Introduction: How we started our GREEN interdisciplinary project education

In 1988 a seminar was held in our school by the representatives of GREEN, to demonstrate this method to the teachers of the Hungarian secondary schools dealing with water management. After this outstanding event the engineer-teachers of our schools started to find the way how to adopt the GREEN method into the curriculum of our school. We realised that this programme fits into the second year's curriculum since we teach them the water quality parameters in a whole day laboratory practice from September to January but absolutely separately from each others. By the help of the GREEN method our students could get an overview of a water course and they could use their knowledge in a complex way in the real life. That's why we built this programme into the curriculum as the beginning of the second semester. Of course, the measurements depend on the weather condition. In 1994 we started the biological investigation of the Rinya Creek.

In addition, during the computer science lessons they processed the data. The Field Manual was used in English lessons because it is absolutely perfect for our bilingual (Hungarian - English) professional language education, as well. This was the absolute beginning of the Hungarian translation of the Field Manual because the students' translation practice were taken from the Field Manual. In 1993 my class took part in the GREEN cross-cultural programme: we had a partner school in Detroit. My students could practice their everyday and professional English in this programme. Our school is absolutely statisfied with this interdisciplinary programme (Environmental Science - Computer Science - Biology and English lessons are involved) and we promote it everywhere. In Hungary we had to face a serious problem: because of the lack of the Hungarian version of the Manual most of the schools gave up this programme because the everyday use of an American book exceeded the capacity of a normal secondary school. However, we succcesfully introduced this project to our Finnish, English and Dutch sisterschools. This project will be the basis of our new partnership with the Swedish Naturbruksgymnasiet.

That time one of the biggest problem was the lack of the test kits in Hungary. In 1989 the MERCK company opened an office in Budapest and we had possibility to try their tests.

In September 1991 we organized a group of students for monitoring water quality according to the GREEN method. In the first four months we studied how to measure the parameters, and we chose Rinya Creek that flows through our town. The measurements started in February 1992.

However, we had to make some significant changes:

1. As we did not have a safe method for measuring fecal coliform secondary school students, and we also were not allowed to measure this parameter in the school, we left out this from the measurements. Therefore we proportionally increased the other eight weighting factors.

2. Since the kits listed in Appendix A of the GREEN Field Manual are not available in Hungary we use kits for rapid determination purchased by the German Merck company (Aquamerck, Mickroquant, Aquaquant, Merckoquant) and its photometer SQ118. We are absolutely satisfied with these products and highly recommend them to everybody.

Instruments used for determination of the water quality indexes:

1. Dissolved oxygen - Aquamerck Oxygen 1.11107

2. pH - Aquamerck 1.11101 test kit and Merck test strips

3. BOD5 - Aquamerck Oxygen 1.11149 measuring according to the GREEN

4. Temperature - normal thermometer

5. Total Phosphorus - Mickroquant (PMB) 14846 - Aquaquant (PMB) 14445 on site

- Merck SQ 118 photometer in the lab for control

6. Nitrate - Merckoquant 10020 test strips

- Mickroquant 14771

- Merck SQ 118 photometer in the laboratory

7. Turbidity - Secchi-disc, Merck SQ 118 photometer

8. Total solids - oven and analytical balance according to GREEN
 

Organization of measurements

Our aim was to monitor the water quality of Rinya Creek flowing through our town during the school time as I mentioned above. At the same time we wanted to measure the creek from its beginning to its recipient in order to provide data for the authorities. We are convinced that if the students know their results will be sent to the authorities they will feel responsibilty. This fact is much higher motivation than good marks.

After some field trips we chose 8 representative sampling places along the creek. This way we can create the water quality profile section of the creek. These sampling places can be easily reached by car and they cannot be missed.

We realized that by choosing appropriate sampling places the time of measurement can be dramatically reduced. A properly prepared measurement of this 23.5 km long creek (the previous day all the instruments and sampling bottles, should be packed together and the tasks should be precisely given to the students) takes about 4 hours! It is very important because a complete measurement can be finished during the day of field practice. (At our school every class has a full day of field practice every week.) The sampling points can be seen on the map.

Usually two groups of four students and one teacher carry out the measurement. One of the groups moves by car to the farthest sampling point (No.8) and comes back towards the northern end of the town (No.4). The other group walks to the sampling places No. 1-3, located in the town. Between 1992-95 the students of the second forms (aged 16) measured the creek but in 1996 the third forms will carry out the measurements due to some changes in the curriculum.

