The Planning Board may require such engineering and other documentary evidence as it deems necessary in order to determine the suitability of such area for such use, including, but not limited to, topographic data, proposed location and elevation of structures and facilities and any other information that demonstrates that the use itself would remain safe from floodwaters that safe access can be provided to the area in case of flood; that its water and sewage disposal methods would remain safe and sanitary; that surface drainage flows would be adequately provided for; and that any proposed grade or structural changes within the floodplain or the floodway would not alter stream dynamics in a way which is detrimental to the health, safety and welfare of residents and land uses both upstream and downstream of such grade or structural alteration. The Planning Board shall consult with other individuals and agencies as necessary, including, but not limited to, the Town Engineer, the Federal Emergency Management Agency (FEMA), the Department of Environmental Conservation and the United States Soil Conservation Service. Notwithstanding the foregoing, the Planning Board may waive the requirements of this section upon finding that any other agency, such as the Department of Environmental Conservation, will duplicate this required review pursuant to its grant of any requested permit.[1]