Sustainable Infrastructure and

Low Impact Development

ImagesNancy Givens and

Dr. Terry Wilson, WKU Center for Environmental

Education and Sustainability

DEGRADATION

Increased runoff & flooding

Groundwater and surfacewater contamination

Increased sedimentation

Decreased infiltration

Degraded vegetation

Soil loss andcompaction

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

STEWARDSHIP

Beauty

HabitatRestoration

Improved soil conditions

Cleaner air and water

Reduced potable water irrigation needs

Increased water absorptionand filtration

Objectives1. 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 DesignLand 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 PaversAlternate 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 AsphaltResembles conventional asphalt but has more airspaces 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 CisternAllow 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 BarrelsA 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 GardensA 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 GardensPromote healthy communities, provide nutritiousfood 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 PlantsPlants 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 CoverPlanting 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 LandscapingAn 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 BasinA 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 BasinA 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 BasinHolds 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 = PartnersWKU – CEES, Planning and Construction, Landscaping, WKYU-

PBSKY HfH + HfH BG WCMayor’s Office + BG Dept. Public WorksBG City SchoolsBGGreen Partnership for a Sustainable Cmmty.Bluegrass PRIDERiver Basin Coordinator + Team