US Army Corps of Engineers
Los Angeles District Website

TNWs & Navigable Waters in Los Angeles District

The waterways and waterbodies listed below are regulated within Los Angeles District as "Traditional Navigable Waters" (TNWs), pursuant to Section 404 of the Clean Water Act, and/or "Navigable Waters," pursuant to Section 10 of the Rivers and Harbors Act.  These jurisdictional waters have been identified as a result of studies conducted by the Corps, or federal court rulings, and do not represent all waters potentially considered to be Section 404 TNWs or Section 10 Navigable Waters.  In particular, all waters subject to the ebb and flow of the tide may be considered Section 10 Navigable Waters and Section 404 Traditional Navigable Waters, beyond those specifically identified below.

CALIFORNIA

Waterway / Waterbody Navigation Study Determination1 (per Section 10 Rivers and Harbors Act; 33 CFR Section 329.14) Traditional Navigable Water Determination2 (per Section 404 Clean Water Act; 33 CFR Section 328.3(a)(1))
Imperial County
Alamo River Nonnavigable (D11 MEMO 25 JAN 74) Not evaluated
New River Nonnavigable (D11 MEMO 18 MAR 77) Not evaluated
Salton Sea Nonnavigable (COMDT LTR 3 JAN 61) Navigable (SPL MFR 24 JAN 2001)
Sunbeam Lake Not evaluated Navigable (SPL MFR 19 FEB 2008)
Inyo County
Owens Lake Navigable (SPL AJD APR 2010) Navigable (SPL AJD APR 2010)
Kern County
Tejon Lake Not evaluated Navigable (SPL MFR 03 SEP 2008)
Los Angeles County
Alamitos Bay (to MHW) Navigable (D11 MEMO 25 JAN 74) Navigable
Ballona Creek (to 2.6 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Domingez Channel (to Vermont Ave) Navigable (D11(dl) MEMO 21 JUL 81) Navigable
Irwindale Quarry Nonnavigable (Dll MEMO 17 JAN 80) Not evaluated
Los Angeles/Long Beach Harbor (to MHW; to mile 8) Navigable (Dll MEMO 23 AUG 78; CoE LTR 17 FEB 58) Navigable
Los Angeles River
- to PCH Bridge/MHW
- to 2.5 ft MSL
- Confluence of Arroyo Calabasas and Bell Creek to San Pedro Bay
Navigable (Dll MEMO 23 AUG 78)
Navigable (CoE LTR 29 NOV 72)
Not evaluated
Navigable
Navigable
Navigable (EPA JD 06 JUL 2010)
Malibu Lake Not evaluated Navigable (SPL MFR 13 JUN 2008)
Playa Del Ray Harbor (to 2.5 ft MSL) Navigable (N/A) Navigable
Puddingstone Reservoir Not evaluated Navigable (SPL MFR 25 MAR 2008)
Redondo Beach Navigable (CoE LTR 17 FEB 58) Navigable
Orange County
Anaheim Bay (Entire Bay; to 2.5 ft MSL) Navigable (D11 MEMO 27 MAY 80; CoE LTR 29 NOV 72) Navigable
Bolsa Bay (to MHW; to 2.5 ft MSL) Navigable (Dll MEMO 22 JAN 80; CoE LTR 29 NOV 72) Navigable
Greenville-Banning Channel (to 19th St. Bridge) Navigable (D11 MEMO 9 FEB 78) Navigable
Lower San Diego Creek Navigable (SPL AJD 31 OCT 2016) Navigable (SPL AJD 31 OCT 2016)
Newport Bay (Upper) (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
San Gabriel River (to 7th Street Bridge; to 2.5 ft MSL) Navigable (Dll MEMO 16 SEP 80; CoE LTR 29 NOV 72) Navigable
San Juan Creek (to 2.6 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Santa Ana River (to 19th Street Bridge) Navigable (D11 MEMO 9 FEB 78) Navigable
Talbert Flood Control Channel (to MWH) Navigable (D11(dl) MEMO OF 26 JUL 84) Navigable
Westminster Flood Control Channels: Bolsa Chica Channel (C02), Westminster Channel (C04), East Garden Grove-Wintersburg Channel (C05) Navigable (SPL AJD 22 APR 2019) Navigable (SPL AJD 22 APR 2019)
Riverside County
Lake Elsinore Not evaluated Navigable (SPL MFR 20 MAR 2008)
Lake Perris Not evaluated Navigable (SPL MFR 08 NOV 2007)
Salton Sea Nonnavigable (COMDT LTR 3 JAN 61) Navigable (SPL MFR 24 JAN 2001)
