If your neighbor has obtained an approved Floodplain Use Permit and/or Building Permit, it should minimize adverse impacts downstream.
If the development or changes are not permitted, you can report them to the Maricopa County Planning and Development Department Code Enforcement Division. If you suspect the development is within a delineated floodplain within Maricopa County you can contact the District to open an investigation, 602-506-2419. All other potential floodplain violations, not within unincorporated Maricopa County, will be directed to the applicable jurisdiction. Return to Flood Control District