Water Environment Soundness Index (MIZU-SHIRUBE in Japanese)Let’s go to a river together !

Water Environment Division,Environment Management Bureau, Ministry of the Environment,-0Water Environment
Soundness Index (2009)Water Environment Soundness Index (MIZU-SHIRUBE in Japanese) – The nickname, MIZU-SHIRUBE,
comes from a word for road sign, MICHI-SHIRUBE, and means a sign giving information or instructions toriver users.

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Contents・・・・・・・・・・・・・・・・・・・・・・

3(1) What are the characteristics of rivers? ・・・・・・・・・・・・・・・・・・・

3(2) How to investigate a river environment ・・・・・・・・・・・・・・・・・・

3(3) Five indices ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

6- Natural state ・・・・・・・・・・・・・・・・・・・・・・・・・・・・

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1. How to study a river environment- Rich in plants and animals ・・・・・・・・・・・・・・・・・・・・・・ 10- Water clarity ・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 17- Pleasant waterfront environment ・・・・・・・・・・・・・・・・・・・・ 20- Regional water culture ・・・・・・・・・・・・・・・・・・・・・・・・ 25
2. Let’s go to a nearby river to investigate

・・・・・・・・・・・・・・・・・・・31(1) Before starting an investigation ・・・・・・・・・・・・・・・・・・・・・・ 31(2) Let’s make a preliminary inspection ・・・・・・・・・・・・・・・・・・・・ 32(3) What tools are needed?

・・・・・・・・・・・・・・・・・・・・・・・・ 33(4) Let’s go to the field ・・・・・・・・・・・・・・・・・・・・・・・・・・・ 34- Observation notes ・・・・・・・・・・・・・・・・・・・・・・・・・・ 35- Table of observation notes ・・・・・・・・・・・・・・・・・・・・・・・ 37
3. Dos and Don’ts in a river ・・・・・・・・・・・・・・・・・・・・・・・・・・・ 39

Vocabulary ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

40<For instructors>(1) Investigation period (2) Investigation site (3) Preliminary survey (4) Implementation of aninvestigation (5) Precautions for safety (6) How to use the investigation (results)-2-

1. How to study the river environment(1) What are the characteristics of rivers?
 Rivers vary in size from large to small: large rivers that we need to cross by boat and small
streams that run near our homes.
River conditions vary from place to place from a river in a mountain to a river in a town.
 There are living things such as fish, crabs, insects, and aquatic plants in rivers.
Grasses and trees grow at the edge of the river and birds living there too.
 Rivers have long been used for various purposes, such as fishery, agriculture, and drinking water.
In addition, it is an important place for local festivals and traditions, for example the floating
lantern ceremony.
 Each river has a different characteristic according to flowing water, scenery, living things andrelationships with our lives.
What are the characteristics of rivers near you?

(2) How to investigate a river environment
 Five indices are used to investigate the whole picture of a river environment, including the riverwater, the living things, the scenery, and its use in our daily lives.
 Each index has three to five items (called separate indicators) used to investigate the rivercondition.
Evaluate each separate indicator on a scale of 3 to 1 by observing the river conditions.
If possible, write the reasons why you chose your ranking.
 You can start with any indicator that seems appropriate.

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1. Natural stateThis represents how much nature is preserved in the water environment.
 Quantity of water

There is an abundant flow of water even on days without rain.

 Condition of riverbank

The river consists of natural soil, sand, or rock and is not covered
with concrete.

 Can fish go upstream?

Are there any obstacles in the river? Are there fish ladders?

2. Rich in plants and animals
This represents the variety and quantity of plants and animals in the water environment.
 Plants on the side of the river

Plants are growing on the sides of the river.

 Birds and bird habitats

There are birds and bird habitats on the sides of the river.

 Fish and fish habitats

There are fish and fish habitats in and along the river.

 Living things in the riverbed

Brown color algae are on the stones in the riverbed. Insects can befound.

3. Water clarity
This represents how clean and clear the water is.
 Transparency

The transparency is measured to investigate how clear the water is.

 Smell of the water

The water’s smell is checked to identify whether dirty water isflowing into the river.

 COD (Chemical oxygen demand)

The COD is measured to investigate how clean the water is in an
optional investigation.

4. Pleasant waterfront environment
This is investigated by the human senses: How beautiful and pleasant is the water
environment?
 Scenery (feel)Is the river scenery pleasant?

 Trash (visual)

Visual state of the river and riverside: trash, etc.

