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H A Z A R D M I T I G A T I O N

A T W O R K :

T W O A L A B A M A C O M M U N I T I E S

Federal Emergency Management Agency

F E M A

E X E C U T I V E S U M M A RY ............................................................ 1

H A Z A R D M I T I G AT I O N ........................................................... 2

B E N E F I T- C O S T A N A LY S I S .................................................... 4

T H E 1 9 9 0 A N D 1 9 9 4 F L O O D S ......................................... 6

B E N E F I T- C O S T A N A LY S I S : E L B A ................................. 8

B E N E F I T- C O S T A N A LY S I S : G E N E VA ......................1 0

T H E M A R C H ’ 9 8 F L O O D S ................................................1 2

C O N C L U S I O N...............................................................................1 4

T A B L E O F C O N T E N T S

1Hazard Mitigation at Work: Two Alabama Communities

E X E C U T I V E S U M M A R Y

Each year natural disasters causemillions of dollars in damages. Butthe toll doesn’t end there. The

human misery that inevitably follows inthe wake of disasters can’t be measured indollars. As footage of disasters is broad-cast to the homes of millions, a questionon people’s minds is: can’t something bedone about this?

The answer is yes. Something isbeing done. It’s called hazard mitigation,and FEMA is leading the way to helpcommunities use hazard mitigation tomake themselves disaster-resistant. Thisreport tells the story of how FEMAhelped two Alabama communities reducethe impact of repeated flooding.

We begin with a discussion of FEMA’sHazard Mitigation Grant Program(HMGP). This program, which is a partof the Robert T. Stafford Disaster Reliefand Emergency Assistance Act (“TheStafford Act”), assists states and localcommunities in implementing hazardmitigation measures after major disasters.

The next section provides an overviewof benefit-cost analysis, FEMA’s mecha-nism for evaluating mitigation projects.Benefit-cost analysis, which is requiredby the Stafford Act, determines whetherhazard mitigation projects will be cost-effective. In this context, cost-effectivemeans: the cost of funding the project isless than the cost of damages in futuredisasters without the measure.

We then explore how the cities of Elbaand Geneva, Alabama endured floodingover the past several years. Both have ahistory of flooding, and both were severelydamaged in the floods of 1990 and 1994.

This section reviews the FEMA-fundedhazard mitigation projects implementedin each community after the floods: theinstallation of a stormwater drainagesystem in Elba, and the removal ofof flood-prone properties in Geneva.

Next, we explain how the benefit-costanalyses were conducted for each projectand what they showed. As it turned out,the projects prevented flood damages ineach community only a few years afterthey were implemented.

In March 1998, heavy rainstorms causedmore flooding in southeast Alabama. Whilethe 1998 flooding was generally not assevere as in 1994, both Elba and Genevaagain suffered extensive damage. But thanksto the mitigation projects put in place af-ter the 1994 floods, over a million dollarsin damages were avoided. Theresults underscore the need for hazard-prone communities to get serious aboutmitigation.

The following pages tell the story oftwo communities that—with help fromFEMA and the state of Alabama—havealready realized substantial savings indisaster-related damages.

Elba and Geneva, Alabama.

“. . .Damages [from the March

1998 flood] were significantly

reduced by the recovery and

mitigation measures that were

implemented after the 1994

floods.”

— The President’s Long-Term

Recovery Action Plan

Alabama, March 1998

For an in-depth review of the analyses presented here,see Appendix to this report.

Hazard Mitigation at Work: Two Alabama Communities2

H A Z A R D M I T I G A T I O N

The benefits that accrue from a

hazard mitigation measure are the

avoided damages. The damages

avoided are defined as the differ-

ence between expected future

damages with and without. . .the

hazard mitigation measure.

Disasters are inevitable events thatwe can’t predict or control.But how we reduce, or mitigate,

their effects is something that we cancontrol. And that’s where FEMA’s Haz-ard Mitigation Grant Program (HMGP)comes in.

WHAT IS HAZARD MITIGATION?

In lay terms, hazard mitigation is simplyan investment made today that will re-duce the toll from disasters tomorrow.

President Clinton and FEMA DirectorJames L. Witt have made it a priority toend the cycle of rebuilding from disasters,where states and communities are con-stantly forced to pick up the pieces. That’swhy FEMA funds hazard mitigationprojects through the HMGP.

The program is targeted at communitiesthat are especially prone to natural disas-ters. Local governments work with the stateto identify the best mitigation project fortheir area. Typical flood projects includeremoving or elevating repetitively floodedstructures, or retrofitting public facilities andimproving stormwater drainage.

Elba and Geneva, Alabama are

good examples of what commu-

nities can do about repetitive

flooding. They were selected

for this report because:

• each has a history of flood-

ing, most recently in 1998

and 1994

• each received funding from

FEMA for mitigation projects

that were identified after

the 1994 floods and com-

pleted before the March

1998 floods

• the measures were put to the

test in a real disaster not

long after the measures were

carried out

Community Selection. . . at a Glance

Detail from FEMA’s Region IV Hazard Mitigation Grant Application.

HAZARD M ITIGATION GRANTS

In 1988, the HMGP was incorporated intothe Stafford Act, the law that governsFEMA’s disaster recovery activities. Fed-eral funding under the HMGP is based on15% of disaster relief funds spent on Pub-lic and Individual Assistance programs foreach disaster.

Project applications are then submittedto FEMA for review, where they mustmeet several eligibility criteria before theycan be approved. Depending on theproject type, eligibility review can include:environmental compliance, floodplainmanagement regulations, benefit-costanalysis, executive orders, and engineer-ing feasibility.

— Hazard Mitigation Grant Program

Interim Guidance


HAZARD M I T IGAT ION

In 1988, the Hazard Mitigation

Grant Program was incorporated

into the Stafford Act, the law that

governs FEMA’s disaster recovery

activities.

