Storm water management is one of the most important problems facing our cities today
Here in Portland, we have super dry summers and consistently rainy wet seasons - making it a prime location to incubate creative and effective responses to water management.
Tanner Park is an internationally recognized water management design for both people and planet - designed by the revered firm, RAMBOLL STUDIO DREISEITL, they've taken waste water and transformed it into a living, breathing park. Mimicking natural swamp systems and levarging beauty/learning:
As part of my continuing learning into this field - spreading my young wings beyond the safe and inclusive world of permaculture, I put together overview of what's plainly considered 'green infrastructure' and 'sustainable design':
- Give three examples of green infrastructure
- Community-led Food Forests: This can be variable in size; mimicking the layers of a forest, with food/fiber-producing overstory, understory, vines, shrubs, ground cover, mushrooms etc. These dense plantings (historically organized in the city by Portland Fruit Tree Project) can benefit the following: Pollinators' habitat, wildlife habitat, food for the community, learning, medicine, entertainment, micro industry, carbon sequestration, shade (inhibiting the heat growth of an urban environment), erosion control (in certain areas), and specifically water purification (allowing water to flow over these areas and be absorbed by the roots and cleaned by the roots as well).
Green Roofs: A method of populating rooftops with plants and naturally-safe materials to improve otherwise degraded and underutilized surfaces. The result can improve and benefit: wildlife, cleaner rainwater, carbon sequestration, temperature regulation (both in the city on a whole and within the given structure), provide habitat restoration, teaching opportunities, food production, pollinator promotion, and beauty.
- Rain Gardens: An element that allows either the homeowner or business-owner a way of moving excess water on their site into a beautiful and multi-functional swale. This swale is lined with either EPDM, a geosynthetic layer or gleyed with clay; adding stones and planted with sedges, rushes, grasses etc. This garden or swale has the ability of both capturing water from roofs or runoff, creating habitat and then purifying water before it makes its way back into our waterways or water table.
2. Name two reasons that investing in green infrastructure might be a be a better choice for a community than investing in or updating hard engineering, like storm sewers?
- Storm sewers play an important role in our community - however, it is an negative feedback loop - allowing sewage to pollute our rivers and expelling otherwise beneficial waste to an ‘out of sight out of mind mentality’. Green infrastructure is an important next step for investment - incorporating a closed-loop system - benefiting both people and planet. With green infrastructure such as rain gardens, infiltrating water onsite or cisterns that gather rainfall for reuse in landscape irrigation or indoor plumbing, work by capturing and treating water where it falls. Although a learning curve for civic-engagement and for fiscally responsible gov’t is with a short-term lens, green infrastructure is a tested and safe long-term investment benefiting both people and planet. With green infrastructure (community food forests, bioswales, rain gardens, green roofs) - social engagement, equity, and fewer needs for cash investment (or expensive infrastructure like fewer sewers), these systems can greatly improve life of all forms. It “...improves air quality, increases habitat and green space, enhances human health, and reduces flooding.”
4. Studies show that impervious land coverage greater than 10% degrades watershed conditions. In Portland, 49% of the land area is impervious. Name some specific ways that the impact of impervious area could be reduced?
Pervious driveways - replacing hard pack (re-using this for building material) and replacing with spaced-stone - allowing water to percolate through the surface rather than pooling up, becoming toxic and returning to our rivers.
Street Bioswales - adapting to urban street waterways and capturing at places of build-up, creating natural habitat and encouraging tree growth for passive solar mitigation.
Fewer vehicular streets! - for cars and more natural pathways (for foot traffic) in addition to trees/shrubs/habitat etc.
5. What are some ways you could incorporate stormwater into a site in an aesthetically pleasing way?
Constructing a 1200 gallon IBC tote (painted to reduce UV damage) wrapped with a wooden lattice and trained jasmine, grapes or kiwis for passive cooling in summer and warming in winter; keeping gambusia (mosquito fish); Overflow to a wildlife pond and then overflow into a drainage ditch / rain garden. Downhill side of rain garden planted with water-loving plants such as elderberry, willow, sedges, and camas. Bridge over pond for viewing and for shade/safe habitat for amphibians.
Finally, take a look at Brad Lancaster's groovy demo:
Interested in water management?
We can walk you through and design a resilient and abundant waste water program for your home or organization -