San Bernardino County
Big Bear Lake Not evaluated Navigable (SPL MFR 16 NOV 2007)
San Diego County
Agua Hediona Lagoon (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72; D11 MEMO 29 MAR 80) Navigable
Batiquitos Lagoon (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Buena Vista Lagoon (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Camp Pendleton Harbor Navigable (CoE LTR 17 FEB 58) Navigable
La Plaeta Creek (to SD & AE Crossing) Navigable (D11 MEMO 16 JUN 80) Navigable
Las Chollas Creek (to mile 0.35) Navigable (D11 MEMO 17 JUL 78) Navigable
Los Penasquitos Lagoon (to I-5 Bridge; to 2.5 ft MSL) Navigable (Dll MEMO 5 MAR 86CoE LTR 29 NOV 72) Navigable
Mission Bay (Upper) (to 2.6 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Otay River (to MHW) Navigable (D11 MEMO 22 MAR 77) Navigable
San Diego River (to MHW; to 2.7 ft MSL) Navigable (D11 MEMO 30 SEP 76; CoE LTR 29 NOV 72) Navigable
San Diego Bay (lower) (to 3 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
San Dieguito River (to I-5; to 2.5 ft MSL) Navigable (Dll MEMO 8 MAR 85; CoE LTR 29 NOV 72) Navigable
San Elijo Lagoon (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
San Luis Rey River (to Route 76; to 2.5 ft MSL)  Navigable (D11 MEMO 12 FEB 79; CoE LTR 29 NOV 72) Navigable
San Mateo Creek (to 2.6 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Santa Margarita River (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Sweetwater River (to mile 0.8) Navigable (COMDT LTR 23 JAN 76) Navigable
Tecolate River (to MHW) Navigable (Dll MEMO 27 JAN 78) Navigable
Tijuana Estuary (to 2.5 ft. MSL) Navigable (CoE LTR 29 NOV 72) Navigable
San Luis Obispo County
Butano Creek (to mile 1.7; to mile 1.4) Navigable (D12 LTR 6 FEB 79; CoE LTR 2 AUG 71) Navigable
Chorro Creek (to mile 1.2; to mile 11) Navigable (D12 LTR 6 FEB 79; CoE NOTE 15 JUL 78) Navigable
Morro Bay (Lower) (to MHW; to 2.4 ft MSL) Navigable (D12 LTR 6 FEB 79; CoE LTR 29 NOV 72) Navigable
Pismo & Arroyo Grande Creeks (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Port San Luis (tidal) Navigable (N/A) Navigable
San Luis Obispo Creek (to mile 1.3; to 2.5 ft MSL) Navigable (D12 LTR 6 FEB 79; CoE LTR 29 NOV 72) Navigable
San Simeon Bay (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
San Simeon Creek (to mile 0.5) Navigable (D12 LTR 6 FEB 79) Navigable
Twitchell Reservoir Not evaluated Navigable
Santa Barbara County
Arroyo Hondo (to SR 101) Navigable (D11 LTR 7 SEP 79) Navigable
Carpinteria (El Estero) Marsh (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Devareaux Ranch Lagoon (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Franklin Creek Nonnavigable (D11 LTR 5 JAN 76) Not evaluated
Goleta Slough (to MHW; to 2.5 ft MSL Navigable (COMDT LTR 12 Nov 69; CoE LTR 29 NOV 72) Navigable
San Antonio Creek Nonnavigable (D11 MEMO 26 SEP 79) Not evaluated
San Pedro Creek Nonnavigable (D12 MEMO 4 FEB 79) Not evaluated
Santa Barbara Harbor Navigable (N/A) Navigable
Santa Maria River (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Santa Ynez River (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Tecolotilo Creek (to Fowler St. Bridge) Navigable (COMDT LTR 12 NOV 69) Navigable
Twitchell Reservoir Not evaluated Navigable
Ventura County
Calleguas Creek (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Mugu Lagoon (to 2.5 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable
Port Hueneme Navigable (N/A) Navigable
Santa Clara River Nonnavigable (D11 MEMO 3 JUN 87; D11 MEMO 29 NOV 72) Not evaluated
Ventura River (to 2.6 ft MSL) Navigable (CoE LTR 29 NOV 72) Navigable