FLOOD M IT IGATION PROJECTS

There is a wide variety of flood mitigationprojects. And while many projects, suchas elevating buildings and upgradingstormwater drainage systems, may becost-effective solutions in small- tomedium-sized floods, they don’t eliminatethe flood threat completely. In the largestfloods, even the best preventive mitiga-tion measures may fail.

The only 100% effective mitigation projectis known as an acquisition project. Anacquisition project (or “buyout”) is afederally funded measure to purchase andremove buildings from the floodplain. As aresult, the risk of future flooding to thebuilding is zero. The town of Geneva ap-plied and received funding to acquirehomes and businesses in the low-lying areaknown as “Baptist Bottoms.”

But acquisitions may not be the best miti-gation approach for structures with lowto moderate flood risk. Elba is a case inpoint. Instead of demolishing structuresin the floodplain, the town applied forand was granted funds to install a pumpsystem to reduce frequent stormwaterflooding within the town’s ring levee.

A NOTE ABOUT BENEFIT-COST

ANALYSIS

Before 1993, there were no consistent stan-dards for evaluating hazard mitigationprojects. By setting a reliable bench-mark—cost-effectiveness—we can nowdetermine whether a project is worth in-vesting in now for the benefits of avoidingdisaster-related damages in the future.

SOFTWARE THAT ANALYZES

MITIGATION BENEFITS & COSTS

To standardize the analysis and make iteasier to complete, FEMA has developedsoftware to analyze mitigation projectsfor several different hazards. For Elba andGeneva, FEMA used the benefit-costanalysis application for riverine flooding.The benefits of avoided damages andlosses are broken down into the followingcategories:

• building/infrastructure

• building contents

• displacement costs

• loss of rental income

• loss of business income

• emergency services

Analysts use the software to compare thelong-term benefits of a project to its cost.

The next section examines in detail howbenefit-cost analysis actually works.

• Estimates future benefits

over life of project

• Benefits are damages that

would result without the

measure—and are avoided

with it

• Helps communities choose

best project

Benefit-Cost Analysis. . . at a Glance


B E N E F I T- C O S T A N A LY S I S

“Any time there was a flood, the

residents in Baptist Bottoms were

the hardest hit because they lived

in the lowest area of our town.

Most of them participated in the

buyout program after the ’94

floods and have now been

relocated. . .out of the flooding

area.”

Nobody can predict exactly whenthe next disaster will happen—next week, next year, or next

century. But through a combination offlood hazard data, engineering expertise,and historical flood observations, we canaccurately estimate the probability andseverity of future floods.

WHY BENEFIT-COST ANALYSIS?

Office of Management and Budget (OMB)regulations require all hazard mitigationprojects to be cost-effective before theycan be approved for funding. What doesthis mean? In the language of hazard miti-gation, it means benefit-cost analysis mustbe used to determine whether a project’sbenefits—avoided damages in future di-sasters—outweigh its up-front costs. Putsimply, if a benefit-cost analysis concludesthat a project that costs $1 million todaywill save $2 million in potential flooddamages over the life of the project, thenit’s cost-effective.

NUTS & BOLTS

The end result of a benefit-cost analysisis called a benefit-cost ratio. The benefit-cost ratio is determined by dividing esti-mated project benefits by total projectcosts. In the above example, the ratiowould be 2.0.

Benefit-cost analysis is based on calcula-tions of hazard (the frequency and sever-ity of a disaster), avoided future damages,and risk (the threat of damage to buildingsand infrastructure). Similar concepts areused for all disasters—from hurricanes andfloods to earthquakes.

F LOOD H A ZA RD DATA

For flood mitigation projects, FEMA’ssoftware uses flood hazard data to createa picture of the probability and severityof flooding at the project site. Flood haz-ard data can be taken from FEMA’s FloodInsurance Studies, USGS surveys, and/orhistorical observations.

Flood hazard data include flood frequen-cies (10-year, 50-year, 100-year, etc.), dis-charges (amount of river or stream waterflow), and flood levels. The software com-bines flood frequency and elevations tocalculate likely flooding in one-foot incre-ments above a building’s first floor.

The frequency (probability) and severity(depth) of flooding depend on the rela-tionship between a structure’s first floorelevation and the flood levels at the site.

E LEVAT ION OF STRUCTURES

Accurate data on each building’s elevationare critical for analysis. When elevations

OMB Requirements. . .

The Office of Management and

Budget (OMB) provides specific

guidance for doing a benefit-

cost analysis. OMB recommends

that analyses include compre-

hensive estimates of expected

benefits and costs to society

based on established definitions

and practices.

at a Glance

Table 1. Benefit-Cost Analysis Basics

��

E S T I M AT I NG DAMAG E S FLOOD RISK*FLOOD HAZARD DATA

x =

Annualized future

flood losses

Building damagesContents losses

+ Displacement costs

Dollar losses/flood event

Flood frequencyFlood dischargeFlood levels

+First floor elevations

Flood probability

*Annual average flood losses in dollars.

— Hugh Herring

Mayor of Geneva


BENEF IT -CO S T AN A LYS I S

are combined with flood hazard data, thesoftware determines how often a struc-ture will flood and how deep the waterwill be in different floods. It’s importantto understand that the lower a structure isin the floodplain, the more frequent andsevere the flooding will be at the site. Itmakes sense, then, that the best mitiga-tion projects will prevent the mostfuture damages where the risk of floodingis highest.

ESTIMATING DAMAGES

The next step in the analysis is to esti-mate the costs of damages in future floodsto buildings and contents, displacementof families and individuals, and disrup-tion of the local economy. Generally, localsources provide this information . For ex-ample, local officials often supply infor-mation on building size, construction type,and other data to help develop damageestimates. The software includes severalbuilt-in values for this information basedon insurance claims submitted to the Fed-eral Insurance Administration.

KEY CONCEPTS

Mitigation benefits accrue over the life ofthe project. Acquisition projects, like thatin Geneva, are considered a permanent so-lution to the flood problem. Damages af-ter an acquisition project are always zero:

the structures are no longer in the flood-plain, and the analysis estimates damagesif structures were to remain. For analysispurposes, the project was assigned a use-ful life of 100 years.

