Local government/municipality

The ‘City of 1,000 Tanks’ project offers a holistic solution to the problems of floods, water scarcity and pollution in Chennai (Ref. 1). The project's primary objective is to develop a "Water Balance Model" for the city, which involves collecting rainwater, treating wastewater and runoff pollution with decentralized nature-based solutions, as well as prevent climate-change-induced droughts and saline intrusion due to sea-level rise (Ref. 1, 2). This is achieved through developing various nature-based water management solutions and improving the recharge capacity of traditional temple tanks (Ref 1).
The project began in 2018, following the call for action event of the "Water as Leverage for Resilient Cities Asia" (a bilateral program spanning several Asian countries). The Water Balance Model is developed as a strategy with an incremental implementation process (Ref 1, 2). The project started with pilot projects and then progressed to flagship projects before full city-wide implementation (Ref. 3).

In 2021, the local municipal government of Navi Mumbai City and a local NGO converted a neglected urban space used as a dump yard in Nisarg Udyan into a healthy and dense forest (Ref 1,2). The aim of the project was to improve biodiversity and complement the local ecosystem, choosing specifically native species from the local area for plantation (Ref 3). By applying the Miyawaki forest technique, the project was able to transform the wasteland into a 3-acre mini-forest quickly. A civic officer on behalf of the Navi Mumbai Municipal Corporation (NMMC) drove the re-forestation project jointly with the support of Green Yatra, a local NGO, and corporate social responsibility (CSR) funding support from Sony Music Entertainment (Ref. 1, 3).

A 7-hectare pilot public project, the Tebet Eco park is located in South Jakarta in a neighbourhood that is densely populated. Previous to the intervention the park was in an acute state of deterioration and prone to floods as well as ecological degradation, as the park is streamed by a river which made it only more susceptible to heavy rains. As such, the municipal authorities of Jakarta planned to revitalize the area by " increasing the hydraulic capacity of existing canal, improving site-wide pedestrian connectivity, and adding new recreation program". This meant that the park was transformed by planting and conserving new and older trees, as well as using vegetation and natural embankments. Furthermore, the implementer planted riparian vegetation to improve water quality by filtering and cleansing surrounding runoff, which also enhanced the site's biodiversity. Besides these elements, a thematic garden, a forest buffer, and a community garden were implemented complementing the entire eco-design that the park aimed for. The park's rehabilitation focused greatly on the human element as it was paramount to provide maximum benefits for park users, the surrounding natural habitats and species, as well as increasing the land value of the area. (2,3,7)

In 2018, the Bulat Utemuratov’s Foundation began reconstruction works at the main Botanical Garden in Almaty at the request of the Institute of Botany and Phytointroduction and with the support of the governor of Almaty city [1, 5, 6]. The goal of the project was the restoration of the botanic garden with preservation of its original green character and the modernization of its infrastructure [2, 5]. Taking into account the special status of the Botanical Garden and the high public interest in the reconstruction project, the Foundation ensured full transparency to the public. Taking public recommendations into considerations, the schematic design of the reconstruction was approved in the autumn of 2018 [6]. The project also aimed to do no harm to the existing flora and fauna of botanical gardens, and apply new technology to provide long service life to the garden [1, 4].

To achieve the project's goals, the water supply system was restored, drip and auto irrigation systems were created. Around 174.3 thousand plants were planted, including more than 1300 trees. Additionally, 50 thousand sq.m of roads and paths were repaired, lighting systems and video surveillance systems were installed, and the garden furniture was renovated [1]. The project also resulted in the development of three new entrance pavilions with an electronic ticketing system. A mobile application with a garden map and a description of the green areas has been developed [5]. Special attention was paid to the accessibility of all zones of the Botanical Garden for low-mobility groups. [1, 4, 5, 6].

Confirming the success of the project, within three months after the reconstruction was completed, over 210 thousand persons visited the Almaty Botanic Garden [6].

Kempegowda International Airport Bengaluru (KIAB)'s new terminal 2 is an environmentally friendly initiative that uses innovative methods to maintain ecological sustainability using native plants (Ref 1, 2). The terminal was built on four guiding principles: technology leadership, being a terminal within a garden, environmental and ecological stewardship, and a celebration of Karnataka’s rich heritage and culture. Through the "terminal within a garden" project, the aim was to create a calming and relaxing space for passengers using greenery for visual appeal as people pass through the airport (Ref 1). Hanging gardens, trees, and green walls are the primary nature-related features included in the terminal and an outdoor greenbelt around the terminal. The airport uses native plant species, including trees, flowering plants, and shrubs (Ref. 2).
The terminal area also includes water bodies, cascades, and miniature waterfalls to maintain the natural atmosphere. The terminal also has extensive rainwater harvesting and groundwater recharge facilities (Ref 1). Other sustainable goals in the terminal area include energy saving, water conservation, waste management, and pollution control measures (Ref 2).

