a study of droughts in texas - twdb bulletin 5914 - december 1959

8/2/2019 A Study of Droughts in Texas - TWDB Bulletin 5914 - December 1959

1/81

TEXAS BOARD OF WATER ENGINEERSDurwood Manford, Chairman

R. M. Dixon, MemberO. F. Dent, Member

..... -.. ... Oil(8)-. .. ......:.....

BULLETIN 5914A STUDY OF DROUGHTS

IN TEXAS

Prepared byThe Late Robert L. Lowry, Jr .

Consulting Surface Water Hydrologistfor

Texas Board of Water EngineersDecember 1959

. Pric. $1.00(TO THOSE NOT ENTITLED TO FREE DISTRIBUTION)


2/81

TEXAS BOARD OF WATER ENGINEERSDun,ood Manford, ChairmanR. M. Dixon, Member

( I. F. Dent , Member

BULLETIN 5914

A STUDY OF DROUGHTSIN TEXAS

Prepared byThe la te Robert L. Lowry, Jr .Consulting Surface Water HydrologistforTexas Board of Water EngineersDecember 1959

Price $1.00(To Those Not Entit led to Free Distr ibution)Those enti t led to free dist r ibut ion are governmentalagencies and off ic ia l s .


3/81

TArLE OF CONTENTSPage

FOREWORD----------------------------------------------------------------- 1ACKUaJLEDGEMENTS--------------------------------------------------------- 2INTRODUCTION------------------------------------------------------------- 3AVAILAE,LE DATA----------------------------------------------------------- 5VARIATION IN ANNUAL RAINFALL--------------------------------------------- 6EXTENT AND SEVERITY OF DROUGHTS-------------------- ---------------------- 9

Determination of Drough t Per iods----- ------ ------ ------ ------- ------ -- 9Average Rain fa l l - - -- - -- -- - -- - -- -- - -- -- - -- - -- -- - -- -- - -- - -- -- - -- -- - -- 11Rainfall Defic ienc ie s-- - -- - -- -- - -- - -- -- - -- -- - -- - -- -- - -- - -- -- - -- - --- 11Descriptions of Historical Droughts-------------------------------- 11

Drough t of 1891 - 1893------------------------------------------ 13Drough t of 1896 - 1899------------------------------------------ 13Drought of 1901------------------------------------------------- 14D rough t of 1909 - 1912------------------------------------------ 15Drough t of 1916 - 1918------------------------------------------ 15Drough t of 1924 - 1925------------------------------------------ 16Drough t of 1933 - 1934------------------------------------------ 16Drough t of 1937 - 1939------------------------------------------ 17Drought of 1950 - 1952------------------------------------------ 17Drough t of 1953------------------------------------------------- 17Drough t of 1954 - 1956------------------------------------------ 18

Summary of Eleven Droughts Since 1889------------------------------ 18Severity of Drough ts-- - -- -- -- - -- -- -- - -- -- - -- -- -- - -- -- -- - -- -- -- - -- -- 20

TEMPORARY SHIFTS IN CLIMATE DURING DROUGHTS------------------- ----------- 20EFFECTS OF DROUGHT ON TEXAS gCONOMY--- -------------- --- ------------------ 28

Agricultural Losses-- ---- ---- ---- --- ---- ---- ---- ---- ---- ---- ---- ---- -- 28


4/81

TABLE OF CONTENTS (Continued)Page

Winds----------------------------------------------------------------- 30Drought Aid----------------------------------------------------------- 31Effects on Municipalities--------------------------------------------- 33Effects on Industry--------------------------------------------------- 33Effects on Irrigation------------------------------------------------- 34Effects on Hydroelectric Power Production----------------------------- 37Effects on Navigation------------------------------------------------- 38Effects on Recreation--- --- . - - ------------------------------------ ----- 38

EFFECTS OF DROUGHT ON WATER SUPPLIES------------------------------------- 38General--------------------------------------------------------------- 38Effects on Municipal Water Supplies----------------------------------- 41Effects on Industrial Water Supplies---------------------------------- 45Effects on Irr igat ion Water Supplies---------------------------------- 49Effect on Water Supplies for Hydroelectric Power---------------------- 49Effects on Navigation Water Supplies---------------------------------- 53Effects on Recreation Water Supplies---------------------------------- 53