For a stormwater drainage project like theone in Elba, damages are reduced by themitigation project, but aren’t completelyeliminated (especially in large floods). Forsuch projects, the estimated reduction infuture damages is based on the performanceof the mitigation measure. The useful life-time of the project was estimated to be 30years.

Avoided damages, then, are the benefitsof the mitigation project. Federal regula-tions require that acquired properties bemaintained as open space for wetlands orfor recreational purposes.

For structures acquired in Geneva, thebenefits of avoided damages to buildingsand contents, as well as displacementcosts, were calculated using FEMA soft-ware and methodology. The graphic be-low shows the results page from FEMA’sbenefit-cost analysis software summariz-ing a project’s benefits and costs.

The next section takes a look at Elba andGeneva, and how they responded to dev-astating floods in 1990 and 1994.

Elevation & Flooding. . .

The lower a house sits in the

floodplain, the higher the

flood risk and the more fre-

quent and severe flooding will

be. For example, a house in a val-

ley whose first floor is 176

feet above sea level might flood

about once every 10 years. But

a nearby house on a hill with a

first floor elevation of 190

feet might flood once every

500 years. So acquiring struc-

tures that are deepest in the

floodplain offer the greatest

benefits.

an Example

Sample “Results” page from FEMA’s Benefit-Cost Analysis software.


THE 1990 & 1994 FLOODS

At the end of a week of rain andflooding in March 1990, about6,000 people in Alabama had lost

their homes or seen their property dam-aged. Hundreds more had to seek shelterin neighboring Georgia and the Florida Pan-handle. Some estimates placed damagesfrom the storms and flooding throughoutthe state at more than $100 million.

The hardship was summed up at the timeby Alabama governor Guy Hunt: “A life-time of hard work for some disappearedinto the raging floodwaters. A lot of ourpeople have never witnessed such devas-tation from floods before.”

Four years later, it was déjà vu for thepeople of southeast Alabama. In early July1994, Tropical Storm Alberto movedslowly inland, leaving a trail of floodingand destruction along the Pea andChoctawhatchee Rivers. Small townsalong these waterways like Elba andGeneva were hit particularly hard.

C I T Y OF ELBA

Originally named “Bridgeville,” after theferry that ran across the Pea River, Elbawas founded around 1840. The town,which is also the county seat of CoffeeCounty, is located in the fork betweenBeaver Dam Creek and the confluence ofWhitewater Creek and the Pea River. To-day Elba remains a small community of4,000 residents. Despite its size, however,the town is home to several manufactur-ers and industries.

Elba has a long history of flooding stem-ming from two different causes: 1) failureof the town’s protective ring levee, whichcauses major flooding throughout thedowntown area—as happened in 1990 andin 1998, and 2) stormwater accumulationwithin the levee, in the low-lyingsouthcentral and southwestern areas oftown—as happened in 1994.

“Our downtown area was the most

affected. Businesses outside the

levee were generally not af-

fected. The floods, before we

installed the pumps, lasted for

several days—the floodwaters

had nowhere to go. Businesses

could not get into their stores

to start cleaning up until the

floodwaters receded.”

In the 1930s, the Works Progress Admin-istration constructed a 3-mile long leveeenclosing three sides of the town. While itwas an effective measure at the time, to-day the aging levee is vulnerable in theevent of a major flood. In fact, the leveefailed during the March 1990 storm whenWhitewater Creek overtopped its banksand caused the worst flooding the townhas seen. Hundreds of buildings wereflooded, and damages ranged upwards of$10 million. It took weeks of around-the-clock pumping to remove floodwaters.

• Long history of flooding:1929, 1938, 1975, 1990,1994, and 1998

• Hundreds of structuresflooded, costing millions

• Up to 10 feet of water in1990; 6 feet in 1994

• Levee failed in ’90; storm-water trapped within in ’94

Elba Flooding. . . at a Glance

— Donnie Morrow

City Clerk, Elba

Source:FEMA

Source:FEMA

. . .and the same road under floodwaters in 1990.

A dry strip of road in Elba. . .


After the 1990 catastrophe, Elba repairedthe levee, which held during TropicalStorm Alberto in 1994. But while theflooding was much less severe than thetown experienced four years earlier, morethan 15 houses, a business, and a churchwere flooded from stormwaters trappedinside the levee.

ELBA’S DRAINAGE SYSTEM

To keep rainwater from pooling in thetown, Elba constructed culverts that di-rect the water back into the Pea River.However, when storms cause river levelsto rise four or five feet, outflow from theculverts is blocked by valves to preventriver water from backing up into the town.When this happens, stormwater accumu-lates inside the levee and floods homesand businesses.

After the 1994 flood, Elba applied for ahazard mitigation grant to install astormwater drainage system. FEMAapproved the grant application in July ofthat year. The system was built in 1997 bywidening an existing drainage channel andinstalling two pumps at low-lying pointsin the town’s southeast quarter. The pumps,designed to removewater quickly fromflooded areas, are eachcapable of moving17,500 gallons perminute (see picture).

CITY OF GENEVA

Located about 45miles downriverfrom Elba, the smalltown of Genevawas founded in the1830s at the junc-tion of the Choc-tawhatchee and PeaRivers.

T H E 1990 A N D 1994 F L O O D S

Today, Geneva is a thriving communityrich in tradition and civic pride. Althoughit’s a small town of about 4,700, Genevahas a wealth of industry and business op-portunities that draw workers from sur-rounding areas—making its employmentforce almost equal to its population.

Like Elba, Geneva has a long history offlooding. In 1861, the town was destroyedby a flood and relocated to higher ground.Since the turn of the century, Geneva hasbeen flooded four times. Three of thoseevents occurred in this decade.

