Rivers are considered lifelines yet garbage piles, people encroach and untreated sewage pours, unabatedly. Rivers flowing through urban India, except for the Sabarmati in Ahmedabad maybe, speaks of our collective apathy and insatiable greed.
In urbanized areas small, headwater streams are often buried and forgotten. As cities develop with roadways, parking lots, and buildings; waterways are sometimes redirected into a drainage system to create more buildable plots or for preventing floods. Chennai airport extends over the Adyar river, affecting its long-term safety and stability. The runways of the Mumbai airport have been built over the Mithi river, and the airport is located on a reclaimed pond. Unfortunately, covering, burying or encroaching water bodies and streams increases nutrient pollution, and causes biodiversity and habitat losses through unpredictable inundation with enormous socioeconomic consequences.
Around the world is a recent phenomenon in river restoration called “daylighting.” It involves removing obstructions to free flow, resettling squatters with dignity, dismantling pavement covers and nurturing waterways to their pristine condition. The river or stream gets a new lease of life resulting in numerous aesthetic, economic, and environmental solutions even while reclaiming its evolutionary role as a flood water carrier.
As daylighting re-discovers buried and narrowed waterways, polluted runoffs decline and livability of the adjoining built environment improves. Water treatment costs are lowered because stormwaters do not enter sewer systems. Revitalising streams helps Municipalities gain ecological and water quality benefits, such as improved habitats and balanced nutrient retention. Daylighting restores floodplains, increases hydraulic storage, reduces channelisation, slows down the water and removes choke points such as culverts where water backs up submerging habitats. It could be a cost effective and sustainable alternative for flood control and embankment maintenance.
Recommendations for enhancing the use of stream daylighting as a tool to vitalise water resources requires government intervention with new laws supported by scientific research and monitoring mechanisms for comprehensive guidance.
Adoption of a daylighting database with standard parameters will enable third parties to grade and certify project implementation measures. Realisation by businesses that daylighting of rivers is an environmental protection activity deserving CSR funds will catalyse river restoration. Such fundamental changes will galvanise urban communities, create interest in clean water, community health, and flood mitigation.
Currently, there are a suite of practices used to control stormwater runoffs including bio-retention, rain gardens, and green roofs. However, daylighting could add to this repertoire.
But all this is possible only with dismantling of governmental policy barriers, speedy judicial redressals, comprehensive scientific data collection and espousal of river restoration by thought leaders to drive urban renewal. Communities must find inspirations to improve their environment. Daylighting projects in both Kalamazoo, Michigan and Yonkers, New York illustrate the benefits to flood mitigation and community revitalization, respectively.
Daylighting of Indian rivers will also require a groundswell in awareness, concerted public action, corporate involvement and non partisan politics to succeed. It cannot be a one time event but a long drawn perseverance. Thanks to Reciprocity Foundation, September 30, the International Rivers Day will mark the beginning of a 6-month campaign to “Save the Adyar River Today.” You could engage with them to include Daylighting among the suite of techniques to improve urban environments. It may seem difficult to start, too monumental, but let’s begin! Let’s Daylight to Delight our Future!
Twitter: Pavitra Sriprakash @pavisriprakash
The writer is an architect, urban designer, dancer and chief designer at Shilpa Architects