The Zonguldak Drinking Water Tunnel and Canal (Doğan Regulator and Diversion Tunnel) project, completed in 2010 in order to meet the long-term drinking water needs of the city, includes a 24 m wide and 3.5 m high Doğan regulator located in the Hörgüç stream within the borders of Zonguldak province under the 23rd Regional Directorate of State Hydraulic Works and a horseshoe-shaped tunnel with a length of 2542.45 m and a diameter of 3 m, tunnel exit engineering structures, 3390 m long, 7 m wide regulator access road and 7 m wide, 566 m long tunnel exit and access roads to the surrounding villages.