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ENVIRONMENT Resource conservation
View of the wetland in Heituw Bay Image 10
(Voigt Ingenieure GmbH/BWA Beijing, photo: Kaden, 2007)
Image 11
Huangshuihe
watershed
A reservoir cascade to enrich the ground water Image 12
Photo: Dr Luo, DHI-WASY GmbH
and installed. The main principle of the
(quantitative) monitoring concept is that the
water level in each of the planned shafts is
continuously measured using SEBA ® dippers.
If the water levels between the last two
successive chambers (distributor shaft and
sink hole) are known, the throughflows between
these two chambers can be calculated
using a vortex valve from UFT; the seepage
rates can then be calculated on this basis as
well.
Regionalisation of the results for Beijing
only revealed a total infiltration potential of
around 63 million m 3 /a. Juxtaposed with
this is an estimated water demand of around
1,700 million m 3 /a. Enriching the groundwater
by means of rain water is therefore
only a limited solution to the water deficit
problem. Coupled with this is a series of
further objective and subjective problems
with regard to acceptance of this:
❙ the effects enriching the groundwater are
not visible
❙ due to the irregular distribution of precipitation
in Beijing, relevant enriching of
the groundwater can only be achieved
during the summer months
❙ enriching the groundwater with rain water
requires a wide range of decentralised,
and possibly expensive, technical solutions.
It is obvious that these supply problems can
only be mastered by means of a bundle of
measures, e.g. saving water, using grey water,
river bank filtration and re-using wastewater.
Appropriate tests were used in the
joint project. Holistic assessments of this are
documented in Kaden et. al. (2006) /5/, for
example.
Due to different mentalities and perspectives,
working with the Chinese project
partners was not always easy. Extended
training and project visits of Chinese employees
to the German project partners were
very productive.
There is no doubt that this project, under the
management of Prof. Geiger, University of
Essen, succeeded in developing an understanding
for, and an ability to use, a modern
rain water management system in the Chinese
partners. Appropriate methods are now
standard procedure for the Beijing Water
Authority.
During preparations for the 2008 Olympic
Games in Beijing, the Chinese government
planned on making wide-ranging improvements
to the environmental situation in the
region. A central role in this was played by
two large artificial lakes within the park
which were to be completely supplied with
wastewater which had been treated.
2008 Olympic Games project
Following the above-mentioned project, the
joint project “Sustainable water concept and
its use in the 2008 Olympic Games” was
44 INTERNATIONAL
2011