment and growth.

Detention time – See residence time. Ecosystem – energy and materials cycling within a unit that include all the organisms interacting with the physical environment.

Erosion – The gradual weathering away of soil and sediment due to water and wind. Floating treatment wetlands (FTWs) – Wetlands created from plants that can grow hydroponically on water surfaces. Natural FTWs float by their own means.

Habitat – The environment where organisms, like plants, normally live.

Hydroponics – The ability of a plant to uptake nutrients directly from water, also called aquaculture. Adv. hydroponically. Inflow – The flow of water entering a BMP, in this case, a pond. 6

Invasive species – Non-native species that can cause adverse economic or ecological impacts to the environment, usually due to the tendency of these introduced species to dominate local habitats and replace native ecological communities.

Mesocosm – A model of a biological system that is used to focus on a limited number of variables. The biological system referred to in this fact sheet is a wet pond.

Microbial decomposition – The breakdown of compounds or organic matter into smaller one with the aid of microorganisms.

Nutrients – The substances that are required for growth of all biological organisms. When considering water quality, the nutrients of highest concern in stormwater are nitrogen and phosphorus because they are often limiting in downstream waters. Excessive amounts of these substances are pollution and can cause algal blooms and dead zones to occur in downstream waters.

Outflow – The flow of water exiting a BMP, in this case, a wet pond.

Outlet structure – Also known as control structure, structure that regulates water discharging, or outflow from a BMP; serves as an exit point from the BMP.

Residence time – The average time it takes water to travel through a treatment system such as a wet pond. Residence time can also be called detention time.

Sediment – The soil, rock, or biological material particles that are formed by weathering, decomposition, and erosion. In water environments, sediment is transported across a watershed via streams.

Stormwater – Water that originates from impervious surfaces during rain events, often associated with urban areas and is also called runoff.

Sustain – Enduring for a long time (see sustainable).

Sustainable – The ability of the system to endure, or sustain, and remain productive over a long time.

Watershed – A unit of land that drains to a single pour point. Boundaries are determined by water flowing from high elevations to the pour point.

A pour point is the point of exit from the watershed, or where the water would flow out of the watershed if it was turned on end. 7

Wetland – Land that has saturated or hydric soils, or specialized wetland vegetation, and is periodically saturated with water.

Wet ponds – Stormwater impoundments that have a permanent pool of water used to treat water pollution. Normally has an outlet structure to regulate flows.

Building a Resilient and Sustainable Future

Thu, 01 Apr 2021 07:19:08 GMT

Building a Resilient and Sustainable Future: Landquest Ventures at the Forefront

This term represents a concept describing how well people and/or ecosystems are prepared to recover from hazardous climate events. It is more formally defined as, “the capacity of social, economic and ecosystems to cope with a particular hazardous event or trend or disturbance.” More specifically, climate resilience can be the ability to recover from potentially devastating climate-related occurrences such as floods and droughts . Typical methods of coping with these events appropriately might include: 1) suitable responses to maintain relevant society and ecosystem function, 2) increasing climate resilience by reducing the climate vulnerability of less fortunate people and their countries. Efforts employed today to increase climate resilience generally consist of a wide a range of social, economic, technological, and political strategies. To be effective, these efforts need to be implemented at all levels of society, ranging from local community action to global treaties.

In order to encourage societies to work towards climate resiliency. Throughout the globe, politically motivated groups are mobilizing to encourage more climate resilient development. This kind of development has become the new paradigm for sustainable development influencing thought, theory, and practice across all sectors globally. Two approaches that fall under this kind of development are: 1) climate resilient infrastructure and 2) climate-smart agriculture . A third concept taking hold are climate-resilient water services . These are services that provide access to high quality drinking water during all seasons and even during extreme weather events. Going forward, national and local governments are now more swiftly adopting policies for more climate resilient economies. International frameworks such as the Paris Agreement and the Sustainable Development Goals are drivers for such initiatives.

At present, much of the work regarding climate resilience has focused on actions taken to maintain existing systems and structures. This largely relates to the capacity of social-ecological systems to sustain extreme events and the maintaining of their integrity in the face of significant external forces. The three basic capacities are absorptive, adaptive, and transformative, each of which contributes different factors regarding resilience efforts. Most importantly, this certainly includes the capacity of social-ecological systems to renew, develop, and to utilize effects of major climate events as opportunities for innovation and evolution of new pathways forward showcasing improvements and adaptation to changes.

Today the gradual building of climate resilience is becoming a highly comprehensive undertaking involving of an eclectic array of actors and agents from individuals, community organizations , corporations , governments at local, state, and national levels to international organizations . Essentially, actions that bolster climate resilience are ones that enhance the adaptive capacity of social, industrial, and environmental infrastructures that can more easily mitigate the effects of climate change. Research indicates that the strongest indicator of successful climate resilience efforts at all scales is a well-developed, existing network of social, political, economic and financial institutions that are already positioned to effectively take on the work of identifying and addressing the risks posed by climate change.

Cities , states, and nations that have already developed such networks are, as expected, to generally have far higher net incomes and gross domestic product (GDP) in the future.

Sustainability:

Sustainability is defined as meeting the needs of the present without compromising the ability of future generations to meet their own needs. While environmental sustainability refers to:

The human race in general throughout the world want the same basic things in their lives such as: 1) immediate access to clean air and water; 2) viable economic opportunities; 3) safe and healthy places to raise their kids; 4) reliable shelter; 5) lifelong learning opportunities; 6) a sense of community; and 7) having some effective say in the decisions that most affect their lives. The ideal sustainable community takes into account and addresses multiple human needs and not just one at the exclusion of all others.