CONSIDERATION OF PAST DROUGHTS IN THE DESIGN OF WATER SUPPLY PROJECTS---- 55General--------------------------------------------------------------- 55Municipal Water Supplies---------------------------------------------- 56Industrial Water Supplies--------------------------------------------- 56I r ~ i g a t i o n Water Supplies--------------------------------------------- 57Hydroelectric Power Supplies------------------------------------------ 59Water Supplies for Navigation------------------- ..--------------------- 59Recreation Water Supplies--------------------------------------------- 60Effect of Watershed Changes on Water Supplies------------------------- 60Additional Considerations -.- -- - -- ----- -- --- - - - - - -- - - - -- - - - - - - - --- -- -- -- 61


5/81

TABLE OF CONTENTS (Continued)

WHAT CAN BE DONE ABOUT FUTURE DROUGHTS----------------------------------- 63FUTURE DROUGHTS---------------o------------------------------------------- 67LIST CF REFERENCES----------- ------------------------------------------- 69APPENDIX A--- - - - - - - - - - - - - - - - -- - - - - - - - - - -- - - - - - - - - -- - - - - - - - - - -- - - - - - - - - - -- 71BACKGROUNDS OF ECONOMIC DISTRESS IN THE GREAT PLAINS--------------------- 71

TABLES

1 Rainfall Variation over Texas------------------------------------- 102 Comparison of Average Rainfal l f or Two Periods at Control

Stat ions---------------------------------------------------------- 123 Major Droughts in Texas Their Duration and Extent----------------- 214 Comparison of Rainfall in Drought Years with the Long-Time

Average Rainfa l l - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 225 Order of Severity of Droughts as Indicated by Deficiencies ofof Rainfall in Percentage of the Mean Annual Rainfall------------- 236 Comparison of Mean Annual Temperatures Average for 1924-1957 vs.Drought Years Since 1924 --- - - - - - - -- - - - - - - - - - -- - - - - - - - - - -- - - - - - - - - - 267 Water Shortages in Lower Rio Grande Valley---- - - - - - - - - - - - - - - - - - - - - 368 Average Annual Runoff in Percentage of the Mean------------------- 409 Reservoir Storage Reduction in Time of Drought-------------------- 42

10 Number of Months Texas Runoff Mentioned in Water ResourcesReview----- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 43

11 Municipalities Using E n ~ r g e n c y Sources of Supply, July 1, 1953---- 4612 Municipalities Rationing Water, 1953------------------------------ 4713 Communities Hauling Water, 1953----------------------------------- 4714 Municipalities Supplementing Water Supply During Recent Drought,and Municipalities Hauling Water During Recent Drought------------ 4815 Hydroelectric Power Generated at Possum Kingdom Reservoir Unit

Brazos River------------------------------------------------------ 51


6/81

TABlE OF CONTENTS (Continued)

16 Hydroelectric Energy Generated by Four Lower Colorado RiverAuthority Units - - - - - - - - - - - -- - - - - - - - - - -- - - - - - - - - - - -- - - - - - - - - - -- - - - - 5217 Hydroelectric Energy Generated by Units on Guadalupe andDevils Rivers----------------------------------------------------- 54

FIGURES

1 Annual Rainfall for Four Areas of Texas---------------------------

PLATES

7

FollowsI Accumulated Deficiency of Rainfall in Inches During Period1891-1893 --- - - - - - - - - - - -.---- -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ----Pg. 14I I Accumulated Deficiency of Rainfall in Inches During Period

1896-1899-- -- - - - - - - - -- -.----- ---------- - - - - - - - - - - ---- - --- -- ----- -Plate II I I Accumulated Deficiency of Rainfall in Inches During Period

1901-- -------- - --- ----- . - ------------------------------------- -- -Plate I IIV Accumulated Deficiency of Rainfall in Inches During Period1909-1912-- - -- - -- - - - -- - .. - - - - - - -- - -- - -- - - -- - - - - - - - - - - - -- - - - - - - - - - Pg. 16V Accumulated Defic iency of Rainfall in Inches During Period

