Editing Lake Constance (section)

=== Tributaries ===
[[File:Aerial image of the mouth of the Rhine into Lake Constance.jpg|thumb|The mouth of the Alpine Rhine into Lake Constance]]
The main tributary of Lake Constance is the [[Alpine Rhine]]. The Alpine Rhine and the [[Seerhein]] do not mix greatly with the waters of the lake and flow through the lakes along courses that change relatively little. There are also numerous smaller tributaries (236 in all). The most important tributaries of the Obersee are (counterclockwise) the [[Dornbirner Ach]], [[Bregenzer Ach]], [[Leiblach]], [[Argen]], [[Schussen]], [[Rotach (Lake Constance)|Rotach]], [[Brunnisach]], [[Linzer Aach|Seefelder Aach]], [[Stockacher Aach]], [[Salmsacher Aach]], the [[Aach (Lake Constance, Arbon)|Aach near Arbon]], [[Steinach (Lake Constance)|Steinach]], [[Goldach (river)|Goldach]] and the [[Old Rhine (Fußach)|Old Rhine]]. The outflow of the Obersee is the [[Seerhein]], which in turn is the main tributary of the Untersee. The most important tributary of the Untersee is the [[Radolfzeller Aach]]. The source of the Radolfzeller Aach is the [[Aachtopf]], a [[karst spring]] whose waters mostly derive from the [[Danube Sinkhole]]. Therefore, the [[Danube]] is indirectly also a tributary of the Rhine.
{| class="wikitable sortable"
|+ The ten biggest tributaries of the Obersee by discharge volume<ref>Landesanstalt für Umwelt, Messungen und Naturschutz in Baden-Württemberg: [http://www.lubw.baden-wuerttemberg.de/servlet/is/8849/jhdt_hochwasser.pdf?command=downloadContent&filename=jhdt_hochwasser.pdf ''Informationen zum Jahrhunderthochwasser 1999.''] {{Webarchive|url=https://web.archive.org/web/20131023235412/http://www.lubw.baden-wuerttemberg.de/servlet/is/8849/jhdt_hochwasser.pdf?command=downloadContent&filename=jhdt_hochwasser.pdf |date=2013-10-23 }} (pdf; 24&nbsp;kB)</ref> with its catchment areas:<ref>Internationale Gewässerschutzkommission für den Bodensee (publ.): ''Der Bodensee. Zustand – Fakten – Perspektiven.'' IGKB, Bregenz, 2004, {{ISBN|3-902290-04-8}}, [http://www.hydra-institute.com/igkb/IGKB%201.2.pdf Kapitel 1.2] {{webarchive|url=https://web.archive.org/web/20120514054950/http://www.hydra-institute.com/igkb/IGKB%201.2.pdf |date=2012-05-14 }} (pdf; 1.2&nbsp;MB)</ref>
|-
! align="left"| River
! align="left"| Average discharge<br />[m<sup>3</sup>/s] (1978–1990)
! align="left"| Discharge<br />in %
! align="left"| [[Drainage divide|Catchment]]<br />[km<sup>2</sup>]
! align="left"| Catchment<br />in %
|-
|Alpine Rhine || align="right"| 233 || align="right"| 61.1 || align="right"| 6,119 || align="right" | 56.1
|-
|Bregenzer Ach || align="right"| 48 || align="right"| 12.6 || align="right" | 832 || align="right"| 7.6
|-
|Argen || align="right"| 19 || align="right"| 5.3 || align="right"| 656 || align="right"| 6.0
|-
|Old Rhine<br />(Rhine Valley Canal) || align="right"| 12 || align="right"| 3.1 || align="right"| 360 || align="right"| 3.3
|-
|Schussen || align="right"| 11 || align="right"| 2.9 || align="right" | 822 || align="right"| 7.5
|-
|Dornbirner Ach || align="right" | 7.0 || align="right"| 1.8 || align="right"| 196 || align="right"| 1.8
|-
|Leiblach || align="right"| 3.3 || align="right" | 0.9 || align="right"| 105 || align="right"| 1.0
|-
|Seefelder Aach || align="right"| 3.2 || align="right" | 0.8 || align="right"| 280 || align="right"| 2.6
|-
|Rotach || align="right"| 2.0 || align="right"| 0.5 || align="right"|130 || align="right"| 1.2
|-
|Stockacher Aach || align="right"| 1.6 || align="right"| 0.4 || align="right"| 221 || align="right"| 2.0
|- style="background:#EEEEEE;" class="sortbottom"
|''Sum of the<br />10 main tributaries'' || align="right" | ''340'' || align="right"| ''89.6'' || align="right"| ''9,721'' || align="right"| ''89.2''
|- style="background:#DDDDDD;" class="sortbottom"
|Total inflow || align="right"| 381 || align="right"| 100.0 || align="right" | 10,903 || align="right" | 100.0
|}<!-- <small>Empty cells mean there is no data in the publications.</small> -->

Because the Alpine Rhine brings with it [[drift (geology)|drift]] from the mountains and deposits this material as [[sedimentation|sediment]], the Bay of Bregenz will silt up in a few centuries time. The silting up of the entire Lake Constance is estimated to take another ten to twenty thousand years.