Water Storage in Mumbai Starts With a Park Bench
Mumbai faces increasing strains on its water resources – monsoons bring torrential downpour and flooding for four months, and then for the remainder of the year water needs to be pumped from increasingly distant sources. Though securing water is difficult in conditions of shortage, disparities in water access are visibly evident in the parks of the city. Lush, verdant spaces in affluent areas contrast with arid, dusty lots in poorer neighborhoods.
The Water Bench was developed as one of several “microsolutions” to explore approaches to the issue of water supply and access along with other challenges to Mumbai’s fragmented urban landscape, often divided between the slums and formal areas of the city receiving top-down planning and infrastructure.
The bench is available in three models of 500, 1,000, and 1,800 Liters (132, 264, and 475.5 gallons) made from partially recycled polyethylene. It is designed like a Chesterfield sofa, and is currently being prototyped in several Mumbai parks.
Can a humble park bench begin to solve challenges of increasing public access, providing for privacy and reflection, and strengthen the urban fabric through distributed, home-grown solutions? I was able to ask Anitra Baliga and Neville Mars with MARS Architects a few questions about their design. Their responses are provided here, edited for length with emphasis added:
Q: How was the particular idea of the water bench inspired?
The issue of water proved particularly telling as our research revealed that it is ineffective to consider any aspect from sanitation to surface water pollution or safe drinking water independently. Water is the most obvious great connector. We found that even the increasingly large water infrastructure, pumping in from reservoirs ever further removed from the city, is not able to keep up with demand. The conclusion was simple. We need to consider more local solutions. Rainwater harvesting was a particularly obvious choice as the regulations are already in place and the monsoons in Mumbai, at least in theory, are a sufficient annual source. The challenge is how to store water.
Q: Why was this particular design aesthetic chosen?
The Water Bench funnels water to the buttons which act as water inlets. This offers a comfortable slightly bouncy seating area with the added benefit that the surface is dry almost immediately after each rainfall. The size of the bench is intentionally awkward, encouraging up to three people on either side to interact and converse. A full Bench contains an above and an underground tank. Together the storage capacity of up to 1000 liters is well suited for Mumbai’s precipitation.
Q: How are public parks in Mumbai currently irrigated?
The Water Bench is an ideal standalone installation for small plots and private gardens. At the scale of the city, however, we have always considered the Water Bench as part of a larger group of water conservation solutions. To build an integrated water supply system we envision central and decentralized parts to work together at the neighborhood scale. Combined with water run-off and smart wells they can make parks and public spaces independent from district water supplies. These solutions work to lower demand, increase supply and create buffers to minimize the impact of floods and droughts. Together they complete the traditional infrastructure and make for a much more resilient and flexible water management system.
Q: What has been the initial reaction by local residents and officials?
The response has been rather positive. The benches are attracting locals across all age groups and urging park goers to engage in conversations. DNA newspaper in Mumbai interviewed 43 year old Vishal Joshi who was at the Horniman Circle Garden with his wife and kids: “I decided to take my family to the garden instead of a crowded mall after hearing about the Water Benches. I have specially travelled the distance to teach my children the importance of saving water”. Officials and park authorities have also expressed keen interest to install more benches across the city.
Q: What are the maintenance needs of the system?
The benches have been designed to comply with standards for water harvesting and storage, especially in the Asia Pacific region. The portable pump that comes with each bench can operate for 3 hours and is rechargeable and can be used to empty the bench if required. Since the benches are made of high density PE and anchored to the ground, they should be able to withstand Mumbai’s harsh conditions.
Q: How much will be the estimated cost?
A full bench, which includes a below ground unit is currently priced at $1000. The Water Bench is priced to compete with standard park furniture or water storage systems, and combining these two functions is already great value for your money.
Q: How does this support and mesh with other water system strategies that you have been developing?
Mumbai has taught us some urgent lessons. Projects at both ends of the scale, either city-wide or community level, are crucial, but these would be much more effective if their efforts would be aligned to each other. The water harvesting installations we’ve proposed could be integral parts of existing structures, such as skywalks and stations, while storage solutions are integrated within the walls of homes. Steadily, we hope, the traditional silos between engineering, architecture, planning and product design will be replaced by more cross-disciplinary and holistic methodologies.
Pursuit of Integrated Solutions
In its prototyping phase, the Water Bench will need to prove itself in a rugged urban environment. Will the costs and maintenance of batteries prove to be prohibitive? Will rainwater in the benches retain some purity under public uses of the benches? One of the intangible but essential values of something like a park bench was explored through hand-drawn visual responses in a participatory research project asking how Mumbaikars find personal escape in public spaces. Their key findings were:
- Most participants often found privacy in public spaces containing an architectural element such as street furniture or playground equipment.
- Participants attained privacy in large open spaces such as seafront promenades and maidans (open spaces often used for sport or large gatherings).
- A sense of belongingness, security, ownership, seclusion, personalization of the space, accessibility, and freedom of expression were essential to fostering a sense of privacy in public space.
The Water Bench is only one of the ideas developed in this collaboration with the BMW Guggenheim Lab, a mobile urban think tank and community center that touched down in Mumbai for 6 weeks to offer programs, interactive and hands-on events, and discussions for the general public of all ages. Designers, policy makers, implementers, and city dwellers participated on projects including re-envisioning a junction that has one of the highest traffic volumes in Mumbai, with about 60,000 drivers and cyclists passing through per hour.
Here are some additional solutions designed by the team to further integrate and supplement the water system:
- Water Wall – Since water storage is critical for rainwater harvesting purposes, this solution would store cleaning and potable water separately in modular wall cells that are connected to roof, can be removed, and serve as clear walls to allow daylight penetration (along with UV disinfection). Transforming slum walls into new water walls is certainly an aesthetically tantalizing prospect.
- Groove – To solve multiple issues of comfort and land shortage, urban farming trays could be placed above roofs to serve as urban gardens, thereby reducing the monsoon’s loud drone on corrugated roofs and serve to shade and cool dwellings from relentless summer heat.
- Weather Tap – This solution offers a combined rainwater catchment and solar desalination structure that can contribute to distributed water storage and supply.
As a park seat, the Water Bench may not be a high tech marvel but it is a compelling design experiment that will hopefully spur discussion on how public spaces can perform multiple functions in solving both practical and social urban challenges.