City Hall Lake Marl A lake in the central context

Objective:
Development of the town hall lake as a crystallization core of the green order in the city center:
A redesign with the claim of vitalization (contemporary quality of stay), modernization (needs-based water technology) and sustainability (economic-ecological self-care) in the context of spatial-functional relationships to the other urban developments in the city center.
Task:
While it was a profoundly important decision in terms of urban culture in the 1970s to place a water area totalling around 2.2 ha in the then "new" city centre, the artificial lake system (Small Lake and Large Lake) is getting on in years and now has a very high need for renovation (groundwater wells, pressure pipelines, sealing membranes). The water quality is clearly impaired by the technically deficient but also biological processes (faecal input by fish and birds, feeding by recreationists). There is an urgent need for action to improve the situation.

Against this background, a redevelopment and development study (Pridik Freese, Marl, December 2004) has been prepared, resulting in the recommendation of Variant D "Lake restoration and design with urban integration". According to the resolution of the Council of the City of Marl (December 2005), Variant D is to be further pursued with the redesign and development of the Town Hall Lake:
-Small Lake - abandonment and deconstruction
-Large Lake - cautious reduction of the water surface/volume through necessary restoration of the geomembrane in the shore area and through necessary cleaning areas (water plants) in a ratio of 1:2 (water plants / open water area)
-maintenance of the important perception area between the lake and the city centre, taking into account the results of the competition for Creiler Platz, which is currently being prepared, and taking into account the presentation of art objects
-opening of the visual relationships to the city hall by removing woody plants, taking into account tree protection and the results of the competition for the new museum building
-creation of a new footpath connection from Josefa-Lazuga-Allee (Wohnen-West) to Sickingmühler Straße / Martin-Luther-Straße by means of a footbridge across the lake
-Abandonment and dismantling of dilapidated fixtures and fittings as well as creation of new recreational and play facilities on the shore (e.g. water playground, sunbathing lawn, etc.). e.g. water playground, lawn, beach, seating terrace (including at hotel), jetty)
-Controlled recreational use of open water area (model boats, pedal boats where appropriate. Pedal boats)
-Conceptual park maintenance - opening, clearing and rejuvenation of woody vegetation, promotion of flowering shrubs, clearing of solitary trees)
-Outcomes to be developed:
-Aquatic biology/ecology - water quality of tributaries, resilience (model) of lake water, properties/condition of sediment, stratification/quality of lake water (temperature, oxygen content, nutrient content, trophic rating), lake depth (echograph), biology (aquatic life and animal population) - Objective: economic-ecological (self-)maintenance
-Water technology - rainwater decoupling potential (technical feasibility, permitability, hydraulic and water quality requirements in the lake), hydrogeological exploration for new well system, modernization concept water technology taking into account existing plant components - Objective: Water technology as required
-Liner - mechanical load-bearing capacity (for future maintenance and construction measures), impermeability, elasticity and durability (resistance to rotting) - objective: risk reduction that can be assessed
-Open facilities - comparison of the specialist results (water ecology, water technology, liner), the framework results (among others: water quality, water quality, water quality, water quality, water quality, water quality, water quality), the framework results (among others: water quality, water quality, water quality, water quality, water quality, water quality, water quality, water quality, water quality, water quality, water quality, water quality, water quality, water quality). a. competitions) and accompanying results with the objectives and requirements of variant D - Objective: contemporary quality of stay in the context of spatial-functional relationships with the other urban developments in the city centre
Project sequence, milestones:
PROJECT STRUCTURE
-Project management - planning and environmental office
-Project control - landscape architect (project program, project participants, organization, scheduling and payment planning, project meetings, control, decision documents, project status report, documentation)
-Project monitoring - regular (1x/quarter) participation circle (residents ("Marler Stern", "Wohnen West", hotel), interest groups (youth, seniors, clubs, users), museum, politics - acceptance of the project / transparency of the processing / multiplication of the results (recording of suggestions and concerns)
-Project processing - appraisal (water ecology, hydrogeology, geomembrane), surveying (terrain heights, (terrain heights, lake depths), planning and construction supervision (outdoor facilities, water technology) - landscape architect and specialist engineers
-safety and health protection coordination
-project execution - landscaping and specialist companies
PROJECT CURRENT
-2007 (basics) - preparation of the project program, preparation of an organization and schedule plan, Research of old planning and documentation documents, selection of project participants, surveying (terrain heights, lake depths), assessment (water ecology, hydrogeology, stormwater decoupling potential, geomembrane), interim report - consequences for redesign and development
-2008 (planning focus) - Planning (outdoor facilities, water technology) and tendering 1. Construction phase (lot 1 deconstruction of the Small Lake, lot 2 restoration and rehabilitation of the Large Lake), project monitoring with participation group, start of construction of the 1st construction phase, planning and tendering of the 2nd construction phase (design of the lake environment), completion of the assessment (water ecology)
-2009 (focus of execution) - execution and completion of the 1st construction phase, start of construction of the 2nd construction phase, project monitoring with participation group, execution of the 2nd construction phase
-2010 (completion) - completion of the 2nd construction phase, "Large Lake Festival".