Reclamation District No. 1001 (RD 1001) provides flood protection for approximately 43,395 acres and a population of 1,540, including the communities of East Nicolaus, Nicolaus, Pleasant Grove, Rio Oso, Trowbridge and Verona.  RD 1001 receives assessments from 761 parcels in Sutter County and 26 parcels in Placer County.

RD 1001 is responsible for the operations and maintenance of 44 miles of project levees, 16 miles of non-project levees, over 100 miles of drainage ditches and canals, a main drain pumping plant located at the Natomas Cross Canal and three smaller drainage pumping facilities on Yankee Slough. RD 1001's levee system protects State Highways 65, 70, and 99, two active Union Pacific Railroad lines, two volunteer fire departments, a Pacific Gas and Electric substation and numerous transmission lines, both the Rio Oso and Nicolaus Post Offices, two elementary schools, and the Nicolaus Cemetery.