Storemyrvann
In 1876, Bjortjønn, Grunnevann, and Bærvann lakes were dammed. The water was carried through pipes down Spegedalen and onward via Dalane to Kvadraturen in the city centre. To increase capacity, a seven-metre-high dam was built in 1886 at the edge of the bogs that lay between Bærvann and Bjortjønn. This created Storemyrvann (“the large bog lake”).
As the city’s need for water grew, the supply was expanded in 1923 when Krogvann lake, west of Dalane, was connected to the system. From 1939 to 1956, river water from the Otra was pumped up to Storemyrvann through wooden pipes bound with iron wire. From 1956 to 1971, the water was pumped up to Bærvann through new cast-iron pipes. From there it flowed down to Storemyrvann and Bjortjønn, and then through pipes to Dalane. There it was filtered and treated with lime in a purification plant built in 1941.
From 1971, river water from the Otra was no longer pumped up to Bærvann, but the Spegedal reservoirs and Krogvann continued as reserve supplies until 1979. Rossevann was added as a drinking-water reservoir in 1969, and Tronstadvann was connected in 1979. These two lakes remain the city’s drinking-water sources today.
Bjortjønn
In 1876, Bjortjønn, Grunnevann, and Bærvann lakes were dammed. The water was carried through pipes down Spegedalen and onward via Dalane to Kvadraturen in the city centre. To increase capacity, a seven-metre-high dam was built in 1886 at the edge of the bogs that lay between Bærvann and Bjortjønn. This created Storemyrvann (“the large bog lake”).
As the city’s need for water grew, the supply was expanded in 1923 when Krogvann lake, west of Dalane, was connected to the system. From 1939 to 1956, river water from the Otra was pumped up to Storemyrvann through wooden pipes bound with iron wire. From 1956 to 1971, the water was pumped up to Bærvann through new cast-iron pipes. From there it flowed down to Storemyrvann and Bjortjønn, and then through pipes to Dalane. There it was filtered and treated with lime in a purification plant built in 1941.
From 1971, river water from the Otra was no longer pumped up to Bærvann, but the Spegedal reservoirs and Krogvann continued as reserve supplies until 1979. Rossevann was added as a drinking-water reservoir in 1969, and Tronstadvann was connected in 1979. These two lakes remain the city’s drinking-water sources today.
Bjortjønn/Storemyrvann
1876 wurden Bjortjønn, Grunnevann und Bærvann angestaut. Das Wasser wurde in Rohren durch Spegedalen und weiter über Dalane nach Kvadraturen geleitet. Um die Kapazität zu erhöhen, wurde 1886 ein 7 m hoher Damm am Rand der Moore zwischen Bærvann und Bjortjønn gebaut. So entstand Storemyrvann.
Der Wasserbedarf der Stadt stieg, und 1923 wurde das Wasser aus Krogvann auf der Westseite von Dalane angeschlossen. Von 1939 bis 1956 wurde Flusswasser von einem Pumpwerk bei Otra in einem Rohr aus Holz, mit Eisendraht umwickelt, nach Storemyrvann gepumpt. Von 1956 bis 1971 wurde das Wasser in neuen Gussrohren nach Bærvann gepumpt. Von dort floss es nach Storemyrvann und Bjortjønn und in Rohren nach Dalane. Dort wurde es in einer 1941 errichteten Anlage gereinigt und gekalkt.
Seit 1971 wurde Flusswasser aus Otra nicht mehr nach Bærvann gepumpt, aber die Spegedalsbassengene und Krogvann blieben bis 1979 Reserve. Rossevann wurde 1969 als Trinkwasserspeicher hinzugefügt und Tronstadvann 1979 angeschlossen. Diese beiden Seen sind heute die Trinkwasserquellen der Stadt.