Although not all residents of Geneva werehard hit in each flood, the small residentialarea of Baptist Bottoms has alwaysreceived the brunt of the damage. Accord-ing to the Geneva City Clerk, “with theexception of what they could carry outduring the evacuation, [Baptist Bottomsresidents] lost everything in the [1990 and1994] floods.”

THE BAPTIST BOTTOMS

ACQUISITION

To stem the cycle of disasters, Genevaapplied for hazard mitigation grant funds

to acquire structuresmost at risk. FEMAagreed to fund thebuyout of dozensof buildings withinthe floodway ofDouble BridgesCreek in BaptistBottoms. A numberof additional appli-cations are pending.

The next sectionsexplain the nutsand bolts of thebenefit-cost analy-ses conducted forboth communities’mitigation projects.

One of two pumps installed on Elba’s levee after the

1994 flood.

So

urce:

FEM

A

Geneva Flooding. . . at a Glance

• Long history of flooding

• Severe flooding in 1990 and

1994

• Hundreds of thousands of

dollars in damage

• Homes and property in Baptist

Bottoms wiped out


B E N E F I T- C O S T A N A LY S I S :

E L B A

“In the ’90 flood, emergency

crews used two gator pumps at a

cost of $83,000 and took more

than one week to reduce flood-

waters [to the point] where

people could start cleaning up.”

After Tropical Storm Alberto, stafffrom FEMA’s regional office inAtlanta, Georgia worked with lo-

cal Elba officials to determine the best ap-proach for hazard mitigation. FEMA’sbenefit-cost analysis determined that thestormwater pumping project the townproposed was cost-effective. The projectwas designed to mitigate damage from fre-quent stormwater flooding, such as thetown experienced in 1994. This sectionexplains how the revised and updatedanalysis on the project was conducted.

G AT H E R I N G D ATA

The first step in this benefit-cost anlysisis to gather flood hazard data. Elba’s is aspecial case because the town suffers fromtwo types of flooding. In the first type,the levee fails when waters from thenearby streams reach critical level. In thesecond case—which the analysis ad-dresses—the river level is too high to per-mit Elba’s drainage system to work, caus-ing water to back up inside the levee.

Flood hazard data (frequency of floodingand flood levels) are often derived fromengineering studies. But for Elba, thesedata were provided by local officials andinterpolated estimates. For example,thunderstorms cause minor flooding in

streets and yards in the lower-lying areasof town about three times a year. Damagefrom this type of flooding is relatively mi-nor, but it does lead to cleanup costs. Largerfloods take place every five years or so andresult in shallow flooding in the first floorsof roughly ten houses on average. And forthe largest floods—500-year floodevents—flooding would affect about 70homes. These estimates provided the basisfor predicting the levels of flooding (i.e.,10-, 25-, 50-, 100-, and 250-year floods).

The next step in the analysis involves de-termining damages expected for each floodfrequency. This information, which wasbased on historical observations of localElba officials and FEMA estimates, cov-ers building and contents damages, dis-placement costs, and clean-up and emer-gency services costs (see Table 1).

Table 1. Data Sources – Elba Analysis

The category. . . . . . and its value . . . . . .came from

Replacement Value of Buildings $50/sq. ft. Local officials

No. of Buildings 0-70 Local officials

Building Damages $0-$945,000 FEMA estimate

Building Size 1500 sq. ft/house Local officials

Contents Value $20,000/house FEMA estimate

Contents Damages $0-378,000 FEMA estimate

Cleanup/Emerg. Assistance1 varies/year FEMA estimates

1Ranges from $5,000/year for small floods to over $300,000/year in very large floods.

Elba Analysis. . . at a Glance

— James Grimes

Mayor of Elba

•Project Cost: $391,114

•Benefits: $517,293

•Benefit-Cost Ratio: 1.32


B ENEF IT -COST ANALYS I S : EL B A

DAMAGES BEFORE MITIGATION

Benefit-cost analysis compares damagesthat would be expected before and aftermitigation to determine if a project is cost-effective. Table 2 shows that the minorflooding that occurs a few times a year

For example, the minor floods that hap-pen about once every five years (andcause shallow flooding in several homes)result in contents and building damages,and emergency costs of $109,500. But alarge-scale flood can cause more than $1.6million in damages.

DAMAGES AFTER M ITIGATION

As you can see in Table 3 below, Elba’sstormwater pumping system will preventall damages in floods that occur less thanonce every 50 years. But unlike an acqui-sition project (where the flood risk is re-duced to zero), the pumping systemdoesn’t eliminate the potential for flood-ing damage completely.

Flood Projected Damages Total

Frequency Building Contents Other1 Damages

1-25 $0 $0 $0 $0

50 $50,000 $20,000 $30,000 $100,000

100 $90,000 $36,000 $46,667 $172,667

250 $133,333 $50,000 $67,500 $250,833

500 $315,000 $126,000 $110,000 $551,000

1Includes emergency clean-up costs.

Table 3. Flood-Frequency Damage Estimates After Mitigation

1Includes emergency clean-up and displacement costs.

Table 2. Flood-Frequency Damage Estimates Before Mitigation

Flood Projected Damages Total

Frequency Building Contents Other1 Damages

1 $0 $0 $5,000 $5,000

2 $0 $0 $10,000 $10,000

5 $67,500 $27,000 $15,000 $109,500

10 $80,000 $33,000 $20,000 $133,000

25 $100,00 $40,000 $55,000 $195,000

50 $150,000 $60,000 $90,000 $300,000

100 $270,00 $108,000 $140,000 $518,000

250 $400,000 $150,000 $202,500 $752,000

500 $945,000 $378,000 $330,000 $1,653,000

causes limited clean-up damages(“Other”). However, as the floods getworse—beginning at the 5-year level—damages to buildings and their contentsincrease, resulting in much higher damagetotals. The analysis considers more de-tailed damage estimates for larger floods.

The analysis reveals that 50-year floodsand larger would overwhelm the pumps’ability to drain floodwaters. Still, thedamages from larger floods will be reducedby about 66% over the “before” mitiga-tion estimates.