 Touching the water (touch)

The feeling on your hands and feet when you touch thewater or go into the river.

 Smell along the riverside (smell) Characteristics and intensity of the smell along the edge of the river.
 Sound along the river (audial)

Characteristics and intensity of the sound along the edge of the river.

5. Regional water culture
This represents the relationship between the water environment and the people.
 History and culture

Historical and cultural stories related to the river.

 Accessibility to the riverside

Is the edge of the river accessible?

 Daily use

Is it used for walking or sports activities on a daily basis?

 Industrial activities

Is it used for fishery or drinking water?

 Environmental activities

Is it used for environmental education or clean up activities by thelocal community?

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1. Natural state
Investigate how much nature is preserved in the river.
The following are three separate indicators to investigate the river condition.
-Is there an abundant flow of water?

-Does the riverbank look natural?

-Can fish go upstream?

Choose the appropriate answer for each question on a scale of 3 to 1 according to the river condition.
Write the reasons for your choice. The details on how to choose the scale are explained in the followingpages.
Scale
Question321-

Is there an abundantflow of water?

Abundant flow

Some flow

No flow-

Does the riverbank
look natural?

NaturalRestored, but
looks natural

Restored withmuch concrete

Can fish go upstream?

Yes.
Fish can go
upstream.

Yes, by using
devices such asa fish ladder

No.
Fish cannot go
upstream dueto obstacles.

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Reasons for yourchoice1. Natural stateQuantity of water
Is there an abundant flow of water?

Referring to the following pictures, observe the river condition. The numbers in parentheses are thescales. Choose the most appropriate scale.
Abundant flow (3)Some flow (2)No flow (1)-7-1. Natural stateCondition of the riverbank
Does the riverbank look natural?

Observe how much of the riverbank is natural and how much is covered with concrete.
Bank protection functions to make the riverbank stronger against floods. It also has an importantfunction for the lives of plants and animals and the relationship between people and the river.
Natural (3)Restored, but looks natural (2)Restored with much concrete (1)-8-1. Natural stateCan fish go upstream?
Are there any obstacles? Are there fish ladders?

If there are weirs or man-made structures in the river, fish or another aquatic animals cannot go
upstream freely. Observe man-made structures that obstruct the movement of aquatic animals.
Fish can go upstream (3)There are some devices such as fish ladders (2)How can I go upstream?

Fish cannot go upstream due to obstacles (1)-9-2. Rich in plants and animals
Observe whether there are many living things in the river and its surroundings and whether it isbiologically diverse. The following are four separate indicators to investigate.
-Are plants growing on the sides of the river and along the riverbank?

-Are there birds?

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Are there fish?

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Are there living things on the bottom of the river?

*For “habitats,” see the columns on the following pages.

Scale

3

Question-2

1

Are plants growing on

AbundantPlants are here

thevariety of plants

and there

Many waterNot many birds

No birds orbirds and birdor habitats

habitats

Many fish andNot many fish

No fish orfish habitatsor habitats

habitats

Are there living things on

Sand andThe surfaces ofThe bottom of

the bottom of the river?

stones arestones are

the river looks

slightly coveredslimy in thedark, and nowith algae.

presence ofalgae or insects

Insects can be

many algae.

can be found.

riversideandNo plants

riverbank?
-Are there birds?

habitats-

Are there fish?

found.

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Reasons for yourchoiceWhat is a habitat for living things?
 What is a habitat?
It is a home for living things, and a place
to live.
 What is the habitat for?
What do you do in your home?
We eat meals, sleep, and have fun.
Where in the river do fish eat meals andrest?
How about birds in the river?
How aboutriverbed?

smallorganisms

intheA habitat is an important place forliving things.

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Let’s find habitats!


Where are fish habitats?
Behind stones where fish can findfoods, such as algae and insects In
the water plants where they can hide

Where is a habitat for small organisms in theriverbed?
On the underside of pebbles and in waterplants
Let’s turn the pebbles in the riverbed upside
down. Do you find small insects?

Where are bird habitats?
In the river where they can find foods, suchas insects, fish, and water plants
In water plants and grass or on trees where
they can sleep or make nests- 12 -

2. Rich in plants and animals
Plants along the riverside
Are plants growing along the riverside?

Investigate the plants on the side of the river. Rich plants provide a place for many animals to live.
Observe the condition of the plants along the riverside and the riverbank at the investigation site.
Abundant variety of plants (3)Plants are here and there (2)No plants (1)- 13 -