2. stormwater runoff is the number one factor in the decline of urban streams and decreasing urban water quality !
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10. challenges… Urban Foresters Engineers/ Planners Now remember, you have to work together Leftover disturbed areas are not the only place for trees We can retain valuable trees that improve watershed functions We can use trees in SW practices if we design it differently We need wider streets and curbs Keep the trees in the park, we need the tax revenue Don’t worry, we’ll come back and plant trees later.
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14. Historic Approach to Stormwater Management: move water off the site as quickly as possible
15. typical stormwater pond with no trees More recent approach is to temporarily detain runoff to control peak flows – this does not reduce the volume of runoff or mimic pre-development hydrology
46. More shade means more time between repaving. 20% shade on a street improves pavement condition by 11%, which is a 60% savings for resurfacing over 30 years. Planting along local roads
54. So what’s with turf cover? fastest growing land cover in the US! Sources: MTC (1996), VASS (1998) and PTC (1989) (% of total turf cover)
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56. Trees planted on home lawns provide shade and other benefits at maturity
57. Use trees to: block winter winds, shade summer sun, accent important views, and screen private areas Residential landscapes can be functional and beautiful
60. Stormwater runoff from 8000 square feet flows downhill along the existing curb unit. Stormwater planter system reduces intensity of a 25 year storm event by 70% or more.
66. Seattle SEA Streets Seattle SEA (Street Edge Alternatives) Streets Project uses graded swales to reduce impervious cover by 11% over traditional streets. Project has decreased stormwater volume by 97 percent.
67. A concept drawing of the $800,000 street edge alternative (SEA) project shows 14-foot-wide curved street, swales, additional trees, vegetation and diagonal parking areas for cars.
74. alternative sidewalk design Traditional sidewalk designs utilize individual tree pits (left) which confine roots; alternative designs cluster trees (right), which allows them to share rooting space. This reduces the need for tree roots to grow under pavement.