Neutrinos do not travel faster than light in any medium, including water. According to our current understanding of physics, the theory of relativity states that nothing with mass can exceed or reach the speed of light in a vacuum.
Neutrinos are subatomic particles that have a tiny amount of mass. They are electrically neutral and interact very weakly with matter, which allows them to pass through ordinary matter, including water, with minimal interaction. Because of their weak interaction, neutrinos can travel long distances through dense materials like water without significant absorption or scattering.
However, neutrinos still travel at speeds that are very close to the speed of light in a vacuum. In water, their speed is slightly slower than the speed of light due to the effects of the medium. When a particle like a neutrino moves through a material, it can interact with the atoms and molecules of the medium, causing some delay or reduction in its speed compared to its speed in a vacuum.
It's worth noting that there have been experimental claims in the past suggesting that certain particles, including neutrinos, may have traveled faster than light. However, these claims were later found to be due to measurement errors or other factors. The current scientific consensus is that the speed of light is an ultimate speed limit, and neutrinos, like all other particles with mass, obey this limit.