This analysis clearly shows that the pumpproject will substantially reduce futureflood-related damages and losses in Elba.

(For more detail, see the Elba chapter inthe Appendix to this report.)

But regardless of how accurate an analy-sis may seem on paper, the most persua-sive case for mitigation is made when areal-world flood event puts the project tothe test. The section on the flooding inMarch 1998 describes how the Elba projectheld up in just such an event.


B E N E F I T- C O S T A N A LY S I S :

G E N E V A

In the aftermath of the 1994 flood,Geneva officials developed what couldbe considered a model hazard mitiga-

tion project. They began an aggressive cam-paign to convince homeowners in theflood-prone Baptist Bottoms area to selltheir homes and relocate out of the flood-plain. Eventually, they submitted a grantapplication to FEMA for the acquisitionof 54 homes.

An initial benefit-cost analysis determinedthat the project would be cost-effective.All of the structures lay deep in the flood-plain, and it was clear that damages fromrepeated flooding in the future would takea heavy toll on the community.

Of the original 54 structures included inthe application, 30 were actually acquiredand removed before the March 1998 flood.A revised and updated benefit-cost analy-sis for this group found that the acquisi-tion was even more cost-effective than ini-tially projected.

The data used in the revised benefit-costanalysis came from a 1987 Flood Insur-ance Study for the City of Geneva. Firstfloor elevation (FFE) flood depths wereprovided by local officials.

DAMAGES BEFORE M ITIGATION

The next step in the analysis is to gatherthe data needed to estimate damages tobuildings and their contents and displace-ment costs in future floods. These datainclude the number, size, and replacementvalue of buildings, the value of their con-tents, estimated costs for temporary liv-ing quarters for displaced residents, andlost business income. The values andsources of this information are summa-rized in Table 5 below.

*From FIS flood profile graph for Double Bridges Creek.

The data category. . . . . . and its value . . . . . .came from

First Floor Elevations (FFEs) 95’ to 98’ above sea level Local officials

Building Replacement Value (BRV) $45 (sf) Local officials

$25 (sf for mobile homes)

Building Size various Local officials

Building Type 1 story w/o basement Local officials

mobile home

Demolition % 25% FEMA estimate

Contents Value $20,000/house FEMA minimum

Displacement Costs (Rent) $0.50 (sf/month) Local data

Displacement Costs (Other) $250 (residence/month) FEMA estimate

Displacement Costs $200 (one time) FEMA estimate

Project Costs Per structure City data

Demolition Costs $746 (avg/structure) Application

Table 5. Data Sources – Geneva Analysis

“The residents of Baptist Bottoms

were the hardest hit in the 1990

and 1994 floods. With the excep-

tion of what they could carry out

during the evacuation, they lost

everything in those floods. A few

moved out after 1990 and all but

six moved out after 1994.”Geneva Analysis. . .

at a Glance

FLOOD

HAZARD DATA

The first step indoing a benefit-cost analysis in-volves gatheringflood hazard data.Typically, infor-mation on floodhazards for a com-munity is takenfrom a FEMAFlood InsuranceStudy.

— Lisa Johnson

City Clerk, Geneva•Project Cost: $672,558

•Benefits: $1,329,373

•Benefit-Cost Ratio: 1.98

Frequency Discharge Elevation*

(years) (cfs) (feet above sea level)

10 8,700 95.3

50 16,000 100.0

100 20,000 102.1

500 32,000 107.8

Table 4. Flood Hazard Data – Geneva


B ENEF IT -COST ANALYS I S : GENEVA

FEMA’s benefit-cost software combinesthese data with flood hazard data and build-ing elevations. The result is a clear pictureof how damages increase as flood depthsincrease.

AN A LYS I S AND CONC LU S I ON S

Once all damage data are gathered and en-tered into the benefit-cost analysis soft-ware, a summary is generated that showshow severe future flood losses would beif the structures were to remain. That is, ifthe project to remove the structures werenot implemented.

It bears repeating that the mitigationproject—acquisition and removal of struc-tures—completely eliminates the poten-tial for future losses. The benefits of the

in projected benefits. On the other hand,the structures that would have up to sevenfeet of flooding in a 100-year flood (toptwo rows) yield the most benefits—andyield the highest benefit-cost ratios.

The benefits and costs for each group ofstructures at a given elevation are addedtogether for total costs and benefits of the30 acquired structures. The estimate offuture benefits is based on probable fre-quencies and severities of future floods inGeneva. Total project costs were roughly$670,000; total benefits were estimated at$1.3 million. With a benefit-cost ratio of1.98, this project is considered highlycost-effective. (For more detail, see thechapter on Geneva in the Appendix to thisreport.)

mitigation project are the damages avoided,as listed in Table 6 below. These resultsfrom FEMA’s benefit-cost analysis forGeneva show the relationship among allkey categories that are used to determineproject cost-effectiveness.

The table provides a detailed breakout ofthe benefit-cost analysis for Geneva. Thelevel of flood risk for a given house is de-termined by the structure’s elevation(FFE) relative to the 100-year flood level(BFE) at that site. For example, a homewhose FFE is seven feet below the BFE(FFE-BFE = -7 feet) will have seven feetof water above the first floor in a 100-year flood. The table shows that struc-tures that had the lowest risk of flooding(bottom two rows) would offer the least

*MH: mobile home**SS: single story house; no basement

1 No. of Structures. Number of structures grouped by elevation (not shown). Example: seven structures (fourth row) were at the same elevation.

2 FFE-BFE (Feet). The elevation of a structure’s first floor in a 100-year flood (“base flood”). Example: the fourth row shows data for seven single story

houses without basement, all with FFEs five feet below the 100-year flood level.

3 Total Square Feet. Square footage of the building(s).

4 Mitigation Costs. The cost to buy out the structure(s) in this elevation group.

5 Projected Benefits. Damages to structures broken out by category if they had remained in the flood zone (i.e., had not been acquired and removed).

