Stormwater & South Carolina. A Case for Low Impact Development

Transcription

1 Stormwater & South Carolina A Case for Low Impact Development

2 what is stormwater?

3 stormwater & development

4 Volume of Water stormwater & development Peak Flow Urban Natural Peak Flow Rain Event Time

5 Components of Impervious Cover in the Urban Landscape Sidewalks Roads Driveways Parking Buildings Center for Watershed Protection

6 what s in stormwater? heavy metals sediments pesticides fertilizers bacteria oils

7 what s in stormwater?

8 what s in stormwater?

9 what s in stormwater?

10 what s in stormwater?

11 stormwater & south carolina rapid growth aquatic-based tourism commercial fisheries recreational fisheries swimming beaches quality of life

12 stormwater & south carolina

13 stormwater & south carolina

14 stormwater & south carolina

15 stormwater & south carolina swashes a.k.a. tidal creeks

16 stormwater & south carolina

17 stormwater & south carolina 8000 stormwater retention ponds in coastal SC

18 LID: an opportunity for south carolina vs

19 what is low impact development (LID)? source control micro-scale integrated management practices cost-effective, lot level strategies

20 common lid features pervious surfaces natural areas native landscaping natural hydrology

21 common lid aims restore, maintain, & enhance pre-development hydrology reduce runoff volume (infiltration, evaporation, use) increase runoff quality protect developing & urbanized watersheds

22 lid applications new development/ redevelopment commercial/ residential suburban/ urban

23 why lid? Quality of Life livability value sense of place aesthetics enhanced property values redevelopment potential greater marketability improved wildlife habitat thermal pollution reduction energy savings smog reduction enhanced wetlands protection decreased flooding

24 driveways parking lots sidewalks bike/walk paths emergency lanes low /slow traffic streets pervious paving

25 pervious paving

26 bioretention stormwater wetlands retention cells rain gardens swales

27 bioretention

28 bioretention

29 buffers & vegetation

30 buffers & vegetation

31 rain barrels & cisterns

32 on site stormwater management community open space narrower streets clustered housing native vegetation interconnected streets community design

33 community design

34 community design

35 community design

36 community design

37 community design

38 lid cost benefits BENEFITS FOR: builders developers business owners homeowners government community wildlife BENEFITS OVER: individual sites community scales short term long term

39 pervious paving PRODUCT MANUFACTURER COST (Sq Ft) Asphalt Various $0.50-$1.00 Geoweb Presto Products, Inc $1.00-$2.00 Grasspave TM Gravelpave TM Invisible Structures, Inc. $1.00-$2.00 Grassy TM Pavers RK Manufacturing $1.00-$2.00 Geoblock Presto Products, Inc $2.00-$3.00 Turfstone Westcon Pavers $2.00-$3.00 UNI-Eco-stone Uni-Group USA $2.00-$3.00 Checkerblock Hastings Pavement Co. $3.00-$4.00 Data from Center for Watershed Protection, Ellicott City, MD

40 COST VARIABLES regional construction costs individual contractor time of year material chosen site underlying soils size of project expected traffic life of pavement pervious paving

41 pervious paving ADDITIONAL COST BENEFITS eliminates need for other paving (curb & gutter), infrastructure, piping, etc. credits or reductions in stormwater impact / utility fees low life-cycle cost reduced over-production costs increase in available land for development

42 pervious paving w/ other lid Case study from Brunswick, NC. Bill Hunt, NCSU

43 pervious paving w/ other lid ITEM NOTES SAVINGS Pond Eliminated 3350 sf / $7 $23,450 Profit from Home & Lot $400,000 (price per recent sales) LID Costs over conventional $45,900 If 15% profit = $60,000 If 30% profit = $120,000 If 15% profit, total savings/extra revenue = $37,500 If 30% profit, total savings/extra revenue = $97,500 Case study from Brunswick, NC. Bill Hunt, NCSU

44 Is LID worth it?

45 native landscaping ACTIVITY/YEAR SUSTAINABLE LANDSCAPE (ANNUAL COST) TRADITIONAL LANDSCAPE (ANNUAL COST) Design $25,000 $25,000 0% Construction $100,000 $216,000 52% Post-Planting Management Total Up-Front Costs $16,000 $28,000 43% $141,000 $269,000 48% % DIFFERENCE SUSTAINABLE/ TRADITIONAL * Based on landscape features for a 10 acre corporate landscape, excluding site amenities such as hardscapes and aesthetic programs * Costs in 1999 US Dollars * Estimated values by Conservation Design Forum, Inc. Elmhurst, IL

46 community design savings from reduced infrastructure costs

47 roadways

48 drainage structures

49 ditches/ponds/outfalls

50 private drainage systems

51 reduced infrastructure costs: savings to builders/ developers $150/linear foot road that is shortened $25-$50/linear foot road that is narrowed $10/linear foot sidewalk that is eliminated $1,100 construction cost/parking space that is eliminated in commercial parking lot eliminated storm drains, pipes, inlets, and stormwater ponds

52 savings to builders/ developers reduced infrastructure costs reduced lot grading & clearing costs reduced landscaping installation & maintenance

53 community design

54 increased property values adjacent to recreation areas adjacent to natural areas adjacent to open areas adjacent to community areas with vegetation with mature trees

55 increased property values Homes with treed lots are 20% more saleable (Bank of America Survey of Real Estate Agents) Avg property value adjacent to greenbelt 32% greater than properties 3200 feet away (Boulder, Co) Homes 20 ft away from 4 study parks sold for $2675 more than homes 2000 ft from park (Worcester Ms) Conserving forests on residential & commercial sites enhance prop values by average 6-15% and increase rate at which units sold and leased (Morales and Weyerhaeuser) Developers in MD receiving 10-15% premiums for lots adjacent to forests and buffers (Ches. Bay Program)

56 increased property values

57 increased property values

58 increased property values

59 reduced pollutant loads into waters reduced costs for treating water savings to government reduced costs for water treatment and storage infrastructure and facilities reduced costs for retrofitting to prevent pollution reduced restoration costs reduced energy costs reduced flood damage costs reduced maintenance of infrastructure reduced service costs for residents

60 reduced energy costs savings to home/ business owners reduced maintenance costs (watering, mowing, fertilizing) reduced flood damage costs potential for reduced dependence on vehicles potential for reduced health costs (with reduced smog, enhanced air quality, etc) potential for reduced taxes (or less rate of increase) with cost savings to government

61 your bottom line vs. the triple bottom line bearable people equitable planet profit viable

62 thank Nicole Saladin ext you