Such board is authorized to enter upon and to take and hold, by purchase, condemnation or otherwise, any real property or interest therein which it determines is necessary for use in connection with the flood prevention, climate resilience and erosion control system. Whenever the board is unable to agree with the owner of any such property as to the compensation to be paid for the taking thereof, the board, in the name of the municipality, may bring condemnation proceedings in accordance with the procedure provided by part I of chapter 835 for condemnation by municipal corporations generally. In such case, the court or judge may permit immediate possession of such property by the board in accordance with the procedure provided by said chapter.