The Westpark is located in the west of Aachen, bordered by Gartenstraße, Welkenrather Straße, Weststraße and Vaalser Straße.
A committee led by Emil Lochner, an Aachen textile manufacturer, bought the cherry orchards in front of the Junkerstor in 1882. The Lochnergarten was laid out there in 1885, replacing the magnificent English garden at the Lochner villa between Lochnerstraße and Karlsgraben. In the same year, the zoological garden Aachen was opened there under the management of the textile manufacturer Lochner, which housed around 50 giant snakes, bears and tigers as well as numerous native animal species.
The construction of the park was partly financed by shares. As early as 1882, a glass palace, a large, round hall with many adjoining rooms whose walls were made of glass, was built next to the beautiful parks. This palace could hold up to 3,000 visitors.
Around 1901, there was a cycling track in what was then Lochnerpark, where five students and six pupils from the Alemannia soccer club (now Alemannia Aachen) held their training sessions with the ball. In 1908, the year the racecourse was closed, the Aachen cycling club Zugvogel 09 also held its first training sessions here.
In 1905, the park was temporarily closed because the feeding and transportation costs for the animals in the zoological garden had been underestimated.
During the First World War, a military hospital and convalescent home for soldiers was set up in the park's glass palace, but it was completely destroyed by a major fire in 1917. The Westpark was revived when it was reopened on May 23, 1920 and from then on bore the name Westpark. Two years later, in 1922, a new but much smaller glass palace was opened on the site.
As early as 1935, it was once again possible to go boating on the park's pond. An animal park was added in the same year. In the years before and during the Second World War between 1935 and 1944, it was called the Aachen Animal and Plant Garden. Most of the animals were killed in a bombing raid in 1944.
After the end of the Second World War, all other buildings in the Westpark were demolished. From the time of the zoo, only a pond at the exit to Gartenstraße remains to this day.
Today, most people from the west of Aachen use the Westpark for recreation. There is a kindergarten right next to the Westpark pond.
The total water surface area was determined to be 7,250 m². The Westparkweiher is 170 m long, up to 66 m wide and a maximum of 1.60 m deep. This results in a volume of 9,425 m³.
The catchment area only includes the immediate surroundings of the pond. Therefore, there is no flood inflow or flood outflow. The dam is operated via a spillway. The gate valve for the bottom outlet is also located in this structure.
The dry weather discharge of the dam is routed to the overflow of the spillway. The height of the permanent water level target(full water level = Zv) is approx. 184.54 m above sea level.
The estimate is based on the height of the drainage shaft with a cover height of 185.02 m above sea level and a shaft bottom of 182.94 m above sea level.
The reservoir targets for ZH1 and ZH2 do not exist due to the lack of flood discharge, as there is no dam structure due to the burial in the subsoil and therefore no investigations in accordance with DIN 19700 are required.
The overflow or outlet of the dam is into a DN 300 concrete pipe with discharge into the piped Johannisbach.
The Westparkweiher pond is fed via the so-called market water pipeline. Since the 17th century, this has been a spring water drain in the area of Vaalser Straße / Gemmenicher Weg. There are several springs in this area that are contained in pits. The free overflow of these springs is collected in the market pipeline. In earlier times, the market pipeline was connected to the Krämer pipeline in the Lochnerstraße area and was used to supply Aachen's city center with well water.