Tidal datums used above to identify extent of Corps jurisdiction include Mean High Water (MHW) and Mean Sea Level (MSL).

ARIZONA

Waterway / Waterbody Navigation Study Determination1 (per Section 10 Rivers and Harbors Act; 33 CFR Section 329.14) Traditional Navigable Water Determination2 (per Section 404 Clean Water Act; 33 CFR Section 328.3(a)(1))
Colorado River
- Mexican Border to Hoover Dam Navigable (ARIZONA V. CALIF., 283 U.S. 423 (1931) & ARIZONA V. CALIF., 298 U.S. 558 (1936)) Not evaluated
- Hoover Dam to Grand Wash Navigable (CoE LTR 2 JAN 75) Not evaluated
- Grand Wash to Glen Canyon Dam Navigable (CoE LTR 8 NOV 73) Not evaluated
- Glen Canyon Dam to Cataract Canyon (Mile 176) Navigable (U.S. V. UTAH, 283 U.S. 64 (1931)) Not evaluated
- Lake Powell Navigable (N/A) Navigable
Gila River
- Coolidge Dam to Winkleman Not evaluated Yes (SPL MFR 12 MAR 2008)
- Powers Butte to Gillespie Dam Not evaluated Yes (SPD Memorandum 17 OCT 2008; SPD MFR 17 OCT 2008)
Santa Cruz River
- Tubac gage station (USGS #09481740) to the Continental gage station (USGS #09482000) Not evaluated Yes (SPL MFR 23 MAY 2008)
- Roger Road wastewater treatment plant (WWTP) to the Pima/Pinal County line Not evaluated Yes (SPL MFR 23 MAY 2008)

 

1Section 10 - NAVIGABLE WATERS OF THE UNITED STATES
Navigable waters of the United States are those waters that are subject to the ebb and flow of the tide and/ or are presently used, or have been used in the past, or may be susceptible for use to transport interstate or foreign commerce. A determination of navigability, once made, applies laterally over the entire surface of the waterbody, and is not extinguished by later actions or events which impede or destroy navigable capacity. All waters determined to be navigable waters of the U.S. are also considered to be Traditional Navigable Waters regulated under Section 404 of the Clean Water Act. This excludes Section 10 aquatic resources that are now "fast land"/dry land that are not considered jurisdictional under Section 404.

2Section 404 - TRADITIONAL NAVIGABLE WATERS:
Traditional navigable waters (or waters that are traditionally understood as navigable) refers to all waters which are currently used, were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters subject to the ebb and flow of the tide.
Territorial seas are defined in CWA section 502(8), 33 U.S.C. 1362(8), as "the belt of the seas measured from the line of ordinary low water along that portion of the coast which is in direct contact with the open sea and the line marking the seaward limit of inland waters, and extending seaward a distance of three miles." The territorial seas establish the seaward limit of "waters of the United States".
Tidal waters and waters subject to the ebb and flow of the tide: The terms tidal waters and waters subject to the ebb and flow of the tide mean those waters that rise and fall in a predictable and measurable rhythm or cycle due to the gravitational pulls of the moon and sun. Tidal waters and waters subject to the ebb and flow of the tide end where the rise and fall of the water surface can no longer be practically measured in a predictable rhythm due to masking by hydrologic, wind, or other effects.