5.13 Reducing Urban Runoff

Environmental consequences of urban runoff & pollutions/ effects

-decreased infiltration (ground water recharge)

-rain washes pollutions into storm drains & into waters

Pollutions & effects:

-salt —> plant death

-sediment (turbidity)

-fertilizer (eutrophication)

-pesticides (kill non target species)

-oil & gas (kill fish)

Solution: permeable pavement

Designed to allow storm water to infiltrate & recharge ground water

-decreases runoff, pollutants carried into drains & waters

-decreases likelihood of flooding during heavy rainfall

-more costly

Solution: Rain garden

Gardens planted in urban areas, surrounding storm drain

-decreases runoff by allowing it to soak into soil

-decreases likelihood of flooding during rainfall

-creates habitat for pollinators

Solution: public transit

-more cars on the road —> more pollutants on streets to runoff (motor oil, gas)

-more cars —> more lanes & parking lots —> more runoff

-public transit (buses trains, subways) decreases urban runoff, pollution, CO2 emissions

Solution: building up not out

Decreases impervious surfaces (decreases runoff)

-can be combined with rooftop gardens which sequester CO2 and filters air pollution