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DSS-WISETM LITE CASE 

STUDIES SUMMARY

A State Perspective

A summary of how states are using DSS-WISETM 

Lite as a dam risk management tool

Background

Decision Support System for Water Infrastructure SecurityTM Lite 

(DSS-WISETM Lite) is a web-based, automated two-dimensional 

dam-break flood modeling and mapping capability developed 

by the National Center for Computational Hydroscience 

and Engineering (NCCHE), the University of Mississippi. Its 

development, operation, and maintenance are supported by FEMA.

DSS-WISETM Lite has been used extensively during numerous dam 

incidents and emergencies. FEMA reached out to several states 

asking for case studies of their experience with DSS-WISE and 

received over 100 examples.

4

100%

Four States Responded 

across Four Regions

Four states completed case studies: South 

Carolina (Region IV), New Mexico (Region 

VI), Colorado (Region VIII), and California 

(Region IX).

When Used in an Emergency, 

100% Agreed DSS-WISETM 

Lite had a Positive Impact

All states that used DSS-WISETM Lite in an 

emergency agreed it was effective and had 

a positive impact on emergency response.

We Can Agree

Participants unanimously agreed 

their experience with DSS-WISETM 

Lite would impact how future 

emergency events were handled.

100% of participants also agreed 

that DSS-WISETM Lite was helpful.

We see DSS-WISETM Lite 

as a vital tool for hazard 

classification of dams.

—South Carolina

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Results helped state Dam 

Safety [of ficials] make 

quick decisions in the 

face of questions from 

emergency managers.

—Colorado

Three States Show How 

DSS-WISETM Lite Affected 

Emergency Response

Three of four states provided examples 

where DSS-WISETM Lite affected emergency 

response.

75%

Page 1 of 3

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Speed and ease of use 

allowed users to model 

actual conditions at time 

of failure.

—California

Total States

Emergency 

Response

Positive Impact
2017: Oroville, California

Most noteably, DSS-WISETM Lite was used in the Oroville Dam Incident in 2017. Only an 

inundation map for the main dam was available at the time. In response to the release 

of high flows through a damaged spillway and use of an emergency spillway with hillside 

erosion, over 60 independent model runs were submitted in a 4-day period. DSS-WISETM 

Lite was used to model various failure modes and determine appropriate evacuations.

2018: Snelling, California

In California, an EAP was activated for Moccasin Lower Dam during a flood event due 

to inadequate spillway capacity that resulted in high seepage flows at the downstream 

toe of the dam and potential for dam overtopping. DSS-WISETM Lite confirmed a dam 

failure would flood the fish hatchery downstream, impact a highway road, and be 

absorbed by the downstream reservoir, which led officials to dewater the reservoir 

through a water supply tunnel to alleviate seepage concerns and prevent overtopping. 

2018: South Carolina

In South Carolina, multiple EAPs were activated for several dams during the approach 

of Hurricane Florence. Dam Safety Program staff identified dams that were expected 

to receive the most rainfall and conducted DSS-WISETM Lite simulations to evaluate 

hazard classifications and ascertain accurate mapping would be available for 

distribution to emergency management. 

2019: Soda Springs, California

In California, Lake Van Norden Dam suffered damage to the spillway channel concrete 

liner. The dam owner’s approved innundation map was used during the incident, 

but DSS-WISETM Lite was used to confirm the owner’s inundation area and flood 

parameters. 

Page 2 of 3

Activation of an Emergency Action Plan (EAP)

Four of the case studies identified the use of DSS-WISETM Lite after an EAP was activated. An EAP is a 

formal document that identifies potential emergency conditions at a dam and specifies actions to be 

followed to minimize loss of life and property damage.
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Conclusion

DSS-WISETM Lite is a proven tool that enhances 

dam safety risk management. Diverse stakeholders 

use DSS-WISETM Lite as a tool both to prepare 

ahead of the activation of an EAP and as a 

response tool once an EAP has been activated. 

Overwhelmingly, these case studies show that DSSWISETM Lite has a positive impact, and those who 

use it want to see a continued investment by FEMA 

to run this program.

We are more apt to go to DSS-WISETM for 

initial dam failure consequence estimates 

after this experience.

—Colorado

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“DSS-WISETM has greatly improved risk 

assessment capability for the New Mexico 

Dam Safety Program.

—New Mexico

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“DSS-WISETM Lite allowed for confident 

identification of downstream hazards in the 

event of a dam failure.

—South Carolina

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“Given the efficiency and versality of DSSWISETM, it allows users to model real-time 

conditions. 

—California

About the Dams Studied

The dams from these case studies were diverse. The dams were made from different materials and 

methods, owned by different entities, and had various Population at Risk (PAR) statistics.

For each DSS-WISETM study, PAR 

ranged between 0 to >200,000, 

with an average PAR of 6,000.

A large majority of the dams 

listed in the case studies were 

earthen dams.

15 85%

The dams from the case studies 

were owned by 15 different 

stakeholder groups.

DSSWISETM HCOM

DSS-WISETM Human Consequence Module (HCOM) 

is an analytical module for automated assessment 

of the human consequences of dam-break floods. 

It’s accessible 24/7 to registered users from FEMA, 

federal agencies, and state dam safety offices. DSSWISETM HCOM uses the results of flood simulation 

using DSS-WISETM Lite to provide maps of:

• Flood hazard risk for people caught outdoors 

and indoors.

• Potentially lethal flood zones (PLFZ) for 

children and adults