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Black Wash Floodplain Study


Study status:  LOMR approved, effective October 12, 2012 


For more information, please contact the Project Manager:
Lynn Orchard, Chief Hydrologist
(520) 724-4600

The Pima County Regional Flood Control District has submitted proposed changes to the Black Wash Floodplains to the Federal Emergency Management Agency (FEMA). The proposed revisions start ½ mile south of Valencia Road and extend upstream to approximately 2 miles upstream to W. Tetakusim Road. The proposed map revisions reflect better topographic information, and revised hydrologic and hydraulic modeling. The maps cover portions of Sections 11, 12, 13, and 24 of Township 15 South, Range 12 East; and Sections 18 and 19, Township 15 South, Range 13 East in eastern Pima County, Arizona. If accepted by FEMA, the revised Floodplains, Floodways, and Base Flood Elevations would modify portions of Flood Insurance Rate Maps 04019C2265L, 04019C2270L, 04019C2855L and 04019C2860L. Please read the FEMA approval letter for case number 12-09-1311P for more information.

Frequently Asked Questions (FAQs)

The most frequently asked questions regarding the re-mapping of the floodplain for the Black Wash, the Flood Insurance Rate Maps, Letters of Map Revision, Flood Insurance and more can be found in an LOMR FAQ. The District also has a Flood Insurance page that answers many common questions about flood insurance.


Below is a map of the project area. The map is clickable, so click within a map area or on the map label to get a PDF map showing greater detail. Each map shows the current and proposed FEMA floodplain for portions of the project area.
Clickable map of the project area to access detailed floodplain maps. Click to view Black Wash LOMR detail map 1 Click to view Black Wash LOMR detail map 2. Click to view Black Wash LOMR detail map 3. Click to view Black Wash LOMR detail map 4. Click to view Black Wash LOMR detail map 5.

If you have trouble accessing the maps through the index map above, they are available below.