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Thursday, January 26, 2012

Outdoor study

Establishment and usage of Kehtna water reservoir

Kehtna  water reservoir, also known as Räägu reservoir lies 58 54' N; 24 52' E. It is 57,5 m above sea level. The water resrvoir was created on the River Kuusiku ( lenght 20.9 km ) which begins at the border of the villages Palasi and Ohekatku and flows into the River Vigala. On the shore by the dam there is a stone showing the year of completion and a small sheltered sitting area. 

In 1970 Kehtna sovkhoz built a dam on the River Kuusiku. Originally the water reservoir was built there to pump water for watering the local pastures. Across the road there used to be mobile watering systems on big wheels where electrical pumps were used. Next to the reservoir there was a power substation which gave power for the pumps in 70s-80s. Thanks to the watering system, it was possible to make hay 4 times a summer and produce animal feed which was used for feeding local Kehtna sovkhoz cattle. The water reservoir has been used for swimming. Nowadays it is used for swimming and fishing too. Midsummer Day's bonfires are also lit there.

Text translated by Kaarel-Eerik.

KIK - slide show


On our study day we found leeches, mudsnails and other species of  snails, arachnids, larvae of Mayflies (Ephemeroptera) and its imagos, larvae of dragonflies similar to Aeshna mixta  and of those similar to damselflies. Also larvae of Gyrinus sp, types of Dytiscidae  and species of Trichoptera, toads and their tadpoles. 

Speed of the water  flow
On our outdoor study we found out that the speed of the water flow was 0.7 mps (meters per second). We used the Winkler method  and VISCOLOR HE OXYGEN SA 10 kit. We measured the content of oxygen  on that spring day which was 8.4mg/l and on an autumn day 8.0mg/l.

Water limpidity

We measured that the water limpidity was 0.5 – 1.5 m.

Water colour

The water can be described as  yellowish.

Water pH value

Water pH value was 6-7 by using  indicator paper. 

The summary was translated by Sten.

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Partner schools

ESTONIA: Kehtna Primary School is situated in the village of 1,200. There are no big towns nearby, although the capital Tallinn is just 60km to the north. We are surrounded by forests, bogs, farmland and therefore paying extra attention to nature studies and the environment is important to us. We are a school of the Green Flag and a Health-Concious school. There are 155 students and 20 teachers in our school. Students are aged 7-17.

ITALY: Liceo Classico "Megara" con sezione scientifica annessa is a secondary school for students aged 14-19. It mainly offers three different courses for classical, scientific and social science studies. The school mainly serves students from Augusta. Our school is located in a very important area for its nature, history, archaeology and tourism. Our suburban town of Augusta is very near to Siracusa, one of the oldest and most important Greek colonies in Sicily. Our students are all members of "Legambiente" which is a national leading environmental organization which offers educational programs in schools. We live by the sea and our area is very rich in waterways, rivers and ponds.

FRANCE: College Claude Bernard is in a suburban city (Grand-Quevilly) with about 30,000 inhabitants. A town with 400,000 people called Rouen is near to us. The area has little industry nowadays following the closure of the chemical factories and the Renault car plant.

TURKEY: Tepeköy Ilkögretim Okulu is a public school serving children aged 7-15, starting from pre-school till the 8th grade. It is a rural school and caters for 226 students and 18 teachers. Our school is in Nevsehir (Cappadocia Region), being situated in agricultural region. Our region does not have sufficient water resources and we need to focus on environmentally-friendly options.

SPAIN: IES Concepcion Arenal is a secondary education centre located in Ferrol, a town with 70,000 inhabitants in the region of Galicia (north-west of Spain). There are 85 teachers and 700 students in compulsory (12-16 years old), post-compulsory (16-18 years) part and in vocational training.