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Resilient Cities Need Green Infrastructure

May 10, 2019 | Written by Mimi Burns, Jitka Dekojova, and Ken Romig

Stormwater management is an urban resilience issue - impacting water quality and the natural environment, public health and well-being, and economic development. Unpredictable storm events coupled with the climatic, physical and jurisdictional characteristics of urban areas, create extreme challenges for effective, reliable and cost-efficient stormwater management, especially in the urban Southwest. Business as usual just isn’t working. Innovative solutions are needed. It is time for a mindset change. Watershed jurisdictions need to come together and collaborate on green infrastructure solutions that treat stormwater as a resource, protect the natural environment and make urban areas more livable and vibrant.

The Challenge

The rising unpredictability of storm events presents a challenge to traditional urban stormwater management approaches, plans and systems. 100-year floods seem to happen every year and expanding urban areas are producing higher and higher runoff volumes. In the urban Southwest, where it rains infrequently, but intensely, peak stormwater volumes still need to be accommodated, compacted and hydrophobic soils that repel intense rainfall need to be mitigated, and accumulated non-source pollutants need to be captured before they contaminate nearby rivers and streams. Green infrastructure and low impact development practices are being implemented as part of forward-thinking stormwater management strategies that help cities mitigate and adapt to the inevitable shocks and stresses associated with intense storm events.

Urban flooding in Albuquerque, NM in 2013. Source: koat.com

Rain is a precious resource in the Southwest, but it can come with a vengeance, and is more often than not treated as a nuisance or a menace. Most people in the Southwest have experienced torrential rainfalls, raging arroyos, and localized flooding. This is because urban portions of our watersheds are primarily comprised of directly connected impervious areas (DCIA’s). Imagine how a drop of water moves from a roof, to a sidewalk, to a parking lot or driveway, out into the street, down into a stormwater channel or storm drain, and out into an arroyo, stream or river – bringing every bit of debris, oil and other contaminants with it. 

North Pino Channel, part of Albuquerque’s overall stormwater drainage facility, bringing stormwater underneath I-25. 

Stormwater systems rely on DCIA’s to quickly convey enormous amounts of stormwater away from developed areas, but the systems are always inflexible - lacking the ability to adapt to changes in our weather patterns without large capital investments, and frequently inadequate at treating water quality. In some cases, the federal government is stepping in with new regulations for managing polluted stormwater, like the EPA's national pollutant discharge elimination system (NPDES) general permit for municipal separate storm sewer systems (MS4) in the Middle Rio Grande watershed. This permit forces the various separate entities in the watershed to comply with water quality regulations and protections.

Green Infrastructure: Benefits and Barriers

Integration of green infrastructure (GI) and low impact development (LID) solutions into our stormwater management systems will improve community resilience and water quality. GI refers to constructed features, like parks and wetlands, that manage stormwater in part by leveraging the ecological functions of living systems. LID is a land development approach where design solutions are used to mimic natural hydrological functions. One of the main features of LID is managing stormwater runoff (i.e. infiltration, filtration, collection and reuse) as close to the source (where it lands) as possible.

Sandia Preparatory School in Albuquerque, NM uses stormwater as an amenity in the landscape design.

Both GI and LID are critical components for making our cities more resilient and adaptable to changes in storm patterns associated with climate change, and the science behind them is proven and tested. GI and LID stormwater management approaches and strategies are promoted in three evidence-based design certification programs administered by Green Business Certification, Inc.: LEED (Leadership in Energy and Environmental Design), WELL (WELL Building Standard) and SITES (Sustainable Sites Initiative). 

These approaches and strategies are often multi-functional. For example, in the desert Southwest, disconnecting urban DCIA’s and redirecting stormwater to landscaped areas including parks, medians and vegetated water quality basins can help increase urban vegetation and tree canopy, shade hot sidewalks and streets, connect citizens to nature, and create more livable, walkable cities. GI addresses not only flood control, but creates many other benefits:

  • habitat creation
  • air quality improvement
  • urban heat island mitigation
  • urban energy demand reductions
  • carbon sequestration
  • increased recreation opportunities for citizens
  • increased social engagement in outdoor areas
  • increase connection to nature
  • improved human health and wellbeing
  • potable water use reduction for irrigation
  • re-establishment of the urban forest canopy
  • decrease of cost in conventional (grey) infrastructure
  • climate resiliency

Imagine your city with a new overlay of green infrastructure.  There would be cleaner stormwater flows entering and exiting large flood control facilities. There would be reductions in the scale and frequency of localized flooding events. Large-scale stormwater facilities would be turned into stormwater amenities. And new large-scale stormwater facilities might be downsized and cost less.  

A large-scale stormwater detention pond in Gene Howe Park, Amarillo, TX. 

So why isn’t this happening everywhere? There are both real and perceived barriers to implementing LID/GI on both small and large-scale projects in urban areas – but none are insurmountable.

  • Institutional Barriers: multiple jurisdictions in the watershed; not one governing entity; lack of cooperation between different agencies; inconsistency in hydrological models used across governing entities and agencies; current development standards indirectly preventing implementation
  • Financial Barriers: increased capital development costs to make streets, parks, and stormwater facilities multi-functional;  increased maintenance costs for multi-functional facilities;  lack of incentives to encourage implementation
  • Social Barriers: lack of political will; fear and negative perception of flood waters
  • Knowledge Barriers: lack of consensus on appropriate technical standards; lack of consensus on hydrologic attenuation modeling for arid urban conditions; lack of performance data for local projects and their contributions to the larger flood control system; and lack of cost benefit analyses for various LID/GI solutions
  • Climate/Geographic Barriers: high intensity storm events; low infiltration capacity of compacted soils; low natural absorptive capacity of native soils; high volume of rapid runoff

The Rio Grande in Albuquerque, NM - the recipient of urban stormwater

I Want to Live in a Resilient City

We all want to live in a resilient city - where our friends and families, schools and businesses can continue to grow and thrive despite unpredictable weather and other stresses and shocks that are part of modern life. By integrating evidence-based green infrastructure solutions into our comprehensive, long-term stormwater plans, and acknowledging how multi-functional green infrastructure facilities can benefit the broader economic development strategies and capital improvement plans for our cities, we can provide long-term cost savings, while supporting resilience and enhancing the quality of life in our communities.


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