The Rajakori lake rejuvenation project aimed at reviving an existing lake using a natural and sustainable treatment system, the "Scientific Wetland with Active Biodigester (SWAB)". SWAB technology uses a two-step process involving (i) a sedimentation tank equipped with a biodigester and (ii) a constructed wetland system. The untreated sewage waste is passed through this two-step process that uses microbes and plants to reduce pollutant levels. The project also involved redeveloping the public space around the lake for community use (Ref 1,2). Before 2017, the lake was overfilled with sewage and waste from nearby neighbourhoods due to a lack of proper sewage management. Initiated by the Delhi Government, the project aimed at using low-cost natural methods rather than conventional techniques involving concretized bases and chemicals to treat water (Ref 1, 4). Due to its success and cost-effectiveness, this project now serves as an excellent example for other projects within Delhi (Ref 5).

In 2008, Mahidol University in Thailand announced its revised five-year Green Campus master plan titled 'A Promised Place to Live and Learn with Nature' for its main Salaya Campus. The scheme aimed to promote a green conscience and lifestyle for its students and faculty through sustainable campus developments that consider social and environmental aspects. The university's objectives were to achieve energy conservation, environmental sustainability, and social cohesion and well-being. The main features of the master plan included the creation and maintenance of green open spaces covering at least 70% of the campus premises, optimization of land use, transformation of infrastructure to encourage cycling, creation of outdoor learning, recreational and research areas, and enhancement of local biodiversity. The master plan also covered guidelines and targets for energy consumption, waste, and water management in the campus buildings. The Siri Ruckhachati Nature Park, the university's arboretum, was also redesigned with green and blue areas playing a role in flood management. Following the 'Green Campus' master plan, Mahidol University developed its existing mission further and became an 'Eco University' in 2012 and a 'Sustainable University' in 2021. These two missions focus primarily on reducing energy consumption and waste management.
(Ref.1,2,3,12)

Balili River, situated in the province of Benguet, is among the many urban rivers in the Philippines that suffer from severe pollution due to various human activities. Indiscriminate dumping of waste in almost all of its 23 tributaries is a significant contributor to the pollution. Despite this, the river remains a critical source of irrigation for farmers in La Trinidad who primarily grow strawberry and salad crops in the valley. However, the use of contaminated water from the river poses a direct threat to the food safety of consumers of these crops. Moreover, during the summer, the black water of the Balili River is a constant eyesore in the community. To address these environmental concerns, a pilot study was conducted aimed at exploring treatment options for the polluted water in Balili River. The study focused on assessing the use of local plants to restore biodiversity, conserve wildlife habitats, and test the phytoremediation potential of local macrophytes. The pilot area was established within the Organic Farm of Benguet State University near the main stream of the Balili river. The study set up two types of constructed wetlands (CW), a surface flow CW for floating plants and a horizontal subsurface flow CW for emergent plants. The results of the pilot study suggest that constructed wetlands could be an effective solution for cleaning up the Balili River. The implementation of constructed wetlands in Balili River can not only improve the water quality but also benefit the local community and ecosystem. [1,2]

Vinh is the biggest city in north-central Vietnam and is the hub for economic and cultural development in the region. As of 2018, the city has a population of approx. 500,000 inhabitants and is located on the Ca River delta, 160 miles (260 km) south of Hanoi. Flooding and poor environmental sanitation are major impediments to the development of Vinh City. The drainage system of the city is comprised of four catchment basins connected to Rao Dung, Ke Gai, Vinh and Lam Rivers. Among the four, the Vinh River is flowing through the central wards and communes of Vinh City and is one that becomes sensitive to severe flooding events frequently (2,3).
Recently (in 2021), with support from the World Bank, the government initiated a program, the Vinh City Priority Infrastructure and Urban Resilience Development Project (VPIUR), which is expected to bring a new look to the river, reduce the risk of flooding in urban areas and strengthen urban management capacity to adapt to climate change. This project has several sub components and one of them is a river rehabilitation and upgrade under the form of riverbank green, sanitation, and flood risk management (1, 3).
The implementation includes a comprehensive set of structural and non-structural interventions, including flood control systems and nature-based solutions, wastewater collection and treatment infrastructure, and key transport links. The project aims to transform it into green public spaces which are to be constructed under the project. The project also aims to invest in developing green public spaces along the Vinh riverbank and a new regulation lake. (3)

In 2005, a constructed wetland was established in Barangay Villareal, Bayawan City in order to improve a peri-urban settlement and promote domestic wastewater treatment with reed beds. The wetland covers an area of 2680 square metres and comprises two reed beds, with the first bed utilizing perforated pipes beneath a sand and gravel substrate for vertical flow filtering, and the second bed utilizing horizontal flow for biological filtering. The roots of the Phragmites karka reeds, which are used in the system, act as a natural filter, removing microorganisms and pollutants. The treated effluent is reused for various purposes, such as watering plants, firefighting, and irrigating ornamental plants and agricultural crops. The overarching objective of the initiative is to safeguard coastal waters from pollution caused by domestic wastewater and enhance residents' quality of life by providing safe sanitation and wastewater treatment facilities. Furthermore, the initiative seeks to showcase the effectiveness of constructed wetlands, encourage the use of locally available reeds for wastewater treatment, and conserve water and nutrients by reusing treated wastewater. [1,2].