1916-1918------ -------- .--- - - - - - ----- -- - - - - - - - - - - - - - - - - - - - - - - ----Plate IVVI Accumulated Deficiency of Rain fa ll in Inches During Period1924-1925 -- - -- - -- - - - - - - .. - - - - - - - -- - - - - - - - - - - - - - - - ---- -- -- - - - - - - - - P late VVII Accumulated Deficiency of Rainfall in Inches During Period

1933-1934-------------------------------------------------------Plate VIVIII Accumulated Deficiency of Rainfall in Inches During Period1937-1939-------------- -----------------------------------------Pg. 18IX Accumulated Deficiency of Rainfall in Inches During Period

1950-195 2---- - - - - - - - -- - -- - - - - - - - - - - -- - - - - - - - - - -- - - - - - - - - - -- - - - -Pla te VIIIX Areas with Deficient and Surplus Rainfall in 1953---------------Plate IXXI Accumulated Deficiency of Rainfa ll in Inches During Period1954-1956 -- - - - - - - -- - - - - . - -- - - -- - - - - -- - - - - - - - - -- - - -- - - -- - -- ---- -- -P late X


7/81

FOREWORDDroughts are one of the natural climatic phenomena which result when

ra infa l l i s below normal. Not every period of low ra infa l l , however, can beclassed as drought. I t is only when the deficiencies in ra infa l l are great orproloLged, that the land is experiencing a drought. Droughts are not somethingnew - man has had to contend with them throughout his existence.As Tannehi ll ( se e ref . 1) so aptly put i t :

"Drought belongs in that class of phenomena which a re popular lyknown as I spells of weather I . A drought is a spell of dry weather.Drought is unique among spells of weather; i t creeps upon us gradually,almost mysteriously, but i t s consequences are a terrible real i ty."Early recorded history makes frequent reference to droughts and resultingfamines. Tree- ring s tud ie s in the Southwest have now extended knowledge ondendroclimatology back about 4000 years. During th is period there is ampleevidence of d rought s. Another means of extending the record back to prehistoricclimatic changes is based on the t hic kness o f annual layers of clay arid s i l t

deposited in quiet waters of lakes that are subject to freezing in winter andthawing in summer. In such a study each annual deposit is called a varve.These varves also indicate periods in the past in which droughts have seriouslya ff ec te d th e land.Drought is one of the most devastating aspects of nature. I t is also oneof th e c lima ti c characteristics of the Temperate Zone in which the United States

l i es . As long as the climate is influenced by the circulation of a ir aroundthe earth, there will be c h a n ~ ~ s in the precipitation pattern a t any given spot.Just as certain as there have been droughts in this country in the past, therewill b e droughts in the future. The time of the next drought cannot be exactlyforetold, but i t will obviously follow a period of normal or excess ra infa l l .Who kn:Jws tha t i t may not occu.r next year?

Agricultu.ral losses resulting from the recent drought in Texas, which wasseriously effective between 1950 and 1956, have been estimated by experts tohave exceeded 3 bil l ion dollars. It is probable that in Texas losses in farmingand ra:clching alone have exceeded the aggregate loss due to a l l o ther c lima ti cphenomena including f loods, hur ri cane s and tornadoes, throughout th e y ears.wt,ereas, manifestations of most weather phenomena part icularly the moredestructive type are rather sudden, and the results are rather obvious , droughtsmaterialize so slowly and the i r effects are so long delayed, that the damage isusuall;y- done by the time i t is realized that a drought is being exper ienced .

Of further importance is the fact that the effects of drought ar e u su ally widespread, frequently involving entire sta tes , and sometimes a l l of the UnitedStates. By comparison, a re as a ff ec ted by the other weather phenomena areu s u a l ~ r quite local.


