The "Regulation on Rainwater Collection, Storage, and Discharge Systems" published in the Official Gazette dated 23/06/2017 and numbered 30105 by the Ministry of Environment and Urbanization is the first regulation at the national level that includes nature-based solutions of Sponge Cities in rainwater management.

This regulation aims to regulate the procedures and principles regarding the planning, design, project design, construction, and operation of rainwater collection, storage, and discharge systems. It covers the procedures and principles related to the planning, design, project design, construction, and operation of rainwater collection, storage, and discharge systems, focusing on public health and safety, environmental protection, sustainability of the system, and protection of drinking water sources from waterborne pollution.

The regulation includes infrastructure techniques and solutions for nature-based rainwater infrastructure in an annex, under the title "storage and infiltration of rainwater," detailing infrastructure techniques and rainwater harvesting systems.

The "İzmir Metropolitan Municipality Zoning Regulation" published in the Official Gazette dated 03/06/2021 and numbered 31500 includes articles and clauses related to cisterns, rainwater tanks, rainwater harvesting systems, and green roofs.

Cisterns - Rainwater Tanks - Rainwater Harvesting Systems

Article 39 - (1) On parcels larger than 1000 m²; a drainage system is established to collect roof and ground surface waters in a cistern/rainwater tank installed underground, for use in garden irrigation, car washing, and similar activities, and if necessary, it is treated for reuse. The said drainage system and cistern/rainwater tank can be arranged within the side and rear yard setbacks behind the building front line and shown on the site plan.

(2) Rainwater pipes collecting roof water are connected to the cisterns or rainwater tanks mentioned in the first paragraph or to the rainwater network on the road; however, they cannot be connected to the sewage network. If it is determined that it is connected, the relevant authority or İZSU General Directorate intervenes, and the cost is recovered from the building owner.