Water law permit - geothermal probe/ geothermal collector

Description of the course

Geothermal probes are generally only useful in the south of Munich. The quaternary gravel layers here are very thick. The maximum possible drilling depths in Solln, Forstenried, Harlaching, Perlach and Trudering are around 30 to 35 metres.

Geothermal collectors and baskets require less depth but a larger area and are therefore only possible on large plots of land.

• Surface collectors require about twice the living space. The pipes are laid horizontally in the ground at a depth of around 1.2 to 1.5 metres. They extract the stored solar and geothermal heat from the ground.
• Approximately one geothermal basket is required per 10 square metres of living space (with good insulation). The drilling depth per basket is approximately three to five metres, with a diameter of usually 1 to 1.2 metres.

Required documents

For projects up to and including 50 kilowatts of power, the use of near-surface groundwater and outside water protection areas and areas entered in the register of contaminated sites:

• informal letter of application
• Expert opinion from a private water management expert specialising in geothermal probes or "thermal utilisation - closed systems" (in triplicate and also in digital form).

For all other projects: All documents are required in paper form in triplicate and also in digital form.

Information on the basis of the form and

• Application form
• Explanation of the project:
  • Type of geothermal energy utilisation (probe/collector)
  • Purpose of the project (mode of operation/heat transfer medium)
  • Construction drawing and number of probes, area required for the collectors
  • Material and size of the probes/collectors
  • working/refrigerant used with proof that the brine fluid is harmless (maximum water hazard class 1), safety equipment, pipework
• Impact of the projectIntended sealing or installation (for grouting probes with ready-mixes: Declaration of no objection from the manufacturer)
• General site plan (M= 1:25,000) with marking of the location
• Site plan (detailed site plan M= 1:5,000 or M = 1:1,000) with entry of the drilling points or loops
• Layer index and development plan
  • List of strata according to DIN 4022
  • drawing of the drilling profiles in accordance with DIN 4023
  • scale plans of the boreholes
• Hydrogeological information (groundwater conditions)
  • the highest groundwater level in metres above mean sea level (MSL)
  • the average groundwater level in metres above mean sea level (MSL)
  • Location of the groundwater dam
• Further informationCertificate in accordance with DVGW 120 or "Seal of quality for geothermal probes"

Legal basis

§§ Sections 8 to 15 of the Federal Water Act (WHG)
Article 15 and Article 70 of the Bavarian Water Act (BayWG)