After returning to the school we start to measure the solid content of samples and put the bottles of BOD5 to a dark place. We always check the results of nitrate and phosphate measurement by photometer in the lab. So, before leving the school the students have got all the results - of course except the solid content and BOD5 - so they can leave the school with a positive feeling.

Next day after the school some students measure the solid content, and four days later during a chemistry or other science lesson the students measure the BOD5 and calculate the WQI.

Data processing

We use IBM PC for recording and processing data of the measurement at computer science lessons. At the beginning we used the Famework programme, but know we use Word for Windows and Excel.

We plot the Overall Water Quality Index along Rinya Creek. This curve shows the change of the water quality along the creek. We also plot every parameter individually because this method is very visual, and this way the students can easily realize which parameters influence highly the Overall Water Quality Index.
 

Rinya is a 23.8 km long creek, located on the left bank of Dráva River. The area of the catchment is approximately 150 km2, which contains seven urban areas (with approx. 20.000 inhabitants), among these Barcs is the biggest with its 10.000 inhabitants.

A large part of the catchment is used for agricultural cultivation.

The average discharge of the creek is 80 l/s. This creek is one of the biggest water course of the planned Danube-Dráva National Park.

The sources of pollution in the catchment area:

Point sources : - the sewage treatment plant of Barcs (No.1),

- the rainfall sewers,

- the pump station which in case of emergency directly releases the raw sewage into the creek (No.2.)

- pig farm of Drávaszentes (No.4-5),

- the illegal sewage disposal of the urban areas along the creek.

Nonpoint sources : - agricultural runoff of chemicals,

- soil erosion,

- natural organic wastes (e.g. leaves).

From the changes of the water quality we can state that in the lower part of the creek (approx. 6 km ) the point source pollutions have significant effect on the water quality: at the sampling point No.1 the sewage treatment plant of Barcs, and at No.4 the Györgyös Creek. The sewage treatment plant of Barcs does not use any tertiary treatment. The Györgyös Creek flows through the second biggest urban area, Csokonyavisonta, which does not have any sewage treatment facilities, and this creek also transports the sewage of the pig farm of Drávaszentes.

It is very important to realise that before the Györgyös Creek, the biggest tributary of Rinya reaches the Rinya Creek (sampling point No.5) only about 2000 people have effect on the Rinya Creek. But from this point about 18.000 people live on these two creeks.

So, after four years of investigations we can state that the quality of the creek above the Györgyös Creek (sampling point No.5) is fairly good, sometimes excellent due to the increasing price of chemicals in Hungary... The biological monitoring also proved the good quality.

We have problems with the quality of Rinya Creek in the last 6 km. The water quality, in addition to the discussed point sources, depends mainly on the following variables:

the rate of the discharges of Rinya and Györgyös Creek

the amount of rainfall in Barcs

the rate of the discharges of Rinya Creek and the effluent of wastewater treatment plant.

the proper operation of the pump station

By analysing the results we can clearly see that the following paramaters have very strong effects on the water quality:

- Dissolved Oxygen

- BOD5

- Phosphorous content

- NO3 content

Our conclusions:

a. From these results it can be clearly seen that urban areas have significant effects on the creek. The pollution could be minimalizied if the sewage treatment plants used some tertiary treatment system to remove phosphorus and nitrogen.

b. We suggested the pigfarm that they should treat their sewage. (In 1993 the pigfarm of Drávaszentes started to use some mechanical treatment. In addition, the liquid wastes are used for irrigation in some periods of the year.)

Afterwords

In 1995 our school prepared the complete Hungarian version of the Field Manual for the environmental secondary schools upon the request of the Ministry of Labour, that is responsible for the professional education in Hungary. This year the second edition is coming out.

In 1992 two of my students, Szabolcs Rózsa and István Récsei won the first prize of the national competition organized by the Hungarian Hydrological Association with a study titled "The investigation of Rinya Creek according to the GREEN method".

In the last two years our school in cooperation with the Nature Conservation Office started to monitor two other water courses in a protected area.

In 1994 one of our colleagues, István Vajda made a diploma work for environmental engineering by using the GREEN method.

Upon our experiences we are absolutely convinced that the GREEN method is suitable not only for education but also for monitoring of water courses by schools or civil organizations.