Civic Sanskriti: Giving life back to Pune’s life-giving Mula-Mutha river
Once the heart of life and culture of Pune, the Mula-Mutha has now become a receptacle for solid waste, sewage, and encroachments. The life-supporting functions of the river are significantly reduced as it passes through Pune.
The intention of the river rejuvenation programme must be to improve the health of the river as a natural entity. A healthy riverine ecosystem requires that its natural processes, flow regimes, and biodiversity be retained.
CEE and the Ecological Society conducted a scientific study of the Mula-Mutha river to develop an approach for restoration of the river ecosystem. A summary of the key recommendations* are presented here.
Riparian zone restoration
The riparian zone, that is the banks and flood plains along the flowing body of water, is the most critical element for biodiversity. This zone is a refuge for fauna, and can improve water percolation and reduce soil erosion.
Multiple past studies indicate reduction in species and populations of vegetation along the Mula-Mutha.
The report recommends restoration addressing the segment-specific damage:
From Warje, where the Mutha enters Pune, till Mhatre bridge: Removal of debris, and careful plantations of native vegetation mimicking the better segments of the river upstream, are recommended to restore the riparian zone.
From Mhatre Bridge to the Sangam with the Mula: Channels constructed in the past have resulted in a severely-degraded ecosystem with low biodiversity. Removal of man-made hard channels and debris, and recreating the riverbank habitats are recommended.
From Sangam and Naik Beyt till Mundhwa: The river has relatively better water-flow and lesser built-up structures. This was the segment that Salim Ali had wanted to declare as a bird sanctuary. The recommended approach here is: no further disturbance, let the river heal itself.
Walls, sewage pipes and roads destroy natural habitats in the ecosystem. Physical features like potholes, sandy surfaces on the riverbed, boulder piles, are rich habitats for different types of flora and fauna. These must be restored or re-created using natural materials.
Water quality is one the most important factors in river restoration.
No untreated sewage should be discharged into the river. An adequate number of decentralised sewage treatment plants, rather than few large STPs, is a critical need.
Measures to prevent truck-loads of debris and solid waste dumps into the river are also crucial.
Household chemicals contribute to deterioration of the water quality. Natural alternatives to chemical domestic products such as soaps, shampoos, detergents must be promoted.
Aquifers and hydrology
A minimum (environmental) flow of water should be maintained throughout the year to sustain life in the riverine habitats.
Streams such as Ambil Odha and Nagzari, and natural springs that feed the river should be restored along with the main river body.
Increased concretisation of the cityscape has reduced the area of exposed soil, in turn reducing water percolation and ground water recharge. It is recommended to limit the impervious surfaces along the riverbanks and in areas of higher groundwater recharge.
Flood control and encroachments
Every year as flood intensity increases, the rejuvenation programme must recognise the regulatory functions of a healthy riverine ecosystem. No further construction should be permitted within the blue flood-lines. The banks must be conserved as riparian habitat. Constructions within the flood lines must be relocated and debris removed.
Facilities for citizens
Since historical times people have been using the river for their daily needs. Now, since the river needs rest for its restoration, the need is to re-integrate fragmented open spaces into a continuous riparian zone. Human activities may be judiciously managed in an eco-sensitive manner, instead of opening up a continuous public realm.
Zones for grazing may be demarcated and fishing regulated to prevent over-exploitation. Dhobi ghats, vehicle and animal washing activities may be given alternative locations.
Existing ghats, places of worship and heritage structures along the river may be repaired and cleaned up, keeping to the existing built-up space. Facilities such as gardens, riverside nature trails, properly-designed eateries may be planned at a few locations.
The limited construction this would entail should take care to preserve the natural topography of the riverbank. The use of natural materials like mud bricks, lime, timber is preferred over the use of concrete. Manual labour, where feasible, is preferred over use of machines. Examples of innovative access barriers of natural hedges, board walks and zones for human use are presented in the report.
The ecological approach to riverfront development of the Mula-Mutha river, proposed by these NGOs, suggests segment-specific conservation of natural elements including meanders, banks, wetlands, streams and springs. It balances between benign neglect, managed ecosystem restoration and human use.
With Dr Swati Gole and Dr Gurudas Nulkar, Ecological Society
*Full text and maps available at https://www.ecological-society.com/mula-mutha-riverfront
Sanskriti Menon is senior programme director, Centre for Environment Education. She writes on urban sustainability and participatory governance. Views are personal. She can be reached at firstname.lastname@example.org