The government must ensure temporary shelters are available, and have adequate supplies, before asking residents to move, Interfaith Network says.
Flash floods in the March–May long rain season have left at least 229 dead, thousands displaced and living in camps, and massive property damage.
Forecasted rains are expected to worsen the situation, with more than 1.2 million individuals at risk of cholera.
He emphasized the importance of conducting public participation before the implementation of any project.