CSM Best Management Practices (BMPs) & Design 1 — Questions and Answers

Question 1: What are Best Management Practices (BMPs)?

Methods to increase stormwater.
Controls to reduce pollution in stormwater (Correct answer)
Irrigation systems.
Construction materials.

Correct answer: Controls to reduce pollution in stormwater

Best Management Practices (BMPs) are techniques or structural controls designed to prevent or reduce the discharge of pollutants into stormwater runoff. Their primary goal is to minimize the environmental impact of development and human activities on water quality. By implementing BMPs, organizations can effectively manage stormwater and comply with environmental regulations.

Question 2: Why are BMPs important in site design?

To avoid water treatment.
To protect water quality and reduce runoff (Correct answer)
To expand project deadlines.
To increase sediment levels.

Correct answer: To protect water quality and reduce runoff

BMPs are crucial in site design because they are engineered to protect natural water bodies from pollution and control the volume of stormwater runoff. By integrating BMPs early in the design phase, sites can effectively manage rainfall, reduce erosion, and filter pollutants before they reach rivers, lakes, or groundwater. This proactive approach safeguards aquatic ecosystems and ensures compliance with environmental standards.

Question 3: Which BMP reduces erosion on slopes?

Storm drains.
Silt fences and erosion blankets (Correct answer)
Irrigation pipes.
Trash bins.

Correct answer: Silt fences and erosion blankets

Silt fences and erosion blankets are effective BMPs for reducing erosion on slopes. Silt fences are temporary barriers that slow down runoff, allowing sediment to settle out before leaving the site. Erosion blankets, often made of natural fibers, cover exposed soil on slopes to protect it from the impact of rain and wind, stabilizing the soil and promoting vegetation growth.

Question 4: What is the purpose of a detention basin?

To store drinking water.
To slowly release stormwater and reduce flooding (Correct answer)
To create wetlands.
To irrigate crops.

Correct answer: To slowly release stormwater and reduce flooding

The purpose of a detention basin is to temporarily store stormwater runoff during and after a storm event. It is designed to slowly release this water at a controlled rate into downstream channels or storm sewer systems. This controlled release helps to reduce peak flows, thereby mitigating the risk of flooding and erosion downstream.

Question 5: What is a vegetative BMP example?

Concrete channels.
Grassed swales and rain gardens (Correct answer)
Culverts.
Storm grates.

Correct answer: Grassed swales and rain gardens

Grassed swales and rain gardens are excellent examples of vegetative BMPs. These systems utilize plants and engineered soil media to filter pollutants, absorb stormwater, and promote infiltration into the ground. They mimic natural processes to manage runoff, enhance water quality, and often provide aesthetic and habitat benefits.

Question 6: What is infiltration used for in BMPs?

To increase surface runoff.
To allow water to enter the soil (Correct answer)
To speed up drainage into sewers.
To prevent evaporation.

Correct answer: To allow water to enter the soil

Infiltration in BMPs refers to the process where stormwater is allowed to soak into the ground, rather than running off the surface. This technique helps to replenish groundwater, reduce the volume of surface runoff, and filter out pollutants naturally through the soil layers. It is a key component of sustainable stormwater management, mimicking natural hydrological cycles.

Question 7: Why is BMP design tailored to each site?

To delay construction.
To match site-specific conditions (Correct answer)
To simplify all plans.
To reuse the same design for all sites.

Correct answer: To match site-specific conditions

BMP design is tailored to each site to ensure maximum effectiveness, as every site has unique characteristics. Factors such as soil type, topography, climate, existing vegetation, and land use significantly influence how stormwater behaves and which BMPs will perform best. Customizing designs ensures that the chosen BMPs are appropriate for the specific conditions and achieve optimal pollution control and runoff reduction.

Question 8: What is the function of a filter strip?

A plastic barrier.
Vegetated area to filter runoff (Correct answer)
A drainage pipe.
A fence around water.

Correct answer: Vegetated area to filter runoff

A filter strip is a vegetated area designed to treat sheet flow runoff from adjacent impervious surfaces or disturbed areas. Its function is to slow down the runoff, allowing suspended solids and associated pollutants to settle out, and for some infiltration to occur. The dense vegetation acts as a physical filter, improving water quality before the runoff enters a water body or drainage system.

Question 9: What is low impact development (LID)?

A high-cost stormwater method.
Natural techniques for local stormwater control (Correct answer)
A large dam project.
An underground reservoir.

Correct answer: Natural techniques for local stormwater control

Low Impact Development (LID) is an approach to stormwater management that mimics natural hydrologic processes to manage stormwater on-site. It employs a variety of natural techniques, often referred to as green infrastructure, such as rain gardens, permeable pavements, and vegetated swales. The goal of LID is to manage stormwater close to its source, reducing runoff volume and improving water quality through infiltration, filtration, and evapotranspiration.

CSM Best Management Practices (BMPs) & Design 1

What are Best Management Practices (BMPs)?