The Summary of the 4th Stage”The 2nd year of TRWKR”

1. Water Quality
 The water quality in the Horikawa river on the 4th stage wasimproved better than that on the 1st , 2nd and 3rd stage.
The water quality (impression and COD), transparency, bubbling, smell on the4th stage was improved better than 1st ,2nd and 3rd stage.

 It was understood that water quality is better from spring to earlysummer than from fall to early winter.
The result of the 1st and 3rd stage as compared with the 2nd and 4th stage, wecould understand that the water quality (impression and COD), transparency,
bubbling, smell in the Horikawa river were different for the seasons.
1The Summary of the 4th Stage”The 2nd year of TRWKR”

1. Water Quality
 It was improved better the 2nd year than the 1st year..
It was improved better 2nd year than 1st year, compare with the result of 1st yearand 2nd year as the same season. The 1st and 3rd stage are same season as fromspring to early summer, and the 2nd and 4th stage are same season as from fall toearly winter.

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The Summary of the 4th Stage”The 2nd year of TRWKR”

2. Water Color The water color and the water impression of the Horikawa River
was changing step by step.
The color we could look many times was “pale gray yellowish green”, “grayyellowish green”, ”gray green”.
When we look these “pale gray yellowish green”, “gray yellowish green”, ”graygreen”, we felt unpleasant or little unpleasant at rate from 50% to 70%.
When we look the “dirty gray”, we felt uncomfortable or little uncomfortable at
rate to 100%. At the same time there was sludge rising to the surface. This color
could be seen at the 3rd stage (the survey from spring to early summer), we could
not see on the 2nd and 4th stage (the survey from fall to early winter).
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The Summary of the 4th Stage”The 2nd year of TRWKR”

2. Water Color The water color and the water impression of the Horikawa River
was changing step by step.
It was not large different about the water color between with TRWKR andwithout TRWKR. We need more research and accumulate of the survey date
for getting the influence to the water color, because the water color isinfluenced from the sunshine and the depth of the river.

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The Summary of the 4th Stage”The 2nd year of TRWKR”

3. Garbage■ The garbage decreased in the river.
The garbage of the plastics, cans, bottles in the river decreased on this 4th stage
than 1st stage.
It is considerd that the movement of cleaning the Horikawa is spreading graduallyby the consensus that the citizens who would like to clean up there.

5The Summary of the 4th Stage”The 2nd year of TRWKR”

4. Living Things■ The striped mullet ran up the river.
Many mullet ran up in the case at the 1st year of the TRWKR.

■ The waterweeds are growing the spot in the river.
There are growing waterweeds under the Sujikai Bridge, where were nowaterweeds in the river last year.
There were many dragonflies, fish, birds, tortoises in the waterweeds.
The mode of life was produced by food chain.
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The Summary of the 4th Stage”The 2nd year of TRWKR”■ The water quality in the Horikawa river on the 4th stage wasimproved because clarification ability of the river recovered.
Two years have passed since the start of TRWKR.
The water quality (impression and COD), transparency, bubbling, smell on the4th stage was improved better than the 1st year. And many waterweeds weregrowing in the river, many striped mullets ran up to the river. It was found thatthe change of these activities and ecologies around these living things.
It is consider that the environment in the Horikawa River in these two years wasimproved directly because of the effect of TRWKR.
Not only the purification activity like a TRWKR, but also the recovery ofclarification ability and citizens’ awareness for clean-up the river improved thewater quality.
We hope that the water quality of Horikawa will be improved more.
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