(NOTE: “Displacement” refers to temporary rent and other related costs.)

6 Total Benefits. Total projected damages to structures if they had remained in the flood zone (i.e., had not been acquired and removed).

7 Benefit-Cost Ratio. “Total Benefits” divided by “Mitigation Costs.” A ratio of 1.0 or above means the mitigation measure is cost-effective.

1 2 3 4 5 6 7

No. of FFE-BFE Total Mitigation Projected Benefits Total Benefit-

Structures (Feet) Sq. Feet Costs Building Contents Displacement Benefits Cost Ratio

2 MH* -7 1,726 $18,152 $33,645 $22,781 $13,546 $69,972 3.85

16 SS** -7 17,660 $338,664 $619,649 $182,248 $126,737 $928,634 2.74

1 SS -6 1,040 $38,996 $26,112 $8,066 $5,270 $39,448 1.01

7 SS -5 7,256 $164,162 $131,137 $38,660 $26,747 $196,544 1.20

4 SS -4 5,068 $112,584 $66,263 $15,700 $12,812 $94,775 0.84

30 32,750 $672,558 $876,806 $267,455 $185,112 $1,329,373 1.98

Table 6. Geneva Benefit-Cost Analysis Results


T H E M A R C H ’ 9 8 F L O O D S

In the first week of March 1998, aheavy storm system from the Gulf ofMexico moved inland across the south-

eastern United States. Torrential rainsswept through the region and caused seri-ous flooding in several Alabama counties.

The flooding not only damaged hundredsof homes and businesses, it also took aserious toll on infrastructure: severalbridges and culverts were overwhelmed,roads were washed out, emergency ser-vices were delayed, and water treatmentfacilities were damaged.

ONLY ROOFTOPS AND WINDOWS

VISIBLE

Four people died in the flood, which aRed Cross worker in the area said re-minded her of “the Midwest floods, whereyou [only saw] the top of the roof or thewindow.”

“Damages [from the March 1998

flood] were significantly re-

duced by the recovery and miti-

gation measures that were imple-

mented after the 1994 floods.”

—The President’s Long-Term

Recovery Action Plan

Alabama, March 1998

banks, and the levee surrounding the townfailed. Flood depths in the downtown areawere as high as five feet, and half the town’sresidents were evacuated.

Governor Fob James toured the scene in aboat, and ordered the National Guard tohelp with sandbagging and patrol down-town Elba in pontoon boats. Water levelsinside the levee were over two feetthroughout most of the area. The newpumps were able to drain the area of wa-ter in approximately four and a half days.Had the pumps not been available, itwould have taken natural drainage andsmaller pumps as long as eight or ninedays to completely drain the area.

F L OOD DAMAGE : G E N E VA

For the citizens of Geneva, it was anothernightmare come true. Three days of risingfloodwaters caused Double Bridges Creekto overrun its banks, and the areas lyingoutside the town’s protective levee wereflooded. The Choctawhatchee and Pea riv-ers both peaked at over 35 feet—approximately 13 feet above flood stage.

Compared with 1994, Geneva suffered farless property damage, due in part to themitigation measures FEMA carried outafter the last flood. Still, over 50 familieswere evacuated, and damages to the cityexceeded $100,000.

Buildings and a stretch of road peak through the

flooding in Geneva, 1998.

On March 9 the state was declared a di-saster area and 12 counties qualified forFederal emergency assistance. Those eli-gible included Elba and Geneva.

1998 FLOOD DAMAGE : ELBA

The small community of Elba was devas-tated again in the third disastrous flood inten years. Eight inches of rain causednearby Beaver Dam Creek to overtop its

*For a single flood event in March 1998.

Avoided Damages*. . .

Elba


•Avoided Damages: $131,866

Geneva


•Avoided Damages: $1,434,053

at a Glance


THE MARCH ‘98 FLOODS

A VO I D E D D A M AG E S : E L B A

Elba’s pump system reduced by half thetime it took to drain the water from in-side the levee. And although thedamages avoided were less dramatic thanfor other projects—such as the acquisi-

tion project in Geneva—the savings werestill significant.

Total damages in the 1998 flood wereestimated at nearly $4 million. Most ofthe costs resulted from damages to build-ings and contents, totaling roughly$3,110,000. Temporary housing for thosedisplaced by the flood, emergencyclearnup, and business losses made upmost of the rest of the damages.

All told, Elba’s pump system saved$130,000 in damages from the March 1998flood. While this figure doesn’t seem veryhigh compared to the total damages, thepoint to remember is that over the 30-year life of the project the system willlikely generate savings well beyond thecost of the project.

Damage Category Estimate

Building Damages $62,200

Contents Damages $19,000

Displacment Costs $24,000

Cleanup/Emergency Management $20,000

Business Income Losses $6,666

Total $131,866

Table 7. City of Elba

Mitigation Project Avoided Damages – March ’98 Flood

AVO I D ED DAMAGES : G ENEVA

The buyout of 30 homes after the 1994flood proved to be an effective investmentin Geneva. FEMA’s benefit-cost analysissoftware determined that for an upfrontcost of approximately $672,000 to acquireand remove flood-prone properties, over$1.4 million in damages and losses wereavoided. All of the acquired structures laydeep in the floodplain, and would havebeen flooded had they remained in the

flood-risk zone. If the Baptist Bottomsarea had been redeveloped after the 1994floods, many houses would have been se-verely damaged or destroyed in the floodsof March 1998.

This illustration of avoided damagesemphasizes a very important point forhazard mitigation planning: the biggestbenefits come from acquiring structuresat highest risk—that is, buildings that aredeepest in the floodplain.

