| Håøya | Agder, Norway | 8 | 1 | 0 | 1994-11-04 | |
| Ibestadvatnet | Troms, Norway | 1 | 1 | 0 | 1989-10-10 | |
| Ilene | Vestfold, Norway | 23 | 1 | 0 | 1997-09-18 | |
| Illestadvatnet | Vestfold, Norway | 3 | 2 | 2 | 2011-05-26 | |
| Imetjønn | Agder, Norway | 2 | 2 | 0 | 1989-10-06 | |
| Indre Lafjord | Agder, Norway | 18 | 1 | 0 | 1995-09-27 | |
| Indrehavn | Vestfold, Norway | 2 | 1 | 0 | 1993-11-29 | |
| Inndyr | Nordland, Norway | 7 | 3 | 0 | 2019-04-24 | |
| Innsmøla | Møre og Romsdal, Norway | 2 | 1 | 0 | 1996-09-19 | |
| Jansvik | Nordland, Norway | 1 | 1 | 0 | 1995-10-26 | |
| Jarenvannet | Innlandet, Norway | 7 | 4 | 0 | 1992-09-17 | |
| Jegersborgdammen | Oslo, Norway | 3 | 3 | 0 | 1989-09-06 | |
| Jelkrem | Møre og Romsdal, Norway | 1 | 1 | 1 | 2020-03-23 | |
| Jerkholmen | Agder, Norway | 4 | 1 | 0 | 1996-09-19 | |
| Jomfruland | Telemark, Norway | 1 | 1 | 0 | 1995-09-07 | |
| Jordet skole | Vestfold, Norway | 1 | 1 | 0 | 2003-11-25 | |
| Judaberg | Rogaland, Norway | 9 | 1 | 0 | 1994-12-20 | |
| Justøya | Agder, Norway | 3 | 1 | 0 | 1995-09-08 | |
| Jåbekkvannet | Agder, Norway | 5 | 5 | 0 | 1991-06-11 | |
| Jåstad | Vestland, Norway | 1 | 1 | 0 | 2008-05-14 | |
| Jåsund, Meling, Haga | Rogaland, Norway | 6 | 1 | 0 | 1993-09-28 | |
| Kaldnes | Vestfold, Norway | 1 | 1 | 0 | 2007-03-17 | |
| Kaldvellfjorden | Agder, Norway | 27 | 1 | 0 | 1998-09-24 | |
| Kallevik Sør | Rogaland, Norway | 2 | 2 | 0 | 2017-02-01 | |
| Kalvatræet skole | Vestland, Norway | 1 | 1 | 0 | 2012-03-29 | |
| Karl Johans vern | Vestfold, Norway | 1 | 1 | 0 | 1994-09-23 | |
| Kirkebygden barne- og ungdomsskole | Akershus, Norway | 10 | 7 | 1 | 2022-09-16 | |
| kirkehamn | Agder, Norway | 1 | 1 | 1 | 2015-01-26 | |
| Kirkenær | Innlandet, Norway | 1 | 1 | 0 | 2018-04-28 | |
| Kirkevoll barne- og ungdomsskole | Vestland, Norway | 1 | 1 | 0 | 2020-05-11 | |
| Kise | Innlandet, Norway | 2 | 2 | 0 | 2003-08-22 | |
| Kjeldevatnet | Vestland, Norway | 5 | 4 | 2 | 2024-06-18 | |
| Kjelling | Nordland, Norway | 6 | 4 | 0 | 2014-04-13 | |
| Kjemsjøen | Innlandet, Norway | 5 | 5 | 0 | 1989-09-14 | |
| Kjenestangen | Agder, Norway | 2 | 1 | 0 | 1993-09-24 | |
| Kjøpmannsskjær | Vestfold, Norway | 3 | 1 | 0 | 1993-12-22 | |
| Kjøvangen | Akershus, Norway | 1 | 1 | 0 | 2006-08-23 | |
| Klokkerholmen | Telemark, Norway | 1 | 1 | 0 | 2016-06-07 | |
| Kløfta nord | Akershus, Norway | 3 | 1 | 0 | 2013-04-18 | |
| Knestang | Buskerud, Norway | 1 | 1 | 0 | 2014-04-07 | |
| Knurrvatnet | Nordland, Norway | 2 | 2 | 0 | 1989-08-30 | |
| Kolbeinsrød | Vestfold, Norway | 20 | 1 | 0 | 1997-09-09 | |
| Kolbjørnviksjøen | Østfold, Norway | 18 | 13 | 0 | 1990-08-29 | |
| Kolbotnvannet | Akershus, Norway | 2 | 2 | 0 | 1990-09-25 | |
| Kollevåg | Vestland, Norway | 2 | 1 | 0 | 1993-11-02 | |
| Koltjønna | Trøndelag, Norway | 15 | 8 | 0 | 1992-08-27 | |
| Kolvereid | Trøndelag, Norway | 4 | 1 | 0 | 1995-10-04 | |
| Kongsgårdbukta | Agder, Norway | 6 | 1 | 0 | 1995-10-16 | |
| Kongsheia | Rogaland, Norway | 4 | 4 | 0 | 2019-03-25 | |
| Konnerud | Buskerud, Norway | 1 | 1 | 1 | 2014-05-28 | |
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