‘Sponge park’ to store rainwater

A “SPONGE park” to capture and store rainwater is being experimented in Pudong.

Grassed ditches, water-penetrating walking paths and wetlands will help to store rainwater at the 14,200-squaremeter renovated park in Lingang area along the East China Sea.

At the park’s public square, pavements have been replaced by bricks that allow water to penetrate at a faster rate and reduce water pooling on the roads even during heavy rain, the Shanghai Municipal Engineering Design Institute (Group) Co said yesterday.

The rainwater experiment is being trialed before the “sponge city” blueprint is implemented citywide. Neighborhoods, streets and greenery lands will be able to capture and store rainwater and ease the impact on the city during both rainy and arid seasons.

The “sponge park” experiment in Lingang involved a total investment of 8 million yuan (US$1.27 million). Rainwater is collected through pipelines and transferred to ponds and wetlands where it is purified with water plants.

The project will also curb pollution as rainwater is purified before being discharged into nearby rivers during heavy rain, said Lu Yongpeng, assistant director with the “sponge city” research center.

The water-penetrating bricks have also been installed at parking area. Each parking slot has a piece of grassland in the middle which can prevent water pooling. They will also be introduced citywide in new parking lots.

The city government is also turning a 79-square-kilometer region of the Lingang area into China’s largest “sponge city” pilot zone. The area near the Hangzhou Bay is reclaimed land from the sea. It has an artificial lake, the Dishui Lake, and its streets are designed like ripples from the lake.

On its completion next year, the region will be able to resist floods. The park alone can absorb a total of 158 cubic meters of rainwater and store another 190 cubic meters in the ponds and wetlands.

Nearly half of the projects in Lingang have been completed, Lu said. They will also cover neighborhoods, streets and public plazas as well as waterways.

Shanghai aims to create 200 square kilometers of sponge regions that can collect and process up to 70 percent of the rainwater by 2020.