Sanna (Inn)
| Sanna | ||
 The Sanna in Pians |
||
| Data | ||
| Water code | AT : 2-8-59 | |
| location | Tyrol , Austria | |
| River system | Danube | |
| Drain over | Inn → Danube → Black Sea | |
| origin | Confluence of Rosanna and Trisanna at Tobadill 47 ° 7 ′ 2 ″ N , 10 ° 29 ′ 25 ″ E |
|
| Source height | 870 m above sea level A. | |
| muzzle | in Landeck in the Inn Coordinates: 47 ° 8 ′ 38 " N , 10 ° 33 ′ 52" E 47 ° 8 ′ 38 " N , 10 ° 33 ′ 52" E |
|
| Mouth height | 775 m above sea level A. | |
| Height difference | 95 m | |
| Bottom slope | 13 ‰ | |
| length | 7.1 km | |
| Catchment area | 727.7 km² | |
| Discharge at the Landeck-Bruggen A Eo gauge : 563.2 km² Location: 170 m above the mouth |
NNQ (07.02.1972) MNQ 1971–2010 MQ 1971–2010 Mq 1971–2010 MHQ 1971–2010 HHQ (23.08.2005) |
1.81 m³ / s 4.43 m³ / s 20 m³ / s 35.5 l / (s km²) 143 m³ / s 491 m³ / s |
| Small towns | Landeck | |
The Sanna is an approx. 7 km long left tributary of the Inn in Tyrol with the source river Rosanna approx. 49 km long .
course
The Sanna arises from the confluence of the longer Rosanna and the more watery Trisanna at Wiesberg Castle ( Tobadill municipality ). The Rosanna flows, coming from the Verwall , through the Stanzertal , the Trisanna rises in the Silvretta and flows through the Paznaun . The Sanna flows first in a north to north-easterly direction, then in an easterly direction through the lower Stanzertal and flows into the Inn at Landeck . The three towns of Pians , Grins and Landeck are located on the Sanna . In its course it takes on three larger tributaries: from the left the Lattenbach near Pians and the Mühlbach near Grins, and from the right the Flathbach near Pians.
Catchment area
The natural catchment area of the Sanna is 727.7 km². The drainage of numerous tributaries from Rosanna and Trisanna into the Silvretta reservoir and the Kops reservoir reduces the hydrologically effective catchment area by 163.8 km². Since this water is channeled across the main European watershed , the effective catchment areas of the Danube and Rhine are also reduced or enlarged by this amount.
The mean height of the catchment area is 2200 m above sea level. A. , the highest point is the southern Fluchthorn at 3399 m above sea level. A. In the catchment area of the Sanna there are 67 glaciers with a total area of 15.48 km², which corresponds to a degree of glaciation of 2.1% (as of 2002). Most of the glacier runoff is diverted into the reservoirs, however, only 19 glaciers remain under the Sanna runoff regime.
Water flow
The mean discharge at the Landeck-Bruggen gauge is 20.0 m³ / s, which corresponds to a discharge rate of 35.5 l / s · km². In relation to the undiminished catchment area, there is a natural mean discharge of the Sanna of more than 26 m³ / s. The Sanna has a nival runoff regime that is dominated by the snowmelt in the higher elevations of the catchment area. The glaciers have little influence due to the diversions. The monthly mean of the month with the highest discharge, June, is 50.8 m³ / s, around ten times that of the month with the lowest discharge, February, with 5.31 m³ / s.
Abundant rainfall in the catchment area and a high snowfall limit led to the largest recorded flood event to date in August 2005 with a maximum discharge of 491 m³ / s, more than twice the maximum value measured up to that point. While the damage in the area of the Sanna was comparatively minor, both Rosanna and Trisanna and downstream caused massive flooding ( Alpine flood 2005 ).
environment
The Sanna shows a very good to good ecological condition, in the urban area of Landeck a moderate ecological condition. The sole is only spotty, the banks are built over long stretches. The river is classified in water quality class I-II (status 2005).
use
Hydroelectric power plant
A hydropower plant with an output of approx. 83 gigawatt hours and a head of 105 meters is planned on the Sanna .
White water sports
The Sanna is a steep, heavily blocked river. For rafting and kayaking enthusiasts , the level of difficulty is therefore a lot higher than that of the Inn, despite the significantly lower water flow. Over a distance of six kilometers, short hard waves alternate non-stop with heavy breakers and rollers, while at the same time the free flow of water is inhibited by boulders and crossbars lying irregularly in the middle of the current.
In 1996 the world championship in canoe whitewater racing took place on the Sanna .
Web links
- Water level, flow and water temperature of the Sanna at the Landeck-Bruggen gauge (Hydrographischer Dienst Tirol)
- Information on navigating the river
Individual evidence
- ↑ a b c d TIRIS - Tyrolean regional planning and information system
- ↑ Land Tirol: Hydrographic characteristics
- ^ A b c Federal Ministry for Agriculture, Forestry, Environment and Water Management (ed.): Hydrographisches Jahrbuch von Österreich 2010. 118th volume. Vienna 2012, p. OG 91, PDF (12.6 MB) on bmlrt.gv.at (yearbook 2010)
- ↑ a b c State of Tyrol: The Landeck / Sanna gauge (PDF; 487 kB)
- ↑ Federal Ministry of Agriculture, Forestry, Environment and Water Management (Ed.): Flood 2005 - Event documentation of the Federal Water Management Administration, the Forestry Service for Torrent and Avalanche Control and the Hydrographic Service. Vienna 2006 ( PDF; 5.2 MB ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. )
- ↑ Federal Ministry of Agriculture, Forestry, Environment and Water Management (ed.): Saprobiological water quality of the flowing waters of Austria. As of 2005. ( PDF; 1 MB ( Memento of the original from December 22, 2015 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this note. )
- ↑ Data & figures on Wasserkraft Sanna , wasserkraft-sanna.at, accessed on October 28, 2015
