Low Impact Development Training Module 1: Background 1.1: Introduction

Sponsors 2 District Department of Transportation U.S. Department of Transportation Federal Highway Administration The Low Impact Development Center, Inc. University of the District of Columbia Funding for this project was provided through a grant from the Federal Highway Administration, U.S. Department of Transportation

Contributors 3 The Low Impact Development Center, Inc. John Shorb Landscaping, Inc. Logo Groundwork Anacostia River, D.C.

Copyright 4 Unless otherwise noted, Low Impact Development Training, funded by DDOT & DDOE, is licensed under a Creative Commons Attribution-NonCommerical- ShareAlike 3.0 Unported License. Content provided by cited entities remains the property of those entities and may not be used without their explicit permission.

Overview Course overview Introduction to Stormwater Basic Math Skills D.C. Stormwater Regulations 5

Motivation for this course Bioretention use is becoming widespread in the District and surrounding areas Landscaping businesses are increasingly requested to conduct maintenance of these facilities Proper maintenance requires use of specialized techniques 6

Purpose of this course To teach owners and managers of small landscaping businesses how to properly maintain bioretention cells To give owners and managers a solid background in local stormwater regulations and basic bioretention design 7

Who we are Neil Weinstein is the Executive Director of The Low Impact Development Center Dennis Chestnut is the Executive Director of Groundwork Anacostia River, DC Rasma Plato is a Landscape Designer with John Shorb Landscaping 8

Topics to be covered Mathematics for the landscape industry District stormwater regulations Bioretention design and construction Bioretention maintenance evaluation Identification and maintenance of common bioretention landscaping plants Identification and control of common invasive plants Bioretention maintenance procedures 9

Course Overview 6 weeks 12 modules, 3 hours each 9 classroom modules 3 field modules 10

Week 1 Module 1: Background –Intro to stormwater –Basic math skills –D.C. stormwater regulations Module 2: Bioretention System Design and Construction Part 1 –Design elements –Basic construction techniques –Examples –Sources –Plants and plant selection –Drainage structures and erosion control 11

Week 2 Module 3: Bioretention Systems Design and Construction Part 2 –Doing business in the District –Bioretention costs and bids –Construction Module 4: Bioretention Design Exercise 12

Week 3 Module 5.1: Safety and Equipment –Tools –OSHA requirements –District requirements Module 5.2: Bioretention Landscaping Plants –Plant identification –Plants commonly used in bioretention Module 6: In Field Construction Demonstration 13

Week 4 Module 7: Bioretention Maintenance Evaluation –Visual indicators –Corrective actions Module 8: Bioretention Maintenance Evaluation Field Visits 14

Week 5 Module 9: Maintenance Requirements –District maintenance requirements DDOT maintenance schedule –Virginia maintenance requirements –Maryland maintenance requirements Module 10: Weeds and Invasives –Plant identification review –Common weeds and invasive species –Control practices 15

Week 6 Module 11: Maintenance Practices –Routine maintenance of bioretention –Maintenance of rain barrels and cisterns –Maintenance of small permeable paver installations Module 12: Class Maintenance Demonstration 16

Intro to Stormwater Hydrologic Cycle How urbanization impacts the hydrologic cycle How stormwater can be treated to minimize these impacts 17

Expected Outcomes Be able to describe why stormwater runoff is a problem Be able to explain how low impact development reduces the damaging effects of stormwater 18

Hydrologic Cycle Diagram Courtesy of the Wisconsin Geological and Natural History Survey 19

Graphic by Livingston & McCarron, 1992 (Adapted by the California Office of Environmental Health Hazard Assessment (OEHHA)) 20

“Typical” Urbanized Coastal Area 21 Photo Courtesy of the Low Impact Development Center, Inc.

Effects of Urbanization Impervious surfaces produce higher runoff rates, volume and duration of large flows 22

How Does the Volume and Rate of Runoff Effect the Environment? Changes in land use (e.g. impervious cover, removal of natural vegetation) alter natural water flow on and below the earth’s surface. This causes: –stream bank erosion –flooding –reduced base flow in streams –degradation of stream and river habitat 23 Photo Courtesy of the Low Impact Development Center, Inc.

How Does Runoff Water Quality Effect the Environment? Runoff picks up trash, debris and pollutants: –sediment –oil and grease –fertilizers –road salts –pesticides –herbicides –pet wastes –and heat 24 Photo Courtesy of the Low Impact Development Center, Inc.

