The city HuaXin is located in the greater Shanghai area. Cities in this region are often referred to as the “Venice of the East” because the extremely densely populated estuary of the Yangtze River is traversed by many streams.
Having no adequate infrastructure for their disposal of waste (including wastewater), the arising sewage is often diverted and transported into the rivers. According to that, the waters are mostly polluted and contaminated.
The Department of the Environment of Shanghai invited us to submit a draft of a constructed wetland. As there was not very much space available in the populous city, we suggested one could build a sewage treatment plant in the channel where the sewage is drained off.
First of all, a preliminary draft was sketched. At a later date, the project was realised.
The constructed wetland is designed for 80,000 litres of wastewater per day. The sewage comes from a nearby indoor market and several apartment blocks.
Technical College, Zhoushan
On the island of Zhoushan, south-east of Shanghai, a vertical flow (VF) wetland was built in a short construction period. It purifies the wastewater from 1,200 students. On the basis of its process stability, it does pretty well regarding its performance not only on school days but also during the holidays, when it is ‘underloaded’.
Yangshan Deep Water Port
Despite limited floor area, a constructed wetland has already been proposed at the planning stage of the deep-water port in Shanghai in order to purify the wastewater from its offices.
The wastewater is cleaned by a vertical-flow soil filter and subsequently collected in a cistern. Aside from that, the purified water is exclusively reused for the toilet and the urinal flushing.