Buch flood retention basin

Buch flood retention basin
	Aerial view from the southeast
Location:	Ostalbkreis
Tributaries:	Chasing
Larger places nearby:	Ellwangen
	Baden-Wuerttemberg , Germany
Coordinates	48 ° 54 '34 " N , 10 ° 9' 12" E Coordinates: 48 ° 54 '34 " N , 10 ° 9' 12" E
	Data on the structure
Construction time:	1975-1981
Height above valley floor:	9.8 m
Height above foundation level :	15 m
Building volume:	61 000 m³
Crown length:	200 (or 240) m
Crown width:	7 m
	Data on the reservoir
Altitude (at congestion destination )	449.7 m
Water surface	28 ha
Storage space	1.07 million m³
Total storage space :	1.15 (or 1.36) million m³
Catchment area	81 (or 84) km²
Design flood :	86.6 m³ / s

Recreational use in summer (in the background Kapfenburg Castle )

The detention basin book (also Bucher dam or reservoir Rainau book ) at Rainau -Buch is a 1982 put into use detention basin of water board Upper Jagst; the reservoir also serves as a recreation area. It is located approx. 4 km from Ellwangen in Baden-Württemberg in the Ostalb district and is the largest lake in the Ellwang Lake District.

The Jagst , a tributary of the Neckar, is dammed . The reservoir is also used to regulate the water at low tide. If the Jagst carries less than 20 liters per second, it is lifted by water from the reservoir.

The dam is an earth dam with a clay core. Its water side is covered with concrete slabs. In summer, 0.68 million m³ are dammed in the basin. This is more than in winter, because in summer you want to use the water surface (then 25.8 ha) and in winter you need a larger flood reservoir.

(Different information about the data in the table has its origin in different sources.)

Recreation room

In the summer, a wide range of recreational uses are possible: there is a pedal boat and rowing boat rental, berths for sailing boats, you can surf and sail, swim and lie on the sandy beach, and you can also fish. There is a circular hiking trail on which you can walk around the lake in around 45 minutes.

The remains of the Buch fort of the Upper German-Raetian Limes can be seen in the bank area .

Energy generation

Founded in 1994 by the Friends of Wind and Hydropower Ostalb, the construction of a small hydropower plant began in 1995 and the inlet piece and shut-off valve were installed as part of a reservoir drainage at the end of the year. In the spring of 1996, the pipelines were laid and the rest of the work after the construction of the machine house and the installation of the turbine, as well as the drive and electrical engineering, were completed.

Technical data of the system:

Cross-flow turbine with the following technical data:

Gradient, gross summer: 7 m
Gradient winter gross: 4 m
Ingestion capacity Q: 700 l / s or 500 l / s
Nominal speed: 241 / min or 181 / min
Run-through speed: approx. 1.8 times
Efficiency: approx. 80%
Mechanical nominal power: 30 kW or 12 kW
Electrical power: 25 kW or 10.5 kW

generator

Asynchronous generator: 6/8-pole
Nominal power: 17/23 kW
Efficiency: approx. 88% at nominal power

Switchgear and turbine adjustment device

Asynchronous control system for a two-valve cross-flow turbine, with programmable control in accordance with the parallel operation regulations of the utility companies,

With network monitoring, two-stage speed monitoring, monitoring of the generator temperature and the hydraulic unit.

Turbine adjustment device consisting of: Micro hydraulic unit with 10 liter tank volume, 0.5 kW, with separate control blocks for controlling three single-acting cylinders.

Nature reserve

The retention basin located in the southeastern part (also: retention basin, pre-basin) as well as its bank zones and Jagsteinlauf have been designated as a nature reserve "Vorbecken Buch" (protection area number 1166) since July 30, 1990 by ordinance of the Stuttgart regional council . The area has an area of 11.2 hectares. The NSG was gradually expanded through the acquisition of surrounding meadow areas, which culminated in 1999 with the excavation of pools and periodically water-bearing meadows of different depths.

The area is mainly intended to serve as breeding, migration and wintering quarters for birds and fulfills this purpose impressively. Species that were previously not found there can now be observed with great regularity.

The number and variety of breeding birds is also of supraregional importance. For years, lapwing ( Vanellus vanellus ) and little ringed plover ( Charadrius dubius ) have been a permanent part of breeding birds.

Since the silting, the area has been frequented and heavily frequented by migratory birds , including Limikolen (waders) in the autumn and spring . More than 20 different species of Limikolen have already been identified, including rare species such as the Temminck sandpiper ( Calidris temminckii ), the Thor's grouse ( Phalaropus lobatus ) or the pond sandpiper ( Tringa stagnatilis ).

The Buch reservoir is also an important pillar in the region as a wintering area: Goosander ( Mergus merganser ), tufted duck ( Aythya fuligula ), pochard ( Aythya ferina ), teal ( Anas crecca ), shoveler ( Anas clypeata ), pintail ( Anas acuta ), Wigeon ( Anas penelope ), Gadwall ( Anas strepera ), mallard ( Anas plathyrynchos ) and Goldeneye ( Bucephala clangula ) are represented on a regular basis.

literature

Wolfgang Maier: The Schwabsberg basin and book of the water association Obere Jagst . In: Wasserwirtschaft 90, 9/2000.

Web links

Commons : flood retention basin book - collection of images, videos and audio files

Rainau leisure information
Profile of the nature reserve in the LUBW's list of protected areas