Sustainability creates opportunities where people of diverse backgrounds and perspectives feel welcome and safe in a place where every group has a seat at the decision-making table, where vision and prosperity can be shared. Its shear meaning suggests a long-term perspective primarily focusing on anticipating and adapting to change in both the present and future. It's important to point out, a high functioning sustainable community successfully manages human, natural, and financial capital in order to meet current needs while ensuring that adequate resources are available for future generations. Strong communities are the foundation of a peaceful and healthy planet for humanity. However, climate change, income inequality, and social injustice appear to be the most significant existential threats to building strong, sustainable communities.

Efforts at all levels of society throughout the world are more readily adopting more sustainable living standards are the absolute key to the future. As population growth increases and available resources are trending towards decline. One of the most important aspects of sustainability is the need for collaboration. Everyone, individuals, businesses, and governments—needs to play a role in protecting our environment and way of life for this generation and those to come. The more we incorporate the three pillars of sustainable development into everything we do, the more powerful a tool sustainability becomes to improve our lives.

How Developers Stay Afloat in a Sea of Environmental Regulations

Thu, 01 Apr 2021 07:19:08 GMT

Navigating the Changing Tides: How Developers Stay Afloat in a Sea of Environmental Regulations

Real estate land development is a significant investment of time and money, and those who are undertaking these types of projects will benefit from taking all appropriate measures to secure their interests. Developing a residential community, retail location, commercial building or other types of properties can present challenges that could pose a risk for financial loss and legal complications if not effectively managed.

One important area to which developers should give appropriate consideration is environmental impact and regulations. Both commercial and residential developers must protect their financial investment while also adhering to federal environmental laws, a process that can be challenging. Before beginning a project, regardless of the type and scope, a developer will benefit from learning about common environmental concerns that he or she may have to navigate along the way.

Reasonable solutions to common concerns

The discovery of an environmental issue could compromise an entire development project, especially if the matter could impact the health and safety of workers, residents, and others.

Some of the most common challenges that real estate developers may face during the completion of a project include the following:

Air pollution — Air pollution, nuisance smells, poor waste management and other issues could contaminate the air and affect the use of the development.

Climate change — It is possible that some could raise concerns about how the project may strain the local environment, possibly even negatively contributing to climate change.

Soil contamination — A soil test could reveal compromised land, or there may be concerns that the building process itself could cause long-term problems with soil quality.

Water pollution —There may already be pollution in the water near the proposed development, or the projected use of the land may violate regulations that prevent pollution of water sources.

Natural resources —More sites these days are encountering the presence of regulatory wetlands and waters. The recent EPA Sackett ruling has drastically changed the regulatory and permitting roles of state and federal regulatory agencies.

Dealing with environment-related concerns and environmental regulations can be a major issue for developers. Non-compliance can lead to expensive fines, and knowing how to appropriately manage these issues could be critical to the success of a project.

Disputes over compliance and other matters It may be important for a developer to have experienced guidance when managing environmental regulation issues.

Compliance disputes can be costly , and they may compromise the entire project. A developer will benefit from seeking an understanding of how to confront unfair intrusions from the government, the threat of fines and other matters that could affect the quality and completion of a project.

The Vital Role of Environmental Professionals in Commercial Development

Thu, 01 Apr 2021 07:19:08 GMT

Navigating the Maze: The Vital Role of Environmental Professionals in Commercial Development

Historically the role of the environmental science consulting professional has been to evaluate, analyze, and inform interested parties of any potential harm or impact to the environment stemming from a land disturbance activity. The selected environmental science firm employs a scientist who initially conducts environmental analysis by selecting environmental factors to evaluate. An environmental analysis, or environmental screening, is a strategic tool that is employed to find all internal and external elements that may affect the proposed development’s future performance. Environmental analysis begins at the outset in the process and assists the site developer with potential influences that might provide either an opportunity or threat to project success. The environmental science professional provides the client with a forecast of the future by identifying potential threats that could prevent the developer from achieving business objectives.

The environmental consultant utilizes a process consisting of the following steps in conducting the analysis: identify potential environmental impact issues through site selection; undertake extensive desktop research through the review of existing and/or previous documentation, and mapping study; conduct site walkover (s), collect and record field data; and finally interact with regulatory personnel to asset the extent of early government involvement.

The potential for project impact on existing natural resources could quickly escalate concerns regarding the project going forward. The presence of jurisdictional wetlands, waters of the US, sensitive aquatic sites, and/or threatened/endangered species critical habitat are just a few of these concerns. The environmental professional is well trained to focus resources on making these initial assessments and further analyzing potential risk. Future permit action associated with the clean water and/or wetland protection acts from either/or the state and federal government is pre-determined here.

A second environmental area of initial concern is the presence/absence of potential hazardous materials in association with past proposed property activity. Previous land use is then analyzed by the environmental professional, typically a professional with a geological background. Federal laws CAA, CERCLA, and/or RECRA are assessed to clarify whether field samples of air, water, and/or soils.

Overall, the professional environmental scientist’s role is crucial to the overall success of the proposed development. This does not change over time. The environmental professional will most likely always play a significant role in guiding the developer and his/her team through the initial phases of determining property use viability.