Last updated: June 2024
The Neela Hauz lake, part of the Neela Hauz biodiversity park, is a natural depression that was once a major source of drinking water for south Delhi, India (Ref 1). Due to nearby road construction and neglect, the lake was filled with solid waste and construction debris for many years. In 2015, based on the request of neighbourhood colonies, the Delhi High Court ordered the restoration of the lake. The Delhi Development Authority (DDA), in collaboration with the Centre for Environmental Management of Degraded Ecosystem (CEMDE) of the University of Delhi, carried out the restoration and revival of the lake using a Constructed Wetland System (CWS). Using the help of natural landscaping composed of oxidation ponds, pebble beds, and furrows having aquatic plants, now the sewage from nearby residential colonies is treated before passing it to the lake (Ref 2). The wetland now converts approximately 1 million litres of sewage per day which has resulted in satisfactory water quality levels (Ref 1). The lake, along with the surrounding biodiversity park, attracts many migratory birds and is also a tourist attraction point in the city. The success story of the lake now has become a model case for the revival of other lakes in the city (Ref 1).
Neela Hauz: A dumping ground transformed into scenic landscape
Ref. 4.
Overview
Nature-based solution
- Blue infrastructure
- Lakes/ponds
- In-land wetlands, peatlands, swamps, and moors
- Parks and urban forests
- Large urban parks or forests
Key challenges
- Green space, habitats and biodiversity (SDG 15)
- Habitat and biodiversity restoration
- Habitat and biodiversity conservation
- Green space creation and/or management
- Regeneration, land-use and urban development
- Promote natural styles of landscape design for urban development
- Water management (SDG 6)
- Stormwater and rainfall management and storage
- Improvements to water quality
- Health and well-being (SDG 3)
- Creation of opportunities for recreation
- Inclusive and effective governance (SDG 16)
- Inclusive governance
- Effective management
- Social justice, cohesion and equity (SDG 10)
- Environmental education
- Economic development and employment (SDG 8)
- Tourism support
Focus
Management and improved protection of rivers and other blue areas, Ecological restoration of ecosystems, Protection of natural ecosystems
Project objectives
The overall goal of the project was to restore the Neela Hauz lake, part of the Neela Hauz biodiversity park, to its original state (Ref 1, 2).
Specific goals of the intervention include:
1. Development of a Constructed Wetland System (CWS) to treat sewage water through bioremediation. (Ref 1, 2, 3)
2. Desilting of the lake bed to enhance the storage capacity of the lake. (Ref 1)
3. To support a variety of aquatic birds and contribute to the ecological health of the biodiversity park.
4. To maintain the ecological balance in the biodiversity park by planting native tree species.
5. To improve the aesthetics by "landscaping the area and creation of mounts that offer a picturesque view of the area" (Ref 3);
Implementation activities
The lake was critical to maintain water levels in south Delhi, especially the Mehrauli block, where the water table
had fallen drastically. It was decided to use raw sewage mixed with STP-treated water to maintain water levels in the lake since it is otherwise dependent solely on rainwater. Desiltation of the lake had increased the lake's depth and ability to store water. The silted materials were used for the landscaping in the area and for creating mounts to allow recreation and tourism (Ref 1, 3). A system of constructed wetlands was developed comprised of two open oxidation ponds and three physical treatment plants with different gradient channels and a mix of pebbles, gravels, and furrows with aquatic plants (Ref 1). The raw sewage and STP-treated water (designated as wastewater) passed through a constructed wetland system before it enters the lake. (Ref 2). More than 10,000 native species were planted by 4000 students and locals (Ref 2). This process uses zero energy natural process to clean sewage water and utilize this as the main source of the lake's input. The water is purified by storing raw sewage in vacant land for oxidation and aerobic digestion and storing sewage water in ponds with a variety of aquatic plants capable of removing toxic chemicals (Ref 1, 2, 3). The implementation activities also include developing walking trails around the lake with proper sitting areas for recreation (Ref 3). After the revival of the wetland, the site is now used as an example of ecological restoration for educational purposes (Ref 3).
Biodiversity conservation or restoration-focused activities
Biodiversity conservation:
- Protect and enhance urban habitats
- Promote environmentally-sound development in and around protected areas
- Protect species
- Undertake specific measures to protect species
- Undertake specific measures to protect native species
- Means for conservation governance
- Create and use scientific knowledge for conservation
Biodiversity restoration:
- Rehabilitate and restore damaged or destroyed ecosystems
- Restore species (native, endangered, or unspecified)
- Restore native species
Main beneficiaries
- Local government/Municipality
- Researchers/University
- Citizens or community groups
Governance
Management set-up
- Co-governance with government and non-government actors
Type of initiating organisation
- Local government/municipality
- Researchers/university
Participatory approaches/ community involvement
- Joint implementation (e.g. tree planting)
Details on the roles of the organisations involved in the project
The Centre for Environmental Management of Degraded Ecosystem (CEMDE), Department of Environmental Studies, University of Delhi provided the technical inputs and carried out the implementation, while Delhi Development Authority (DDA) provided the funding for implementation (Ref 1, 3).
Project implemented in response to ...
... an EU policy or strategy?
No
... a national policy or strategy?
No
... a local policy or strategy?
No
Financing
Total cost
Unknown
Source(s) of funding
- Public local authority budget
Type of funding
- Earmarked public budget
Non-financial contribution
Unknown
Impacts and Monitoring
Environmental impacts
- Environmental quality
- Improved waste management
- Water management and blue areas
- Improved water quality
- Improved stormwater management
- Enhanced protection and restoration of freshwater ecosystems
- Green space and habitat
- Increased conservation or restoration of ecosystems
- Reduced biodiversity loss
- Increased number of species present
- Restoration of derelict areas
Economic impacts
- Unknown
Socio-cultural impacts
- Health and wellbeing
- Gain in activities for recreation and exercise
- Cultural heritage and sense of place
- Increased appreciation for natural spaces
- Education
- Increased support for education and scientific research
Type of reported impacts
Achieved impacts
Presence of formal monitoring system
Yes
Presence of indicators used in reporting
Yes
Presence of monitoring/ evaluation reports
No evidence in public records
Availability of a web-based monitoring tool
No evidence in public records
References
1. Jaggi, M. (2017), Neela Hauz Biodiversity Park - From Barren to Beautiful. 54(06). Science Reporter, available at - Source link (accessed 23-01-2023)
2. Delhi Biodiversity Foundation (no date), available at Source link (accessed 23-01-2023)
3. Singh P 2019, Once a dumping ground, Neela Hauz now a soothing site. Business Standard, 17 May, Source link (accessed 23-01-2023)
4. Onmanorama news: Neela Hauz: A dumping ground transformed into scenic landscape, 17 May 2019, viewed on 15 February 2023, Source link (accessed 23-01-2023)
2. Delhi Biodiversity Foundation (no date), available at Source link (accessed 23-01-2023)
3. Singh P 2019, Once a dumping ground, Neela Hauz now a soothing site. Business Standard, 17 May, Source link (accessed 23-01-2023)
4. Onmanorama news: Neela Hauz: A dumping ground transformed into scenic landscape, 17 May 2019, viewed on 15 February 2023, Source link (accessed 23-01-2023)
Neela Hauz Biodiversity Park
Ref. 2.
Before and after restoration
Source: https://www.delhibiodiversityparks.org/neela-hauz.html
Information about this nature-based solution was collected as part of the "NBS 2022" UNA Asian extension project funded by the Asia-Europe Foundation.