Quiz 2 Study Guide PDF

Quiz 2 Study Guide Environmental Indicators: - Tools used to evaluate the state of the environment and signal environmental changes important to society - Comprehensive and manageable set of indicators are required to reflect societal concerns, information needs, and management st...

Quiz 2 Study Guide Environmental Indicators: - Tools used to evaluate the state of the environment and signal environmental changes important to society - Comprehensive and manageable set of indicators are required to reflect societal concerns, information needs, and management strategies - Purpose of environmental indicators - Assess the current conditions of ecosystem - Document trends over time - Anticipate early warning of degradation - Identify cause of ecosystem degradation - Demonstrate links between system components Factors Affecting the Dispersion of Road Salt: - Road type/class - Different road types (e.g., highways, residential streets) require varying amount of salt application due to differences in traffic volume and speed which can influence salt dispersion patterns - Snow clearing practices - The frequency, methods, and efficiency of snow removal (e.g., plowing and salting) determines how much salt remains on the road versus being displaced to surrounding areas - Drainage infrastructure - The design of drainage systems affects how and where road salt is carried away, potentially reaching water bodies or infiltrating into the soil - Subsurface geology - Soil type and subsurface conditions influence how salt infiltrates the ground and its potential to affect groundwater - Lawn watering - Irrigation practices near road can dissolve salt residues, accelerating the transport of chloride ions into soil and nearby water systems - Season - Seasonal conditions, such as temperature, precipitation, and snowmelt, significantly impact salt application rates and the speed of salt movement in the environment - Losses of chloride from road salt impacts freshwater ecosystems, terrestrial ecosystems, and drinking water supplies - In the USA alone, 10 to 20 million tons of road salt have been applied annually over the last 50 years - In urban setting road networks completely surrounding municipal wells - Very low attenuation potential (NaCl - Non-point source with highly variable surface loading Landscape-Based Approach to Stormwater Management: - A rationale for considering watersheds as the natural and logical boundary for environmental and land use planning - Direction regarding types of environmental studies that are required for development to take place and the range of expertise need to be involved - Evidence that Urban Design and stormwater management approaches are not sustainable over the long-term if watershed goals are to be realized and, therefore, that a change in planning and design practice is required - Enhance stormwater management within existing urban areas - Identify the diverse range of disciplines needed to effectively and successfully undertake and integrate planning and design approach - Recognition that new technologies such as the treatment train approach, low impact development (LID) principles and green building certification system (e.g., Leadership in Energy and Environmental Design - LEED, Green Globes) represent the next step in the evolution of stormwater management practice Low-Impact Development (LID): - Refers to a sustainable approach to managing stormwater that aims to mimic natural hydrological processes. It focuses on reducing runoff volume, improving water quality and enhancing groundwater recharge by promoting infiltration, evaporation, and transpiration - LID practice include techniques such as: - Green infrastructure (e.g., rain gardens, green roofs) - Permeable pavements, which allow water to infiltrate instead of running off - Rainwater harvesting, capturing runoff for reuse - Vegetated buffer strips to filter pollutants - Minimize disturbance - Minimize imperviousness - By integrating these practices, LID minimizes the environmental impacts of urbanization and reduces the strain on traditional stormwater infrastructure Treatment Train Approach: - A series of practices and approaches that meet stormwater management objectives for an area. Source (infiltration trench), conveyance (grassed swales), end-of-pipe controls (wetland/wet pond) Water Quantity and Quality Control Mechanisms: - Strategies used in stormwater management to address the volume and pollution of runoff, particularly in urban areas - Water quantity control: These mechanisms aim to manage the amount of stormwater runoff to reduce flooding and prevent erosion - Detention basins - Temporarily store runoff and release it slowly to downstream systems - Retention ponds  - Permanently hold water to control peak flows and allow infiltration - Green infrastructure - Practices like permeable pavements and rain gardens promote infiltration and reduce runoff - Water quality control: These mechanisms focus on removing pollutants from runoff before it enters natural water bodies - Sediment traps - Capture particles that carry pollutants - Bioswales and vegetated filters - Filter runoff through plants and soil - Oil-grit separators - Remove hydrocarbons and coarse debris - Combining these controls ensures better stormwater management by mitigating environmental impacts and protecting downstream ecosystems Source, Conveyance, and End-of-Pipe Controls: - Source control: These measures address stormwater at its origin, preventing or reducing runoff generating and pollutant loading - Green roofs, permeable pavements, rainwater harvesting system - Conveyance control: These mechanisms manage stormwater as it moves through the landscape, slowing, filtering, or diverting it - Bioswales, infiltration trenches, check dams - End-of-Pipe controls: These systems treat or manage stormwater before it discharges into natural water bodies - Retention ponds, wetlands, oil-grit separators - By integrating all three types of, stormwater systems can effectively reduce flooding, protect water quality, and preserve ecosystems Rainwater Harvesting: - The capture, diversion, and storage of rainwater for different uses and purposes (e.g., irrigation, drinking water, and domestic use) - The combined use of collecting the water, storing the water, and distributing the water - Not gray water or reclaimed water since it is filtered and cleaned for drinking Landscape and Drainage Considerations for BMP Selection: - Understanding and working with watersheds as the natural boundary for environmental landscape planning - Evidence that current design and stormwater management approaches are not suitable over longer periods of time. A change in planning and design practices are required - Stormwater management facilities should be fully integrated with physical, social, and ecological context - Begin at the watershed scale to achieve full range of community and environmental targets - Enhance facility performance, ensure longevity, public safety Levels of Protection: - Enhance protection: - Sensitive aquatic habitats (low pre-development erosion characteristics, habitat sensitive to siltation) - End-of-pipe storage long-term average removal of 80% suspended solids - Normal protection: - Less sensitive aquatic habitats (moderate, natural upstream sediment loads, spawning habitat less sensitive to filtration) - End-of-pipe storage long-term average removal of 70% suspended solids - Basic protection: - Areas where downstream aquatic habitat has adapted to high suspended solids loads - End-of-pipe storage long-term average removal of 60% suspended solids Stormwater Management Ponds: - Designed to manage and treat stormwater runoff - Types: - Detention ponds: temporarily store runoff and release it slowly to reduce peak flow rates - Retention ponds: permanently hold water, allowing sediments and pollutants to settle, while also providing storage for water Green Roofs: - Roof surface partially or fully filled with vegetation and growing medium, installed over a waterproof membrane. It is a sustainable stormwater management practice that provides multiple environmental and energy benefits - Components: - Vegetation layer: Plants that absorb rainfall and reduce runoff - Gowing medium: Soil or lightweight substrate to support plants - Drainage and filter layers - Waterproofing membrane: Ensures the roof remains leak proof - Benefits: - Stormwater management: Absorbs and retains rainwater, reducing runoff - Temperature regulation: Insulates buildings and reduces the urban heat island effect - Air quality improvement: Captures dust and pollutants while producing oxygen - Green roofs are effective for reducing the environmental impact of urban developing First Flush Phenomenon: - Refers to the initial portion of runoff during a rainfall event that contains and disproportionately high concentration of pollutants  - Stormwater Retrofit: - Stormwater treatment on existing development that is: - Currently untreated by and BMP - Inadequately treated by an existing BMP - Stormwater retrofits are applied along with other available watershed restoration strategies for reducing pollutants, restoring habitat, and stabilizing stream morphology as part of a holistic watershed restoration approach - Objectives: - Fix past mistakes and maintenance problems - Reduced runoff volumes to combines sewers - Reduce pollutants of concern - Support stream restoration - Comprehensive watershed restoration - Renovate the stream corridor Water Quality Control Mechanisms: - Rate reduction techniques - Techniques to mimic pre-development or natural conditions - Volume reduction techniques - Storage, infiltration - Velocity control - Evapotranspiration Water Quality Control Mechanisms: 1. Screening and filtration 2. Infiltration / groundwater recharge 3. Settling 4. Biological uptake 5. Temperature control 6. Soil adsorption Design Characteristics of Grassed Swales: - They are shallow, vegetated channels designed to convey, treat, and infiltrate stormwater runoff. They provide a natural and sustainable alternative to conventional stormwater systems like curbs and gutters