8/81

ACKNOWLEOOEMENTS

Several agencies of the Federal and State governments have made informa-t ion available to be uti l ized in the development of this report . Includedamong these agencies are:

International Boundary" and Water Commission,Department of State

U. S. Weather Bureau, Department of Commerce

U. S . Geo logica l Survey, Department of the In ter ior

U. S. Bureau of R e c l a r r ~ t i o n , Department of theInterior

U. S. Agriculture Stabil ization Committee,Department of Agriculture

Texas Board of Water E:ngineers

Texas Department of Agriculture

Texas Department of Health

Department of Agricultural Economics and Sociology,A &M College of TexasTexas State Library

Bureau of Business ReEiearch, University of Texas

- 2 -


9/81

A S T U D Y OF D R O U G H T SI N T E X A S

INTRODUCTIONThe word drought means many things to many people. Drought i s usuallythought of in connection with agriculture. In terms of agriculture, droughtcan be defined as that deficiency in r a i n f a l l and s o i l moisture over a certaintime which permits the wilting of plants, and which, i f prolonged, can cause acomplete loss of crops. Droughts, according to the above definit ion, can beserious when their duration i s measured in years, months, or even weeks. Suchperiods of deficient r a i n f a l l occur frequently, even in the more humid sectionsof the State. It i s in an effor t to get r e l i e f from this i r regular i ty of rain-

f a l l t ha t ir ri ga tio n works are b u i l t . The application of supplemental waterat the proper time has been found to be a very successful means by which produc-t ion of crops can be assured, with a corresponding increase in income.Cities and municipalities usually associate droughts with deficiencies in

r a i n f a l l and streamflow over longer periods of time. Cities in general a remore prudent than ind iv idual s in providing their cit izens with ample water andmake every effor t t o keep supply in excess of demand. Hence, shortages inwater in the c i t i e s are not generally as frequent or serious as local shortagesin the rural areas.In the minds of those who l ive in the larger population centers, the worddrought does not have the same portent as i t does to the individual in therural area. Deficiencies in r a i n f a l l in c i t i e s do not become real ly significant

u n t i l t he ava il ab le water supp ly i s so depleted that water rationing becomesnecessary. Usually this follows a period of years in which the deficiency inr a i n f a l l accumulates , but during which water i s supplied from carryover stor-age - thoughtfully provided before the drought became evident.

Drought has been defined by Webster as:" . . constitutes dryness;, want of rain or water, especially such drynessby weather or climate as effects the earth and prevents growth of plants."J . C. Hoyt defines i t thus: (See ref . 2.)"Drought conditions may be said to prevail whenever precipitation i sinsufficient to meet the needs of established human a c t i v i t i e s . "These defini t ions are incomplete and do not p rovide a quantitative meansfor measuring drought. General A. W. Greely, the l a s t military chief of the

Federal Weather Service (U. S .. ) , appears to have been the f i r s t to point ou tthe need for a quantitative scale for use in connection with the term drought .He suggested in 1888 that : (See ref . 3.)" . . . . the term be used only for those parts of the country where theaverage precipitation exceeds an inch in each month."

- 3 -


10/81

Gen. Greely also remarked that : (See ref . 4.)" . . . . from an examination of the records i t appears that droughts arevery severe whenever the ra infal l for one or more months is less than 50percent of the average ammlnt, and i t is suggested that the drought unitindicate a deficiency to be determined with reference to the averagemor-thly amount during the time in which the drought prevails ."

H e r ~ (see ref . 5) in 1906 proposed and used a definit ion of drought substant ia l ly as follows:

"Drought: A drought is considered to exist whenever the ra infal lfor a period of 21 days or longer is but 30 percent of the average forthe time and place."Agricultural l i tera ture includes studies ofent defini t ion is usually applied in each case.these agricultural studies appears to be the usean index of agricultural drought.

drought effects , but a differThe common denominator amongof available soi l moistur e as

None of these various definitions is 100,%> applicable to a discussion ofdroughts as related to Texas. ~ r h e lack of a generally applicable defini t ionof drought is noted by Linsley, Kohler, and Paulhus (see re f . 6) as follows:"A sustained period of time without significant ra infa l l is calleda drought. Because of the variety of needs for water, i t is not pract icalto define a drought specifically."

