Existing needs to manage flood risk in the U.S. are underserved by available flood hazard information. This contributes to an alarming escalation of flood impacts that amount to hundreds of billions of dollars per year and countless disrupted lives and affected communities. Making information about flood hazards useful for the range of decisions by actors that dictate the consequences of flooding poses many challenges.

This dataset contains a collection of flood hazard mapping layers for two sites in Southern California: Newport Bay and the Tijuana River Estuary. The flood hazard data layers were created using a Collaborative Flood Modeling (CFM) approach, whereby researchers and end-users at the two coastal sites co-developed fine-resolution flood hazard models and maps responsive to decision-making needs.

Newport Beach: Historical Event Flood Depth (2005)

This map layer contains the resulting flood depth (US feet) from the extreme high tide event that occurred on January 10th 2005. 

NB_Historical_Flood_2005.tif

 

Newport Beach: 1% Annual Chance Flood Depth (2015, 2035, 2050)

These map layers contain maximum flood depths (US feet) produced by 1% AEP events occurring under 2015 sea level conditions. Flood drivers considered are tide, streamflow, wave overtopping, and rainfall. The displayed flood depths are not the result of one event, but the combination of flood depths produced by each flood driver as occurring independently and modeled separately.

NB_1pct_Chance_Flood_Depth_2015.tif
NB_1pct_Chance_Flood_Depth_2035.tif
NB_1pct_Chance_Flood_Depth_2050.tif

 

Newport Beach: Chance of Flooding (2015, 2035, 2015)

These map layers contain annual chance of flooding over ankle depth under 2015, 2035, and 2050 sea level conditions, and the chance of flooding over 10 years from 2015, 2035, and 2050. Flood causes considered are tide, streamflow, wave overtopping, and rainfall. The displayed probabilities of flooding are not the result of one event, but the combination of probabilities from events from different flood causes, with different chance, occurring independently, and modeled separately.

NB_Chance_of_Flooding_2015.tif
NB_Chance_of_Flooding_2035.tif
NB_Chance_of_Flooding_2050.tif

 

Newport Beach: Chance of Road Blockage (2015, 2035, 2015)

These map layers contain probability of road blockage to sedans under 2015. 2035, and 2050 sea level conditions. A 1 ft fording depth is used as a cutoff to mark flooding unsafe for sedans. Flood drivers considered are tide, streamflow, wave overtopping, and rainfall. The probabilities of flooding are not the result of one event, but the combination of probabilities from events from different flood drivers, with different exceedance probabilities, occurring independently, and modeled separately.

NB_Chance_Road_Blockage_2015.tif
NB_Chance_Road_Blockage_2035.tif
NB_Chance_Road_Blockage_2050.tif

 

Newport Beach: "King Tide with Rainfall” Flood Depth (1/2”, 1”)

These map layers contain the resulting flood depth from two rainfall events (approximatley 0.5" and 1") coinciding with a King Tide during 2015 climate and sea level conditions. The probability of a 0.5" rainfall event to coincide with the King Tide is on average once every 278 years, or 0.36% annually, while the probability of a 1" rainfall event to coincide with the King Tide is on average once every 1391 years, or 0.072% annually.

NB_King_Tide_with_0p5in_Rainfall_Flood_Depth.tif
NB_King_Tide_with_1in_Rainfall_Flood_Depth.tif

 

Newport Beach: Hours of Inundation Per Day (2015, 2035, 2015)

These map layers contain duration of flooding in hours for current conditions (2010, 2015) and future conditions (2035, 2050) for two scenarios: 1) in the event of a 1% annual chance tide, and 2) under average daily duration of inundation in the Newport Upper Bay based on 2010 sea level observations and projected 2035 and 2050 sea level rise conditions.

NB_1pct_Tide_Flood_Duration_2015.tif
NB_1pct_Tide_Flood_Duration_2035.tif
NB_1pct_Tide_Flood_Duration_2050.tif
NB_2010_Upper_Bay_Average_Inundation_Duration.tif
NB_2035_Upper_Bay_Average_Inundation_Duration.tif
NB_2050_Upper_Bay_Average_Inundation_Duration.tif

 

Newport Beach: Causes of Flooding (2015/2035/2050)

These map layers contain the primary cause of flooding producing the deepest flood depth locally in the case of a 1% annual chance event occurring under 2015, 2035, and 20150 sea level conditions. The displayed flood extent is not the result of one event, but the combination of flood extents produced by each flood cause as occurring independently and modeled separately.

