Karachi opens Pakistan's first sponge park to hold monsoon rain

A water-sensitive sponge park at Jamali Park in Karachi's Gulberg Town, built to hold monsoon rainwater back from the city's drains and reuse it, was inaugurated this week in a partnership between WWF-Pakistan, the Gulberg Town Municipal Corporation and a private partner.

Dawn reported that the park can hold up to 100,000 gallons of water during monsoon events. The Express Tribune reported that construction took six months and that the inauguration was held on Thursday.

The system collects rainwater and water from the ablution facilities of a nearby mosque. Both pass through filtration stages, after which the water is stored underground or in tanks and reused to irrigate the park's plants and trees.

Filters installed beneath the park's water channels were developed locally, according to The Express Tribune. They use layers of gravel, sand, silica, activated carbon, biochar and zeolite. Gravel and larger material remove soil and debris, sand and silica trap finer particles, activated carbon and biochar absorb chemical and organic pollutants, and zeolite reduces certain heavy metals before the water reaches storage.

Naim Ashraf Raja, director of biodiversity at the Ministry of Climate Change and Environmental Coordination, told The Express Tribune that underground freshwater reserves had been heavily extracted through boreholes and other methods, and that replenishing them through natural processes was necessary. He said such projects were needed so that future generations did not face worsening water shortages.

Gulberg Town Chairman Nusratullah called the inauguration a milestone, saying the effects of climate change were visible even in European countries and that urgent measures were needed to conserve water.

Sohail Ali Naqvi, director of WWF-Pakistan's Freshwater Programme, said the organisation revised its strategy about 15 years ago and began water projects with the private sector in Lahore in 2012. He said locally sourced materials, including soil and small stones, were used to make the filters in Karachi.

Dawn reported that WWF-Pakistan worked on the project with GSK, the pharmaceutical company. The Express Tribune described the third partner only as the private sector.

The park includes an area where residents can scan barcodes to obtain plants, among them tamarind, almond, peepal and gulmohar. Those who take a plant commit to caring for it and to staying in contact with the park administration so its growth can be monitored. Separate areas are set aside for biodiversity and for butterflies.

Karachi, a densely populated coastal city, faces intense rainfall, urban flooding and water shortages, and much of it is covered by concrete, tiled surfaces and paved roads that keep rainwater from soaking into the ground.

China launched a national sponge city programme in 2014, building water-absorbing parks, artificial reservoirs, wetlands, green roofs and permeable pavement in cities including Wuhan and Shanghai. Copenhagen adopted a cloudburst management plan after severe flooding in 2011, Rotterdam developed water squares, and Singapore turned concrete drains into natural waterways under a national programme.