The reservoir is technically a flood-control dam built to contain the volatile waters of the Mšenský Potok.
The masonry dam wall is designed in a curved shape to distribute water pressure evenly across the structure.
The reservoir's total water capacity is approximately 2.3 million cubic meters.
Local infrastructure includes a specialized children's wading area that utilizes filtered water from the reservoir.
The construction project required the clearing of the former Grünwald village, which was partially flooded to create the basin.
The Mšeno Reservoir, locally known as Grünwald, is the largest urban water reservoir in the Czech Republic, situated directly within the city limits of Jablonec nad Nisou. Spanning 44 hectares, the reservoir was constructed between 1906 and 1909 to protect the town from recurring flooding. The area features three distinct sandy beaches—Slunečná, U Prutu, and Břízky—that cater to swimmers and sunbathers. The surrounding shoreline is equipped with public sports facilities, including beach volleyball courts and boat rental services. Visitors can walk the complete perimeter of the reservoir on a paved trail measuring approximately 3.5 kilometers. During winter months, the area serves as a primary access point for cross-country skiing tracks that connect to the Jizera Mountains. The reservoir is fed by the Mšenský Potok stream and serves as a vital recreational hub for residents. It is legally classified as a water structure under the management of the Povodí Labe state enterprise.
The elevated path on the dam's retaining wall providing a full panoramic view of the water and the surrounding Jizera Mountains.
Bring water shoes, as the bottom can be uneven in some entry points.
Use the trail on the side near the Břízky sports complex for the most scenic forested views.
Visit the dedicated snack kiosks located near the main beaches for local refreshments.
Avoid swimming near the main concrete dam wall and the water intake structures for safety reasons.
The reservoir is publicly accessible year-round, though swimming infrastructure is only active during the summer season.
Public nudity is strictly prohibited; swimwear is required on all beach areas.
