the Scope of project and LID

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Sustainable
Infrastructure and
Low Impact
Development
Images
Nancy Givens and
Dr. Terry Wilson, WKU
Center for Environmental
Education and Sustainability
DEGRADATION
Increased runoff & flooding
STEWARDSHIP
Groundwater and surface
water contamination
Increased sedimentation
Decreased infiltration
Degraded vegetation
Soil loss and
compaction
Increased
Irrigation
needs
Degradation vs.
Stewardship:
Effective land
management
practices can preserve
and restore
ecosystems, promote
water and air quality,
and contribute to
human and other
species well-being
Beauty
Habitat
Restoration
Improved soil
conditions
Cleaner air and water
Reduced potable water
irrigation needs
Increased water absorption
and filtration
Objectives
1. Create an integrated green infrastructure
model that retains, filters, and reuses all
stormwater on the site
2. Provide professional training and community
education on NPS pollution + LID techniques
3. Involve residents and the community in
project + shared stewardship of environment
4. Seek building policy revisions for KyHfH
Notable Features
Amphitheater
Walking trails / connection with Greenways
Green infrastructure + Green housing
Community Center
Housing and access roads restricted to perimeter
Rain gardens, community gardens, edible landscaping
Educational programming
Shared functions: bike swap, car sharing program
Low Impact Development (LID)
Techniques
• Conservation design
• Permeable Pavers and Asphalt
• Underground cisterns, rain barrels, and
piping
• Rain gardens and community gardens
• Native plants, edible plants, and tree cover
• Sedimentation basin, retention and
detention basins
BMP: Conservation Design
Land use development that allows sustainable
development while preserving the natural features and creating a
park like environment for residents.
Benefits: Preserves open space and vista, creates or protects
habitat for wildlife, creates natural spaces for recreation and
reflection; puts people in communities in contact with nature.
Design & Siting Considerations:
• Unique, scenic or significant natural features are preserved
• Homes and lots are laid out to maximize visual and physical
access to the natural spaces
• Homes are clustered to maximize open space (up to 50%)
Cost Considerations:
• When well-designed, generally not higher cost then
traditional developments
BMP: Permeable Pavers
Alternate paving systems that integrates
stormwater management with an aesthetic amenity on the site
Benefits: Slows stormwater; reduces runoff volume; permits
infiltration into ground; resources groundwater
Design & Siting Considerations:
• Best suited to low traffic, low speed areas
• Avoid in high pollution areas since direct filtration is uses
• Pavers hold up well to freeze/thaw cycles
Cost Considerations:
• Initial costs may exceed traditional paving materials, but
long-term maintenance are less over the 25-year life cycle
• Costs offset by reduced amount of stormwater structures
and land to manage stormwater that is needed
BMP: Permeable Asphalt
Resembles conventional asphalt but has more air
spaces that allow water to pass and into an underlying stone
reservoir that stores the surface runoff.
Benefits: Reduces stormwater runoff volume and peak discharge rates;
allows water to infiltrate into the ground; reduces pollutant transfer
Design & Siting Considerations:
• Best suited for low to medium traffic areas
• Avoid areas with high amount of sediment or erosion
• Less prone to cracking or buckling from freezing and thawin
• Don’t use in areas with high potential for contamination
Cost Considerations:
• Initial costs may exceed traditional materials, costs may be offset
by reduced amount of stormwater structures; costs vary
depending on site size, design, piping, and soil characteristics
BMP: Underground Cistern
Allow stormwater to be treated as a resource and harvested for
reuse, reducing water demand; water collected is for non-drinking
Benefits: Capture rainwater for reuse; reduce stormwater runoff
volume and discharge rate; provide alternative source for
irrigation needs
Design & Siting Considerations:
• Designed with a filter to capture debris; pumps to facilitate
reuse; and overflow systems to convey excess rainwater
• Lifespan estimated at 20-50 years
• To maximize storage drain cistern between storm events
Cost Considerations:
• Without installation, cost can range from $250 for 200-gal. to
$5,000 for 10,000 gal. cistern. Long-term savings include
lower water usage fee.
BMP: Rain Barrels
A system to collect and store rainwater from
roofs that would otherwise be lost to runoff and diverted to storm
drains and streams; relatively simple and inexpensive to construct
Benefits: Collects and stores water from storm events during
periods of drought; provides ample and free “soft water” for
gardens; diverts water from storm drains thereby reducing runoff;
saves money and improves the environment
Design & Siting Considerations:
• Can be placed under any downspout; elevate from ground
• Drain after storm events so water can be stored at next event
• A longer hose will give more flexibility in where you water
Cost Considerations:
• Costs range from $60 to $250 for purchased, or make your
own for about $35; some are designed as art forms.
BMP: Rain Gardens
A shallow depression that biofilters stormwater
runoff rather than allowing it to flow into storm drains and surface
water where it can cause erosion, pollution, or flooding.
