Thank you to Professor Husain Chang in the landscape architecture department for inviting me to give a web-based lecture to her Contemporary Eco-City class. This talk covered stormwater planning, analysis, and design to support China’s Sponge City program. Massive green stormwater projects are happening at a breakneck speed and using the right analysis and design tools are essential to meet to goals of this program. GEO is one of the few foreign firms at the forefront of this program with active construction projects in Zhenjiang, Ningbo, and Wuhan.
GEO’s engineer, Yi Yang and John Lenth, Herrera Environmental Consultants coordinated a tour of Sponge City stormwater facilities in Zhenjiang, China. We were honored to have Zhang Linwei from the central government Ministry of Housing and Urban-Rural Development attend. Mr. Zhang is one of the chief architects of China’s Sponge City program, a multi-billion dollar stormwater retrofit program in select Chinese cities. The tour was followed up by a stormwater monitoring presentation and discussion lead by both GEO and Herrera.
Construction of all 23 Gravity Swales™ is almost complete. These stormwater treatment facilities capture and treat all the campus’s stormwater pipe discharge entering the Yudai River. They are designed to filter small rain events and safely overflow larger storms. The swales will soon be vegetated with emergent wetland plant species and fully integrated into the landscape plan.
GEO recently attended a project team get together at Russell Investment’s Sky Garden hosted by the project developer, Pine Street Group. GEO is working with MKA in providing stormwater design and analysis and leading the Salmon Safe Certification process for this $1.6 Billion project.
We are providing a comprehensive stormwater quality solution for all stormwater runoff generated within the university campus and entering the Yudai River which borders the campus. The goal of this project is to meet to meet Class IV water standards in the Yudai River. The design team developed treatment facility sizing tools to design 23 Gravity Swales™ at each stormwater outfall. The Gravity Swales™ is a gravity fed bio-retention technology using high performance media in combination of TSS removal technology. A total treatment area of 11,606 m2 is being provided.
Regional stormwater treatment facilities are an alternative solution to parcel based low impact development (LID) when trying to meet water quality treatment goals in urban settings. Urban retrofit projects are challenging due to many site constraints (i.e. narrow median strips, lack of green or open spaces, and areas built on structure) . Our design team needed to look beyond parcel scale approaches and identified larger sites to provide regional treatment. In ZhenJiang, China, we designed a system called the Waterfall Treatment System (WTS) that is only 2000m2 but capable of treating runoff from a surrounding 120 ha area. This high-performance system contains a gravity pre-filter bay, followed by dispersion weirs and four engineered media filter beds. Under drains collect the filtered water at an infiltration rate of 100 cm/hr. Currently under construction, the system is designed to removal 80% total suspended solids, 50% total phosphorus, 60% dissolved zinc, and 30% dissolved copper. This type of system should be added to your suite of tools when addressing stormwater water quality improvements in urban settings.
Location: Washington State University ,Puyallup Campus
GEO worked with SWA Group (the landscape architect) in designing a 4km waterway that will connect an existing and future lake. This waterway ranges from 30 to 50 meters in width weaving its way through planned residential and retail neighborhoods. We built a Civil 3D surface to determine the optimal waterway alignment and calculated cut and fill volumes. A total of 2,300,000 cubic meters of material will eventually be excavated and used to support adjacent development projects. We will keep you posted on progress!
Xing Yuan New Town Waterway Planning and Design, Hanzhong, China
My daughter wonders what we do with water at GEO. Well, here is one example (click below).
HOW TO DESIGN A LAKE SYSTEM (PDF)
GEO wishing the best to friends and family in this New Year!