Table 8. City of Geneva

Mitigation Project Avoided Damages – March ’98 Flood

No. of First Floor 1998 Flood Avoided Damages Total Avoided

Structures Elevation Above FFE Building Contents Disp. Damages

2 MH* 95 4 $43,150 $17,400 $16,983 $77,533

16 SS** 95 4 $794,700 $139,200 $159,298 $1,093,198

1 SS 96 3 $46,800 $8,100 $9,568 $64,468

7 SS 97 2 $71,834 $46,200 $23,988 $142,022

4 SS 98 1 $31,928 $16,800 $8,104 $56,832

30 $988,412 $227,700 $217,941 $1,434,053

*MH: mobile home**SS: single story house; no basement


C O N C L U S I O N

Natural disasters are a fact of life.Unfortunately, it’s hard to envi-sion a world where disasters don’t

bring some degree of suffering. But whiledisasters can’t be avoided altogether, thedamage they cause can be reduced.

That’s why FEMA’s Hazard MitigationGrant Program was created. With fore-sight and proactive planning, people wholive in disaster-prone communities nowhave the means to do something aboutnatural disasters.

The grant program has existed for only afew years. But in an effort to make it asefficient as possible, it’s important toevaluate the program to see how well it’sworking. This is one of the few times sincethe inception of the program that FEMAhas revisited several communities to mea-sure actual dollars saved due to hazardmitigation.

This economic analysis of flood mitiga-tion projects in southeast Alabamareviewed both the original estimates ofhow much could be saved in avoidedfuture damages in two Alabama commu-nities—as well as the supporting data toshow just how much was actually savedin a single, real-world flood event.

The results are impressive. In the firstflood since the FEMA-funded mitigationproject was put in place, the small com-munity of Elba realized $130,000 inavoided damages. And through the acqui-

sition and removal of 30 at-risk homesfrom the floodplain, the city of Genevasaved over $1.4 million in avoided dam-ages in the first flood since the mitigationproject was carried out.

THE BOTTOM L INE

This report has shown that hazard miti-gation can be a cost-effective way to helpreduce the toll of future disasters. Andwhile it may not be a panacea, it’s a bigstep in the right direction.

Elba and Geneva are two communitiesthat have taken that first step. Althoughthey’ll undoubtedly suffer throughflooding in the future, they have begunto make themselves more disaster-resistant. Both cities will continue toreap benefits from their mitigationprojects for years to come. And thatdoesn’t just save money. It also im-proves the quality of life for people whoknow these places not as “flood-prone”communities, but as home.

“The buyout of Baptist Bottoms in

Geneva prevented those families

that participated from being

flooded again in ’98. It also en-

abled emergency crews to work

on flood control and less on

evacuations.”

Hazard Mitigation. . .

Hazard mitigation projects make

sense when the damages avoided

are higher than the costs of the

measure. Such projects cost-

effectively reduce or eliminate

the damages, losses, and hard-

ship of repeated flooding.

Why it Works

• For more information about the Hazard MitigationGrant Program, contact your state emergencymanagement agency.

• To learn more about hazard mitigation, or to down-load an online version of this document, visit FEMA’sweb site at http://www.fema.gov.

• For an in-depth review of the analyses presentedhere, see the Appendix to this report.

— Roy Powell

Resident of Geneva

Source:

FEM

A

H A Z A R D

M I T I G A T I O N

H A Z A R D

M I T I G AT I O N

AT WO R K :

T W O A L A B A M A C O M M U N I T I E S

Federal Emergency Management Agency

F EMA

Each year natural disasters cost taxpayers mil-lions of dollars. But the damage doesn’t end

there. Disasters leave in their wake human miseryand suffering that can’t be measured in dollars. Asfootage of disasters is broadcast to the homes ofmillions, a question on people’s minds is: can’tsomething be done about this?

The answer is yes. Something is being done. It’scalled hazard mitigation, and FEMA is leadingthe way to help communities make themselves moredisaster-resistant.

This brochure reviews two mitigation projects inthe communities of Elba and Geneva, Alabama.Both have a history of flooding, and both receivedgrants to carry out mitigation projects after mas-sive flooding in 1990 and 1994. And when bothcities were flooded again in March 1998, theprojects saved hundreds of thousands of dollarsin damages.

FEMA funds hazard mitigation projects throughits Hazard Mitigation Grant Program. The pro-gram targets communities prone to repetitivenatural disasters. Flood projects, which rangefrom elevating buildings to removing themaltogether, reduce or eliminate hazard risks.

One of the key criteria for a hazard mitigationproject to qualify for funding is that it must becost-effective. FEMA uses benefit-cost analysissoftware to determine if a project’s benefits—avoided losses in future disasters—outweigh itscosts. If a hazard mitigation project that costs $1million today is estimated to save $2 million inpotential damages tomorrow, the project is cost-effective and worth funding.

This specialized software calculates how often andhow bad damages will be at the project site basedon flood hazard data and building elevations. Theend result of the analysis is called a benefit-costratio. The benefit-cost ratio is determined by di-viding estimated project benefits by total projectcosts. A project with a benefit-cost ratio of 1.0 orgreater is considered cost-effective.

T H E 1 9 9 0 A N D

1 9 9 4 F L O O D S

By the end of a week of rain and flooding in March1990, about 6,000 people in southeast Alabamahad lost their homes or seen their property dam-aged. Estimates placed damages throughout thestate at more than $100 million.

In July 1994, Tropical Storm Alberto moved inlandover southeast Alabama, leaving a trail of destruc-tion along the Pea and Choctawhatchee Rivers. Thesmall communities of Elba and Geneva were amongthe many devastated by Alberto’s floods.

Located in the fork between Beaver Dam Creekand the confluence of Whitewater Creek and thePea River, Elbahas a long his-tory of repeatedflooding. In 1990,and again in 1998,the protectivelevee surround-ing the townfailed when swol-len streams near-by overran theirbanks. Althoughthe levee held in 1994, failure of the town’sstormwater drainage system led to flooding of thedowntown area inside the levee. After the 1994flood, Elba applied for a hazard mitigation grantto install a stormwater pumping system insidethe levee enclosure.

