LOW-IMPACT DEVELOPMENT Opportunities for Flood Mitigation Name, title, I want to draw some clearer links between LID and its impact on flood mitigation

Houston Area Population Density Region is growing … adding 3.5 million by 2040 No surprise, just look at the map 2015 2040

Development Impacts by 2040 6 million more parking spaces 680 million sq. ft. more non-residential development 3.5 billion sq. ft. more residential development Along with population growth comes need for infrastructure, housing, retail, and other businesses 6, 680, 3.5

Development Impacts by 2040 390 Cinco Ranches 230 NRG Parking Lots To put it in perspective with a fun statistic – that is the equivalent 390 additional Cinco Ranches… 1,400,000 single family housing units 2040 3,594 housing units in Cinco Ranch (2010) 1,400,000/3,594 = 390 Cinco Ranches http://fuellingkaty.com/files/2010/01/CR_entry_lowres-2.JPG 4,725,464 ft or 894 miles linear feet of roadways … and 230 NRG parking lots. Which is one of the world’s largest parking lots (26,000 spaces) http://www.hinrgareahotel.com/wp-content/uploads/2014/02/HI-RELIANT-aerial-3.1.jpg NRG Park holds 26,000 parking spaces (26,000* 270 = 7,020,000 sf of parking; 7,020,000) 6million spaces* 270sf of parking spaces/ 7,020,000 =230NRG Park parking lots Fuellingkaty.com hinrgareahotel.com

Designing for Impact Guide Workshops Mapping Tool We wanted to think about the role of low impact development (LID) in this growth, so we created a guide called Designing for Impact to provide information and strategies for educating the public about LID functions, benefits, and solutions to overcome barriers to implementation. Guide: Made with input from regional stakeholders LID functions Benefits BMPs and solutions for overcoming obstacles to implementation Includes case studies Workshops 3 workshops for participants from public and private sectors, advocacy groups and interested citizens Mapping Tool Includes over 60 LID projects, and anyone can add to it.

Designing for Impact h-gac.com/go/LID Ghirardi Family WaterSmart Park The LID webpage can be found at www.h-gac.com/go/LID Or you can google H-GAC LID It includes Information on the Designing for Impact project and Upcoming Events Resource Documents on LID LID Photos Interactive mapping tool that highlights the locations of LID projects around the region The Regional Guide to LID

What do we know? LID mimics nature Slows Diverts Captures Mimics the natural conveyance of stormwater by redirecting it in a number of different ways that can both capture, slow and/or redirect stormwater. This reduces the chances for flooding, both on-site and downstream by reducing both the volume of water and the rate of waterflow. Design Workshop Asakura Robinson

What do we know? Swiss Army Knife, not a silver bullet Knife image created by Robert Bjurshagen from the Noun Project

What’s do we know? Swiss Army Knife, not a silver bullet Knife image created by Robert Bjurshagen from the Noun Project

LID is a Swiss Army Knife Asakura Robinson Asakura Robinson Asakura Robinson Design Workshop Our guide describes 12 distinct strategies. As a development strategy, it’s adaptable to site-specific needs Multi-purpose Jones + Carter Asakura Robinson Harris County Public Infrastructure Knife image created by Robert Bjurshagen from the Noun Project

LID is a Swiss Army Knife Reduces runoff Filters stormwater Adds aesthetics Increases value Multi-benefit Cuts costs Knife image created by Robert Bjurshagen from the Noun Project

Won’t fix everything, but is still highly useful Flood Mitigation and LID Won’t fix everything, but is still highly useful It isn’t the final answer, but it can be part of the solution. It is adaptable to the specific needs of any project. When it comes to understanding the impact of LID on stormwater runoff, there is no single definitive study, but some research has been done on some LID tools. Many variables to understand: the effectiveness of one specific LID tool will depend on the amount and speed of rainfall and the state of the soils, for example. Knife image created by Robert Bjurshagen from the Noun Project

Permeable Pavement A 1,000 sq. ft. driveway can produce more than 600 gallons of stormwater runoff in a 1-inch rainfall. Source: URS Group Inc., 2010

Permeable Pavement Permeable pavement can absorb 80-100% of rainfall Considerations: Slope of pavement Soil content below pavement Size and distribution of storm events Infiltration rate Frequency of surface cleaning Source: Center for Neighborhood Technology, 2010

Natural & Constructed Wetlands A one-acre wetland can typically store about three-acre feet of water, or one million gallons. Source: U.S. Environmental Protection Agency, 2006

Natural & Constructed Wetlands Wetlands reduce flood damage by $8,000 per acre each year. Source: The Conservation Fund

Natural & Constructed Wetlands Preserving 15% of the land area of a watershed in wetlands can reduce flooding peaks up to 60%. Source: U.S. Environmental Protection Agency, 2006

Natural & Constructed Wetlands Site Design is key Images: Design Workshop

Green Roofs Multiple studies show that green roofs can retain 40-80% of annual rainfall. Source: Center for Neighborhood Technology, 2010; Image: H-GAC

Policy Solutions Wide minimum roadway widths Narrower roadway design Curb & gutter requirements Make requirements flexible Excessive impervious cover Efficient site design Lack of incentives Incentives to lower costs and risks Source: Center for Neighborhood Technology, 2010; Image: H-GAC

Local Examples Site design: 220 acres and 660 housing units

Thank You Site design: 220 acres and 660 housing units