Runoff from Roads & Parking Lots Roads and parking lots] constitute as much as 70 percent of total impervious cover in ultra- urban landscapes, and as much as 80 percent of the directly connected impervious cover. Roads tend to capture and export more stormwater pollutants than other land covers in these highly impervious areas, especially in regions of the country having mostly small rainfall events. National Research Council, Urban Stormwater Management in the United States, October

Typical Pollutants Examples of Stormwater Pollutants Typical of Roads PollutantSourceEffects Trash Physical damage top aquatic animals and fish, release of poisonous substances Sediment/solidsConstruction, unpaved areasIncreased turbidity, increased transport of soil-bound pollutants, negative effects on aquatic organisms’ reproduction and function Metals Copper Zinc Lead Arsenic Vehicle brake pads Vehicle tires, motor oil Vehicle emissions and engines Vehicle emissions, brake linings, automotive fluids Toxic to aquatic organisms and can accumulate in sediments and fish tissue Organics associated with petroleum (PAHs) Vehicle emissions, automotive fluids, gas stations Toxic to aquatic organisms NutrientsVehicle emissions, atmospheric deposition Promotes eutrophication and depleted dissolved oxygen concentrations 26

Runoff from Compacted Soils Most urban soils are severely compacted, which limits their ability to infiltrate rainfall These areas become effectively impervious Runoff from compacted, bare soils carries high sediment loads 27

Stormwater’s Effect on Regional Water Quality *Source: Chesapeake Bay Program Annual loadings to the Bay: –40 million pounds of nitrogen (15% of total loading). –3 million pounds of phosphorus (16% of total) –1 billion pounds of sediment (10% of total) 28

Impacts to the Anacostia River Stormwater runoff is a principal cause of poor water quality in the Anacostia River DDOT is making a major effort to restore the Anacostia River and revitalize the waterfront 29

Conventional Stormwater Management Collect runoff in open culverts or storm sewer inlets Pipe runoff away as quickly as possible towards: –stormwater ponds –streams and rivers Creates health hazards and eyesores 30 Photo Courtesy of the Low Impact Development Center, Inc.

What is Low Impact Development? LID is a stormwater management approach with basic principles modeled after nature. The primary goal of LID is to mimic a site’s pre- development hydrology by managing runoff close to its source through: –infiltration –filtration –storage –evaporation –detention 31 Photo Courtesy of the Low Impact Development Center, Inc.

Low Impact Development LID features reduce stormwater runoff quantity and improve runoff quality by removing pollutants, therefore improving the quality of receiving streams and rivers 32 Water quality monitoring station for bioretention facility WNY Photo Courtesy of the Low Impact Development Center, Inc.

Minimize Runoff Minimize Impervious Areas Green Roofs Rainwater Harvesting 33 Photo Courtesy of the Low Impact Development Center, Inc.

Promote Infiltration Disconnect Impervious Areas Infiltration-based BMPs –Bioretention –Permeable pavement –Infiltration trenches –Infiltration basins 34 Photo Courtesy of the Low Impact Development Center, Inc.

Slow down excess runoff Disconnect impervious areas Vegetated conveyances Detention-based BMPs 35 Photo Courtesy of the Low Impact Development Center, Inc.

Cool down excess runoff BMPs that detain or retain runoff underground –Bioretention –Permeable pavement –Infiltration trenches 36 Photo Courtesy of the Low Impact Development Center, Inc.

Filter excess runoff Remove pollutants prior to discharge 37 Photo Courtesy of the Low Impact Development Center, Inc.

Chicago Alley with impermeable pavement “green alley” with permeable pavement Photos Courtesy of Chicago DOT LID Examples 38

Photos Courtesy of Seattle Public Utilities LID Examples Seattle LID Examples 39

Navy LID Examples Washington Navy Yard B-166 Parking Lot Bioretention Permeable Pavers LID Examples 40 Photos Courtesy of the Low Impact Development Center, Inc.

What is Bioretention? Bioretention is the most commonly used LID BMP It is a landscape feature that is specially designed to capture, treat, and infiltrate stormwater runoff This course is focused on the design, construction, and maintenance of bioretention 41

Typical Urban Bioretention 42 Photo Courtesy of Credit Valley Conservation (CVC) Photo Courtesy of the Low Impact Development Center, Inc.

Review Urbanization increases stormwater runoff volume and pollutant loads This causes harm to receiving waters Low impact development techniques reduce the impacts of urbanization by minimizing runoff, promoting infiltration, and removing pollutants 43

Resources USEPA’s LID Page: The LID Center: ications.htm ications.htm DDOE’s RiverSmart Homes Program: