The board is scheduled Nov. 4, 2026, to consider adopting a 68‑square‑mile San Tan Valley Area Drainage Master Plan prepared by Entellus, Inc.; the staff report recommends approval and says the plan identifies 15 areas of interest with channel, culvert and basin recommendations and a regional concept coordinated with Arizona State Land Department.

The presenter explained how tide gates, pump stations and managed lake levels at Windsor Woods, Lake Windsor, Lake Trashmore and London Bridge Creeks will be used to isolate neighborhoods from tidal surge and create storage to receive runoff.

A Horsley Witten draft report presented to the Select Board found elevated nitrogen and phosphorus in Long Pond and recommended accelerating sewer work, pursuing stormwater best management practices and considering in‑lake treatments such as alum or dredging; dam management was suggested as a lower‑cost test to reduce residence time.

Experts discuss sizing and capacity of rain gardens for stormwater management.

The Seymour Plan Commission voted 8-0 to recommend rezoning a parcel at US 31 and US 50 from RS to I2 for a prospective Becknell Industrial development. Neighbors urged protections on traffic access, stormwater, lighting and water service; the developer agreed to two commitments.