Like Elba, Geneva also has a long history of flood-ing: since the turn of the century, it has beenflooded four times. Three of those events occurredin the past eight years: in 1990, 1994, and 1998.To stem the cycle of disasters, Geneva applied forand was granted funds to acquire and removedozens of buildings from the floodway of DoubleBridges Creek, in the flood-prone residential areaof Baptist Bottoms.

BENEFIT-COST

ANALYSIS

ELBA AND

GENEVA, ALABAMA

GENEVA ACQUISITION

PROJECT

ELBA STORMWATER

PUMP PROJECT

CAN’T SOMETHING

BE DONE?

hazard mitigation is an investment

made today to reduce the toll from

disasters tomorrow.

TROPICAL STORM

ALBERTO

In 1988, the HMGP was incorpo-

rated into the Stafford Act, the

law that governs FEMA’s disaster

recovery activities.

HAZARD MITIGATION

GRANTS

B E N E F I T- C O S T

A N A L Y S I S

After Tropical Storm Alberto in 1994, FEMAregional staff worked with local officials in

Elba and Geneva to determine the best approachfor hazard mitigation.

Elba proposed a stormwater drainage project toreduce damage from frequent stormwater floodingwithin the levee. Geneva applied for a grant tofund the acquisition and removal of a number ofstructures in the floodway outside its levee. TheFEMA evaluation determined that both projectswere cost-effective, and would yield significantbenefits in future floods.

In the first week of March 1998, a heavy stormsystem from the Gulf of Mexico moved inland

across the southeastern United States. Torrentialrains inundated the area and caused serious flood-ing in a number of Alabama counties.

The flooding not only damaged hundreds of homesand businesses, it also took a heavy toll on infra-structure: several bridges and culverts were over-whelmed, roads were washed out, emergency ser-vices were delayed, and water treatment facilitieswere damaged. On March 9 the state was declareda disaster area, and 12 counties qualified for emer-gency assistance from FEMA.

T H E M A R C H ’ 9 8

F L O O D S

Natural disasters are a fact of life. But whilethey can’t be avoided, some of the damage

they cause can be.

For an upfront cost of approximately $390,000 toinstall a stormwater drainage system for small-to-moderate floods, the small community of Elba re-alized over $130,000 in avoided damages in thefirst flood since the project was carried out.

ANALYSIS

RESULTS

BENEFITS &

COSTS

DAMAGES AVOIDED

IN 1998

A RECURRING

N IGHTMARE

Geneva’s experience underscores the cost-effectiveness of hazard mitigation even more. Fora cost of $670,000, over $1.4 million in damageswere avoided during the March 1998 floods.

Although hazard mitigation is not a panacea, it’sone way communities can help themselves becomemore disaster-resistant. Elba and Geneva havemade a start. Both cities will continue to reap ben-efits from their mitigation projects for years to come.And that doesn’t just save money. It also improvesthe quality of life for people who know these placesnot as “flood-prone” communities, but as home.

Total costs for the Elba project were $391,114 toinstall two pumps and widen an existing drain-age channel to create a floodwater retentionpond. This system will prevent all damages infloods that occur less than once every 50 years.But unlike an acquisition project where the floodrisk is reduced to zero, the pumping systemdoesn’t eliminate damages completely. The analy-sis reveals that flood events at the 50-year leveland larger would overwhelm the pumps’ capac-ity. Still, damages from larger floods will be re-duced by about 66% over the “before mitiga-tion” estimates, because the pumping system willlower water depths and the area flooded.

The acquisition and removal of 30 flood-pronestructures in Geneva was considered highly costeffective. This was due largely to the fact that allof the structures were low in the floodplain andsubject to serious, repetitive flooding. Total costsfor the project were $672,558. Total benefits forthe lifetime of the project (100 years for analysispurposes) were estimated at $1,329,373. This fig-ure includes damages to the structures and build-ing contents, as well as displacement costs.

While these mitigation projects promised sig-nificant benefits in future floods, it remained tobe seen just how cost-effective they would provein the real world. The first test came sooner thanexpected in the region’s third disaster of the de-cade: the flooding of March 1998.

Before hazard mitigation grant

applications can be approved for

funding, OMB regulations require

them to be cost-effective.

Avoided Damages – March ’98

ElbaProject Cost: $391,114

Avoided Damages: $131,866

GenevaProject Cost: $672,558

Avoided Damages: $1,434,053

A V O I D E D

D A M A G E S

A STEP IN THE

RIGHT DIRECTION

“Anytime there was a flood, the

residents in Baptist Bottoms were

the hardest hit. . . Most of them

participated in the buyout program

after the ’94 floods and have now

been relocated.”— Hugh Herring

Mayor of Geneva

Elba was devastated again in the third disastrousflood event in ten years. Eight inches of raincaused Beaver Dam Creek to rise over its banks,and the levee surrounding the town failed. Flooddepths in the downtown area were as high as fivefeet, and half the town’s residents were evacu-ated. Water levels inside the levee reached depthsup to 2.25 feet. The new pumps were able to drain

the water in aboutfour and a half days.If the pumps hadn’t

been available, itwould’ve takennatural drainageand temporary pumps as long as nine days to com-pletely drain the area.

For the citizens of Geneva, it was another night-mare come true. Three days of rising floodwaterscaused Double Bridges Creek to overrun itsbanks, and the areas outside the town’s leveewere flooded. The Pea and Choctawhatchee riv-ers both peaked at over 35 feet—13 feet aboveflood stage. Compared with 1994, Geneva suf-fered less property damage, due in part to the miti-gation measures. Still, over 50 families were evacu-ated, and damages to the city exceeded $100,000.

Source:

FEM

A

’98 FLOOD DAMAGE:

ELBA

’98 FLOOD DAMAGE:

GENEVA

To learn more about hazard miti-

gation, or to download this full

report online, visit FEMA’s web

site at http://www.fema.gov.

hazard mitigation at workmitigation.eeri.org/files/resources-for-success/00044.pdfthe only 100%...

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