Tulare Lake

36.066666666667 - 119.75083333333Koordinaten: 36 ° 4 ' N, 119 ° 45' W

The Tulare Lake was a lake in the southern San Joaquin Valley in what is now Kings County in California. Until the late 19th century, he was the face after the second largest fresh water lake (after Lake Michigan ), which lay entirely in the United States. As his feeds more and more water was withdrawn for growing cities and for irrigation of agricultural land, he dried up. Its name derives from tule rush off, the English name of Schoenoplectus acutus Teichbinsenart that grew on its marshy banks, and is the namesake of the Tulare County was carved out of the Kings County in 1893.

Geography

The lake was part of a partially endorheischen basin at the southern end of the San Joaquin Valley, which makes up with around 42,000 sq km area about ten percent of the area of California and is located between the Sierra Nevada to the east, and the California coastal mountains to the west. He lay in a created by tectonic subsidence landscape, which has only little differences in height by river deposits and is separated by alluvial fan of the Kings River and the Los Gatos Creek from the northern San Joaquin Valley. The Tulare Lake was the largest terminal lake in the basin, the other three - core Lake, Buena Vista Lake and Goose Lake - together had not even a tenth of its surface.

Due to the small differences in altitude lake area fluctuated greatly depending on the season or dry periods. In years with average rainfall, the water level rose by one meter in precipitation years by up to three meters. The wide belt of reeds and marsh were flooded by the lake. Exceeded the water level a height of 63 m, the lake could reverse the flow direction of the Fresno Slough, a 64 kilometers long and up to 76 meters wide, marshy, natural channel at the north end of the lake, and discharge its water into the San Joaquin River. This happened 1850-1878 in 19 of 29. At its highest water level at 66 m in the years 1862 and 1868, the lake had an area of ​​2,000 km ² and was about 10 feet deep. The discharge rate in 1862 is estimated at about 220 million cubic meters of water. In dry years, the shallow lake was much smaller. The highly variable shorelines could be moved by strong winds by several kilometers.

Depending on Climate Change swayed the surface of the lake during the Holocene several times between a few up to its maximum size of over 2,000 km ². It is believed that the lake in the dry periods 892-1112 and 1209-1350 must have been either dried up or at least very small. Only the rising temperatures and rainfall since the mid-19th century were frequently overrun the lake. Without that began in the 1860s, diversion of rivers and increased water extraction of the Tulare Lake would probably have drained in the 20th century in 40% of years in the San Joaquin River.

Inflows

The four main tributaries of the Tulare Lake were all from the Sierra Nevada and formed in the plane wide inland delta with numerous canals and wetlands that could become dry at times. In the south of the Kern River created below Bakersfield a clearly defined sump level, leaving the bulk of its water in the core and Lake Buena Vista Lake, a smaller part flowed on to the Tulare Lake. The north adjoining river systems of White River and Deer Creek led to little water to run over most of the year to Tulare Lake, which happened only at high tide. The Tule River, the smallest inlet to the lake, formed from Porterville an alluvial fan, which he regularly flooded at high tide because of its small estuaries. In the northwest of the Kaweah River resulted in Visalia in the plane and was divided into four large and numerous small channels, which led to extensive wetlands. Northernmost and most important tributary with something half the water supplied was the Kings River with its large alluvial fan that separated the valley on its eastern side of the San Joaquin River. Most of his water flowed through elongated wetlands toward Tulare Lake, while a smaller amount to the San Joaquin River was conducted. From the westerly, dry coastal chain no river reached the sea.

The region in which lay the lake, a climate similar to the Mediterranean, so that 80 percent of the rainfall with an annual average total of less than 400 mm from November to March fall, of which three-quarters evaporate again. 98 percent of the surface water in the basin originate from the Sierra Nevada, mainly from the period of snowmelt from April to July, and the remaining two percent of the coastal range.

The end of the lake

On the shores of Tulare Lake Yokut the Indians, who brought it because of the game and fish wealth of the area to the highest population density in North America in the pre- colonial period, the ecosystem of the lake but did not bother to live. The arrival of Europeans and the introduction of agriculture in the second half of the 19th century marked the beginning of the comprehensive transformation of the region. The flood of 1861 /62 that changed greatly the drainage paths of flows, and the flood of 1867/68, the highest since the arrival of the Europeans, led for the last time to the maximum extent of the lake. Already in 1871 were large areas of agricultural land, the numerous estuaries of the four rivers, particularly the Tule River and the Kaweah River, were converted into irrigation canals. 1872 Kings River was diverted entirely to the San Joaquin River, causing the water level of the Tulare Lake as far declined that as early as the 1880s, parts of the original lake bottom could be used for agriculture. At the same time, the salinity of the lake rose so strong that many fish species could no longer survive. 1899, the lake is the first time described as dried out, the end of the fishing was reached.

Although until the second half of the 20th century at the headwaters of the rivers more and more dams were built for irrigation of agricultural land, and for drinking water supply, originated in precipitation years always larger water surfaces, von 1906 until 1917. Subsequent drought dropped the lake again shrink. In the 1920s, James Griffin Boswell bought from Georgia 200 km ² of the former lake bed to plant cotton on it. His eponymous nephew, who enlarged the property to around 650 km ² in California alone, and thus became the largest cotton producers in the country, finally put the remains of the lake dry.

In the years 1937-1946 and 1950-1953 the lake was formed again, as the irrigation and drainage channels, the accumulated amounts of water could no longer pay. So it could be used for flying boats during the Second World War as a by- airfield the Naval Air Station Alameda.

In the 20th century, four so-called storage cells in an area of ​​80 km ² established mainly in the southern part of the valley, to accommodate high water. These areas are bounded by levees and are no longer used for agriculture. The levees broke in the particularly heavy flooding in 1969, 1983 and most recently in 1997. 1969, this 360 km ² of land flooded and the newly formed Tulare Lake reached with a water level of 58.6 meters, the highest level in this century. 1983 surpassed the flood plains as 400 km ², but the lake did not reach again the water level of 1969. In both cases, pumping the water took longer than a year.

There are plans to restore at least a portion of Tulare brine. This could accommodate future flood and at the same time, serve as water storage for dry years in the San Joaquin Valley, the world's most productive agricultural region. 2001 has one of the largest growers of cotton ceased production in the Tulare Basin due to sharp decline in world market prices and renatured in cooperation with the State of California a small portion of its acreage to a wetland.