Transcript Stormwater Runnoff - University of Florida
Stormwater Runoff Define Problems Solutions Best Management Practices (BMP) Prevent Runoff Vegetative Cover -Alternative Groundcovers Reduce Pollutants -Fertilizer -Pesticides
Reduce Stormwater Runoff
Author: Rebecca McNair Edited by: Allison Steele
Hydrologic Cycle
Water on earth is constantly recycled Components of water cycle: Soil Infiltration Evaporation Transpiration- the process by which plants release water into the atmosphere Surface and channel storage Groundwater storage
The soil matrix filters and somewhat detoxifies impurities from water as it travels through the ground.
Urbanization
Intensity of land use Amount of impervious surfaces Water quality degradation
Stormwater Runoff Rainwater that flows off yards, roads and parking lots, carrying pollutants into our waterways.
Nonpoint source pollution
Sources of pollution that can not be pinpointed to any single cause. Usually associated with trash, car oil, chemical lawn products, and other residues that are easily carried away by flowing water.
According to the EPA, polluted runoff is the #1 water quality issue in Florida Nutrients Toxins Sediments Thermal Stress Debris Pathogens
Photo courtesy of NEMO
Stormwater Contaminants
Metals zinc, cadmium, copper, chromium, arsenic, lead Organic chemicals pesticides, oil, gasoline, grease Biochemical oxygen demand (BOD) Sediment Salts Nutrients grass clippings, fallen leaves, human and animal waste sand, silt, and other particles sodium chloride, calcium chloride nitrogen, phosphorus
The Problem
Increased volume of surface runoff
Increased velocity of surface runoff
Concentration of pollutants in runoff
Elevated nutrients can cause :
Polluted drinking water Excessive aquatic plant growth Lower dissolved oxygen levels Fish Kills
The Solution
Use practices or methods to prevent, reduce, retard, or remove stormwater runoff contaminants before reaching receiving waters Best Management Practices (BMP) are a series of direct recommendations based upon research, evaluation and educated assumptions
Be Florida-Friendly
Regardless of the type of property you own, you can help preserve Florida’s natural resources by:
1) 2) 3) Preventing Runoff Increasing Vegetative Cover Reducing Pollutants
Prevent Runoff
Keep rain and irrigation water on your property and out of storm drains.
Factors Affecting Stormwater Runoff:
Rainfall intensity, flow rate, season % Impervious surfaces Watershed size, slope Soil type, soil compaction Type of vegetation Density of vegetation
Within our control
Not within our control
Minimize runoff by using pervious surfaces…
for walkways, patios, and driveways
Direct downspouts and gutters towards porous areas
If downspouts drain to planted areas, be sure to select plants adapted to periodic flooding.
Collect Rain Water
Use a rain barrel or a cistern to collect and store runoff for irrigation purposes
Plan irrigation schedules according to the weather
Water during early morning hours Plants are already wet Less evaporation losses Water less frequently in cooler months Water “as needed,” not routinely Do not irrigate if rain is expected
Earth Shaping
If your property is sloped, you may want to make minor grade changes to divert runoff. This can be accomplished by:
Utilizing terraces
Terracing can be an attractive design element in your yard.
Berms and Swales
Creating swales (low areas) and berms (raised earthen areas) will help to catch, hold, and filter stormwater Elevations and depressions as small as 3-6 inches can make a huge difference
Vegetative Cover
Planting groundcovers on slopes is an excellent way to:
Catch and filter stormwater Slow the velocity of water movement Reduce erosion
Turfgrass is a versatile groundcover that is very effective at filtering nutrients.
Covering the ground with a carpet of vegetation has other advantages:
Attractive Insulates the soil Acts as a living mulch that helps to build up humus levels in the soil
Blanketflower
Gaillardia pulchella
Provides habitat and cover for beneficial insects and other predators
Disadvantages
If the ground cover is too vigorous, it may require containment It can compete with other plants for water and nutrients ‘Margarita'
The following factors should also be taken into account, when choosing the right plant for the right place…
Select plants based on site conditions:
Acid Dry alkaline- (test your soil’s pH) moist Full sun Heat shade cold Salt Space Obstructions
Periwinkle
Catharanthus roseus ‘Diva’
Alternative Groundcovers For Shade
Lilyturf
Liriope muscari
(USDA Zone 6-11) Periwinkle
Vinca major
(USDA Zone 8-11) Cast Iron Plant
Aspidistra elatior
(USDA Zone 8-11)
Alternative Groundcovers
Beach Sunflower
Helianthus debilis
(USDA Zone 8B-11) Clover
Trifolium repens
(USDA Zone 5-11) Perennial Peanut
Arachis glabrata
(USDA Zone 8-11)
Alternative Groundcovers For Sun
Asiatic Jasmine (USDA Zone 8-11)
Trachelospermum asiaticum
Junipers (USDA Zone 8-11)
Juniperus spp.
Tree Canopy
Incorporate trees in the landscape
Intercept rainfall Reduce soil compaction thus improving water infiltration into soil Increase the value of property Energy efficient way to cool the home
Reduce Pollutants
Because water can wash off our yards, it is important to reduce the amount of pollutants on our property.
Sweep grass and soil back onto lawns Sweep up any fertilizer on impervious surfaces Remove trash Clean up oil spills and leaks with cat litter Pick up after pets
It is unrealistic, and even unwise to strive for an insect, disease, and weed-free yard. Instead:
Learn to identify key pests associated with the plants in your yard Check plants regularly for signs of pest problems Determine what amount of damage warrants action
Manage Yard Pests Responsibly
Avoid routine applications of pesticides Choose the least harmful method of control Treat only affected area rather than spraying the entire yard
Fertilize Appropriately
If applied improperly, excess fertilizers can run off our yards into waterways or leach into groundwater.
Follow printed instructions carefully!
Do not apply fertilizer or pesticides before a heavy rainstorm
Further Reading
http://edis.ifas.ufl.edu
SL 143: How Contaminants Reach Groundwater PI 2: Factors Influencing Pesticide Movement to Groundwater FRE 76 Laws Governing Use and Impact of Agricultural Chemicals: Agricultural Chemicals and Water Pollution ENY 294: The Smart Way to Avoid Landscape Pests and Other Problems
Thanks for your attention!
The following presentation was made possible through a grant from FL DEP and EPA. Special thanks to the following reviewers for their valued contributions:
FL114 ELM Design Team and the FYN Subcommittee Institute of Food and Agricultural Sciences, UF Agriculture Education and Communication Department Environmental Horticulture Department Entomology and Nematology Department Soil and Water Sciences Department Florida Cooperative Extension Service in: Alachua, Broward, Clay, Hillsborough, Lake, Miami-Dade, Orange, Pinellas, Sarasota, and Volusia Counties Florida Organics Recycling Center for Excellence The Center For Wetlands, UF United States Department of Agriculture FL Department of Agriculture and Consumer Sciences: Division of Plant Industry