Malmerspach

Malmerspach is a commune in the Haut-Rhin department in Grand Est in north-eastern France.

Located between the cantonal capital of Saint-Amarin (1 km) and the district capital of Thann (8 km), in the Thur Valley.

It is one of the 188 communes of the Ballons des Vosges Nature Park.

The commune is located in the Rhine watershed within the Rhine-Meuse basin. It is drained by the Thur River.

The Thur River, 53 km long, rises in the commune of Wildenstein and flows into the Ill River at Ensisheim, after crossing 20 communes. The hydrological characteristics of the Thur River are provided by the hydrological station located in the commune of Willer-sur-Thur. The average monthly flow rate is 5.12 m3/s. The maximum average daily flow rate is 112 m3/s, reached during the flood of April 9, 1983. The maximum instantaneous flow rate is 137 m3/s, reached on the same day.

The municipal territory is covered by the "Thur" Water Development and Management Plan (SAGE). This planning document concerns the Thur watershed. This area covers 544 km². The perimeter was established on March 4, 1996, and the SAGE itself was approved on May 14, 2001. The structure responsible for its development and implementation is the Haut-Rhin Departmental Directorate of Agriculture and Forestry.

Watercourse quality can be consulted on a dedicated website managed by the water agencies and the French Agency for Biodiversity.

As of January 1, 2024, Malmerspach is categorized as a small town, according to the new seven-level municipal density scale defined by INSEE in 2022. It belongs to the Saint-Amarin urban unit, an intra-departmental agglomeration comprising nine communes, of which it is a suburban commune. Furthermore, the commune is part of the Mulhouse catchment area, of which it is a peripheral municipality. This area, which includes 132 municipalities, is categorized as having a population between 200,000 and 700,000.