A meteorological basis for the determinat ion of drought has been given byHoyt (see ref . 7) who concludes that in the humid and semi-arid areas droughtconditions exist when there is an annual deficiency in precipitation of 15percent or more. This defini t ion also fa l ls short because i t does no t considerthe time of occurrence of ra infal l . For instance, a def ic iency of less than10 percent of the a=ual ra infal l , i f i t occurs during the growing season, wouldbe much more severe in i t s economic implications than a def ic iency of 25 percentof the annual ra infal l that happened to occur in the non-growing season.

The following d iscuss ion of droughts by Hoyt (see ref . 8) is worthy ofrepeti t ion:"In considering droughts the division of the country into threesections with respect to precipi tat ion - the humid East, the arid West,and the intermediate semi-arid s tates must be kept in mind. In the humidEast precipi tat ion is usually adequate to supply the needs of vegetat ionwithout i r r igat ion, and other activit ies are lim ited by the water suppliesthat can be conserved. The semi-arid states const i tute a section that

ma;}' be ei ther humid or arid, depending on weather conditions in a part icular year."These same divisions are present in Texas - the humid East, the arid West,

and the intermedia te semi-arid part of the State.

- 4 -


11/81

A recent U. S. Weather Bureau publication (see ref . 9) sta tes:"Drought is d if f icu lt to measure objectively. One gauge is i t s impact upon livelihood of the population in the area. This is closelyrelated to the effects of meteorological factors on crops, pastures andwater supply. Because these effects can only be estimated, a somewhatless adequate measuring rod must be employed. The drought is expressedhere in terms of lack of rainfal l as compared to that usually expected."

Palmer (see ref . 10) provides a generalized definit ion of drought bystat ing:"From a meteorological standpoint drought may be considered to be arelatively temporary departure of the climate from the normal or averageclimate toward ar idi ty. This assumes the economy of the region is moreor less in step with the average climate and is , therefore, not seriouslyaffected by the normal u:ps and downs of the weather."

For the determination and comparisons of droughts in this s tudy Hoyt 'sdefinit ion has been used: drought conditions exist when there is an annualdeficiency in precipitat ion of' 15 percent or more.

AVAILABLE DATARecords of rainfal l in Texas generally begin about 1889, although a fewstat ions were started much earl ier; some in th e 1850's. The longest ra infa l lrecord in Texas is that for Austin, which began in 1856 and is continuous withthe exception of a few months in 3 years. Sixty-seven stat ions were in operat ion in Texas in 1891. This number gradual ly increased to 249 stat ions withpublished records in 1940. A l arge incr ea se in the number of ra infa l l stat ionsoccurred after World War I I , w'ith records published for 643 sta tio ns in 1957.These publications of the U. S. Weather Bureau formed the basis for th is study.Information on temperature, evapora tion, and relative humidity for Texas

is generally adequate in coverage, a lthough not as abundant as the ra infa l lrecords. However, since none of these items is as errat ic as rainfal l inoccurrence, the same density of stations as required for ra infa l l is not necessary. Temperature records were obtained from the annual Weather Bureaupublications. Evaporation data were based on publications of the Board ofWater Engineers and the Weather Bureau. Relative humidity data were obtainedfrom monthly U. S. Weather Bureau publications for the period 1940 through1957

Streamflow data used herein were obtained from the Water Supply Papers ofthe U. S . Geologica l Survey and the Water Bulletins of the International Boundary and Water Commission. Records of runoff in Texas generally begin in 1924,although a few records are ava.ilable for ear l ier years. The longest continuousrecord in the State is that for the Rio Grande at El Paso which began in 1889.Other long records include the Brazos River at Waco and the Colorado River atAustin , both of which date back prior to 1900. A gradual increase in thenumber of gaging sta tio ns in Texas took place through the years, with the f i r s tlarge expansion coming in the period 1938 to 1940, when 100 new stations wereplaced in operation.

