Project Overview:Jiatianxia community is located in the west of Huairou old city, north to fule street, West to Qingchun Road, South and east to current buildings. The building density of the project area is 30%, and there are 10 buildings in the community, without underground facilities; there is a landscape water system and two underground water pools in the center of the community, with the volume of 640 m3 and 40 m3 respectively.

Overall objective:With the construction concept of sponge city as the core, measures such as infiltration, stagnation, storage, purification, use and drainage are adopted to build a rainwater and flood management system integrating water collection, storage and use.

Design strategy:
•Keep the current situation of better ground pavement and greening, and reduce the changed area;
•Make full use of the existing rainwater pipeline and rainwater storage tank, and rebuild the reuse system;
• functional restoration of landscape water system;
• installation of typical lid facilities (rainwater tank, grass planting ditch, rainwater garden, sunken green space, step greening);
•Set up sponge billboards and facilities display windows;

When the sponge facilities of the project are arranged, the existing rainwater system shall be fully utilized to rearrange the water flow organization in the community:

•Adjust the surface runoff organization to increase the source control and purification capacity;
•Increase overflow outlet, transform diversion well and increase rainwater storage capacity;
• rebuild the rainwater recycling system to increase the rainwater recycling capacity.