Benefits: Prevents erosion, pollution, flooding; filters water and
improves water quality; slows runoff rate; beautifies site
Design & Siting Considerations:
• Where soils are not permeable enough to allow water to drain
and filter properly the soil should be replaced: 60% sand, 20%
compost, 20% topsoil
• Subsurface drainage from a thick bed of gravel may be used
• Native plants are recommended because they generally don’t
require fertilizer and are drought-resistant
Cost Considerations:
• Moderate costs but high benefits
BMP: Community Gardens
Promote healthy communities, provide nutritious
food and food security especially for low income persons. Contribute to
the preservation of open space and create recreational opportunities.
Benefits: Provide nutritious food; give control over the quantity and
kind of pesticides used; increase food security; save $$; increase
community bonds; get people outside; improve health
Design & Siting Considerations:
• Plots should be ‘leased’ per season
• Some aspects can be shared, e.g., tools and equipment; watering
according to a schedule
• Soil preparation is crucial, and as you sow so you shall reap
Cost Considerations:
• Generally, a great return for the amount invested
BMP: Native Plants
Plants that evolved naturally in a particular area and
are well-suited to the soil, moisture, and weather conditions.
Their root systems help rainfall percolate into the soil; reducing
erosion and runoff. This improves water quality
Benefits: They are low-maintenance, require less water, are in
natural balance with other species and are often quite beautiful.
Design & Siting Considerations:
• Many are heat and drought tolerant
• Plant to provide habitat to butterflies, birds, and other wildlife
Cost Considerations:
• These can be planted from seed, transplanted from the wild
(if access), or purchased. Reduced water and maintenance
needs offset the purchase costs.
BMP: Tree Cover
Planting trees provides shading and can moderate
the microclimate. Trees prevent direct sunlight, reduce surface
temperature, create habitat, and have strong aesthetic appeal.
Benefits: May be the most economical and practical method to
provide shading benefits to buildings and outdoor areas; they are
inexpensive and fairly easy to plant. The main disadvantages are
they are slow-growing and require some maintenance.
Design & Siting Considerations:
• Plant where cutting solar gain does the most good
• Plant along banks to slow flow rate and increase absorption
and filtration
• Maintain properly – watering, pruning, (naturally) fertilizing
Cost Considerations:
• Generally inexpensive and easy to maintain
BMP: Edible Landscaping
An alternative to conventional landscaping that
can be just as beautiful but offers fruits and vegetables for home use.
Benefits: Enjoy fresh and flavorful home-grown foods; control the
quantity and kind of pesticides used; increase food security; save $;
get outside, interact with the world, and have fun
Design & Siting Considerations:
• Choose a variety of fruit and nut trees, berry bushes,
vegetables, herbs, and edible flowers
• Most like well-drained soil and at least 6 hours of full sunlight
• Plants will require a certain amount of attention – watering,
pruning, (naturally) fertilizing, pest-control, harvesting
• Plant to maximize the decorative garden aspects
Cost Considerations:
• Well-maintained plants and abundant yields will minimize costs
BMP: Sedimentation Basin
A controlled stormwater release structure formed by
constructing an embankment of compacted soil across a
drainageway and installing an outlet structure and pipe - detains
runoff long enough for the majority of sediment to settle.
Benefits: Effective at trapping medium and coarse-grained
particles; helps to control runoff; relatively easy to construct
Design & Siting Considerations:
• Drainage area should be at least 10 acres
• Must be cleaned regularly to maintain effectiveness
• Not particularly effective for fine silts or clay soils or for
intense rainfall events
Cost Considerations:
• Relatively inexpensive to construct; good maintenance
practices required
BMP: Retention Basin
A constructed pond that maintains a permanent pool
of water for stormwater control plus aesthetics
Benefits: Reduces stormwater runoff volume and rate; reduces
sediment, solids and metals; Improves water quality; aesthetic
and recreational benefits; provides wildlife habitat
Design & Siting Considerations:
• Drainage area should be at least 10 acres
• Cannot be placed on steep or unstable slopes
• Should have a sediment forebay and proper depth
• Proper lining is required
Cost Considerations:
• Costs vary due to value of land, size, and complexity of
basin design
BMP: Detention Basin
Holds stormwater and then slowly releases it to
the receiving stream after a storm event.
Benefits: Effective in controlling peak stormwater discharge rates
and therefore downstream flooding; some water quality control
Design & Siting Considerations:
• Drainage area should be at least 10 acres
• Should be designed to properly drain so no standing water
• Approval may be needed by dam safety authorities
• Fencing may be needed
Cost Considerations:
• A low-cost BMP for water quality control. Cost will vary
depending on the value of the land, location, size, and design
Strength of Project = Partners
WKU – CEES, Planning and Construction, Landscaping, WKYUPBS
KY HfH + HfH BG WC
Mayor’s Office + BG Dept. Public Works
BG City Schools
BGGreen Partnership for a Sustainable Cmmty.
Bluegrass PRIDE
River Basin Coordinator + Team
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