- 5 -


12/81

Climatologic and hydrologic data for Texas are r ead ily avai lab le . Thesedata have been collected by var ious Federal and State agencies. The si tuat ionwith respect to the assembly and publicat ion of information r el at in g to the impact of weather on the economy of the State is not so complete. Data pertain-ing to floods and flood damage have been collected by the Corps of Engineers.Information on past droughts and drought effects have been collected and pub-l ished by the U. S . Geo logical Survey in connection with studies covering theUnited States. The information that is available is not in detai l for theState of Texas. A deficiency of information exists with respect to the econo-mic impact of past droughts on the State 's economy, although certain generalstudies have been made as to the effects of the 1950-1956 drought.

Data on the effects of droughts a s used in this report have been obtainedfrom publications made available by the Texas State L ib ra ry , th e Bureau ofBusiness Research of the Unive rs ity o f Texas, the Department of AgriculturalEconomics and Sociology of the Agricultural and Mechanical College of Texas,and from the annual reports of the Department of Agriculture, and others.

VARIATION IN ANNUAL RAINFALLPrevious reports (see ref . 11) by the U. S. Geological Survey coveringdroughts in the United States have used average annual ra infa l l for each stateto show the annual variations. Such procedure is adequate for small areas

where there is no great difference in the ra infa l l character ist ics from onepart of the area to the other. Many of the smaller states f i t into this cate-gory. Texas, however, does not lend i t se l f to this treatment. The land areaof Texas is approximately 264,000 square miles, w ith an air l ine distance ofabout 800 miles from Dalhart to Brownsville or from El Paso to Orange. Of moreimportance, however, is the fact that the annual ra infa l l varies from less than10 inches in an average year on the western side of the State to more than 50i nches along the eastern boundary. With the great distances involved and thewide var ia tio n in annual rainfal l , a mean value of ra infa l l for Texas is notonly useless but i t is misleading.

In an effo rt to resolve the difficul t ies imposed by the size of Texas andthe variation in ra infa l l , and yet show the natural fluctuations in annualrainfal::" that do occur, the State has been arbi t rari ly divided into four areas.These areas are of about equal width, which means that there is the minimumvariat ion in ra infa l l over each. They are not of equal area, but for the pur-poses they serve, th e sma lle r variation of ra infa l l in each is of more impor-tance.The four areas into which the State was arbi t rari ly d iv ided a re shown assmall insets , Fig. 1.The average ra infa l l over each of these areas was calculated on th e basisof selected prec ip ita tion s ta tions , a l l of which have ra infa l l records that canbe extended back to about 1889. This average ra infa l l in each case is anarithmetic mean derived without weighting. I t is not indicated, nor is i tassumed) that this average is equivalent to the exact average ra infa l l overeach area. But i t i s assumed that the figures so obtained provide an index

to the ra infa l l over each area, and adequately reflect the relat ive f luctua-t ions in the annual rainfal l , which have occurred in the past . The number ofavailable ra infa l l stations within or adjacent to each area varies, with ato ta l of 46 stations involved.

- 6 -


13/81

WESTERN) ' - - . ~ - - - - - - - - - - - - - -

FIGURE IVARIABILITY IN ANNUAL RAINFALL FOR FOUR AREAS OF TEXAS

- 7 -


14/81

Annual average rainfal l for the 69-year period, 1889 through 1957, foreach of the 4 areas has been plotted on the chart, (Fig. 1) with the westernmost area represented at the top, and success ive areas to the east arrangedin order below. The mean annual rainfal l for each area is shown in the following tabulat ion - in which 85% of the mean is also shown:

AREA OF DIVISIONWesternMid,",[estMid-EastEastern

MEAN ANNUALRAINFALL

11. 74"20.89"30.29"4309"

85% OF MEANANNUAL RAINFALL

998"1776"2575"36.63"Lines r ep re sent ing the se f igures have been shown on the appropr ia techarts. Bars showing annual average rainfal l values for each of the 69 yearsare shown on the charts for the 4 areas. The bars on the diagram for each oft he r espect ive areas are plotted to the same scale. Thus, the contrastinglengths emphasize the variation in annual rainfal l , not only from year to year

over the same area, but also they indicate the relat ive difference in rainfal lbetween d if fe rent par ts of the State.As previously mentioned the upper diagram on the chart shows the year byyear r a : ~ n f a l l for the most westerly sub-division of the State. Mean annualrainfal l for this area was found to be 11.74 inches. The most noticeable thingabout this diagram is the wide range in annual rainfal l . Only once in theperiod cf 69 years were there t'wo successive years having approximately thesame annual rainfal l - that was 1928 and 1929, which both had an annual averageabout equal to the long-time average. Most of the o ther yea rs show the rain

fa l l to be either above or below the long-time average.The ext reme range in annual rainfal l in the Western area is from about