NB_Causes_of_Flooding_2015.tif
NB_Causes_of_Flooding_2035.tif
NB_Causes_of_Flooding_2050.tif

 

Newport Beach: 1% Annual Chance Flood Depth with Proposed Flood Wall and Flood Wall Failure

These map layers contain the resulting flood depth (US feet) from a 9.1 ft NAVD88 tide after seawalls surrounding the Balboa Isles have been capped to 9.5 ft NAVD88. Based on the California Coastal Commission intermediate sea level rise projections of 2015 (IPCC scenario A1B), a 9.1 ft NAVD88 tide has a 1% chance of occurrence in the year 2050. In other words, it represents the 100 year return period tide for the year 2050. We also show the flooding resulting from a localized failure of the capped wall on Balboa Island during a 7.5 ft tide.

NB_1pct_Flood_Raised_Seawall.tif
NB_7p5_Tide_Raised_Seawall_Failure.tif

 

Tijuana River Valley: Flood Depth (1983, 1% AEP, 20% AEP)

These map layers contain maximum flood depths (meters) produced by three scenarios: 1) a historical 1983 flood, 2) a 1% AEP event occurring under 2015 sea level conditions, and 3) a 20% AEP event occurring under 2015 sea level conditions. Flood drivers considered are streamflow from the Tijuana River and it's canyon tributaries in the Tijuana River Estuary (Smuggler's Gulch and Goat Canyon), as well as stormtide conditions.The displayed flood depths are not the result of one event, but the combination of flood depths produced by each flood driver as occurring independently and modeled separately.

TRV_1983_Flood_Depth.tif
TRV_1pct_Chance_Flood_Depth_2015.tif
TRV_20pct_Chance_Flood_Depth_2015.tif

 

Tijuana River Valley: Flood Force (1983, 1% AEP, 20% AEP)

These map layers contain maximum flood force (m²/s) produced by three scenarios: 1) a historical 1983 flood, 2) a 1% AEP event occurring under 2015 sea level conditions, and 3) a 20% AEP event occurring under 2015 sea level conditions. Flood drivers considered are streamflow from the Tijuana River and it's canyon tributaries in the Tijuana River Estuary (Smuggler's Gulch and Goat Canyon), as well as stormtide conditions.The displayed flood forces are not the result of one event, but the combination of flood depths produced by each flood driver as occurring independently and modeled separately.

TRV_1983_Flood_Force.tif
TRV_1pct_Chance_Flood_Force_2015.tif
TRV_20pct_Chance_Flood_Force_2015.tif

 

Tijuana River Valley: Flood Shear Stress (1983, 1% AEP, 20% AEP)

These map layers contain maximum flood shear stress (kg/m²) produced by three scenarios: 1) a historical 1983 flood, 2) a 1% AEP event occurring under 2015 sea level conditions, and 3) a 20% AEP event occurring under 2015 sea level conditions. Flood drivers considered are streamflow from the Tijuana River and it's canyon tributaries in the Tijuana River Estuary (Smuggler's Gulch and Goat Canyon), as well as stormtide conditions.The displayed flood shear stresses are not the result of one event, but the combination of flood depths produced by each flood driver as occurring independently and modeled separately.

TRV_1983_Flood_Shear_Stress.tif
TRV_1pct_Chance_Flood_Shear_Stress_2015.tif
TRV_20pct_Chance_Flood_Shear_Stress_2015.tif

 

Tijuana River Valley: Chance of flooding

This map layer contain annual chance of flooding over ankle depth under 2015 sea level conditions. Flood causes considered are storm tides, canyon flows, and Tijuana River flows with a range of return periods, from 1 to 100 years. The displayed probabilities of flooding are not the result of one event, but the combination of probabilities from events from different flood causes, with different chance, occurring independently, and modeled separately.

TRV_Chance_of_Flooding.tif

 

Tijuana River Valley: Flood Management Strategies

These map layers represent two management strategies to deal with flooding in the Tijuana River Valley. The first strategy looks at the impact of channel dredging on a 20% AEP flood event. The second one looks at the impact of removing historically placed fill material downstream of Hollister Bridge (locally known as Borwn Fill) on a hindcast of the 1983 flood event.

TRV_Channel_Dredging.tif
TRV_Fill_Removal.tif

 

Tijuana River Valley: Implications of Flooding on Health

This map layer contains depth and locations of water that did not freely drain to the Pacific Ocean by overland flow following the 1% AEP Tijuana River flood. The residual flood depth serves as a surrogate for standing water which could represent a public health risk since standing water increases mosquito activity.

TRV_Channel_Dredging.tif
TRV_Fill_Removal.tif