4.2 inches (1910) to 26.7 inches (1941). Within th e period shown, there are28 years in which the rainfal l was above the average; 5 years of approximatelyaverage rainfal l ; and 36 years that were below the average. Of the 36 yearsin which the rainfal l was below average ,J 18 years had less than 85 percent ofthe long-time average .The next chart below shows the annual average rainfal l for the Mid-Westarea, wr.ich in cludes the Panhandle of Texas and the area south to the RioGrande. Average annual rainfal l for th is area is 20.89 inches. Only rarelydoes the annual rainfal l happen to coinc ide with the average, and more rarelydoes i t happen that the same rainfal l is observed for two consecutive years.Once during the 69 years covered by th is study there were two successive years

in w h i c ~ the rainfal l was approximately the same in this area. This was in1933 and 1934, both of which were drought years, with the ra infa l l far belownormal. The extreme variation in annual rainfal l ranges from about 9 inches(1956) to 34.4 inches (1941). Within the 69-year period shown, there are 31years i which the annual rainfal l was above average; 4 years of approximatelyaverage rainfal l ; and 34 years in which the annual rainfal l was below theaverage. Out of the 34 years which had below the average, 21 years had rainf a l l less than 85 percent of the mean annual rainfal l .

The next chart , representing the Mid-East area, includes what i s generally referred to as central Texas. Average annual rainfal l for this area,

- 8 -


15/81

based on the 69-year r ~ c o r d , was found to be 30.29 inches. Only two years hada p p r o x : ~ m a t e l y this average rainfal l . All of the remainder fluctuated widelyeither above or below this mean ra infa l l . There were 32 years in which theannual rainfal l was above, the average, and 35 years with less than the averagerainfal l . There were 15 yearf:, out of the 35 low years in which the annualrainfal l was less than 85 percent of the long-time average. The extreme rangein the variation of annual rainfal l for this area was from 15.9 inches (1917)to 50 inches (1919).

The lower chart r ep resent s the Eastern area, where the long-time averageannual rainfal l is 43.09 inches. No single year had this exact rainfal l .There were 29 years in which the annual rainfal l was above the long-time average, while the remaining 40 y ~ a r s had below average rainfal l . Three of theseyears had a rainfal l of approximately 85 percent of the average. Out of theremaining years that were belcM average there were 14 years in which the annualrainfal l was less than 85 pereent of the average. The extreme range in thevar ia tio n in annual ra infa l l was from 27 inches (1917) to 62 inches (1946).

These figures have been summarized in Table 1.

EXTENT AND SEVERITY OF DROUGHTSDETERMINATION OF DROUGHT PERIODS

The time of occurrence, extent and severity of a number of droughts hasbeen determined for the State in relation to the rainfal l records. The preliminary finding of occurrence of droughts was determined by the preparationof mass curves of accumulated annual rainfal l at 46 stations with long-timerainfal l records covering the period 1889-1957. Forty of these were Texasstations with the remaining six in adjacent states. These stations are l is tedin Table 2. Periods of rainfal l deficiency as indicated by the slope of themass curves were then studied in detai l .

As previously shown the definitions of droughts vary with the type ofwater use, the place, and the len gth of time covered by the drought. Hoyt(see ref . 7) used departures f ~ o m the mean annual rainfal l as the cri ter ia fordetermining drought. Henry (see ref . 12) also indicated that the annual rainfa l l was adequate for the purpose, as per the fol lowing quote:

"The facts hereinbefore presented lead to the belief that in thegreat majority of cases the to ta l annual precipitation may be used as acri ter ion on drought."Rainfall has been shown to vary for the different areas of the State, andwi th respect to time at the same location. R ain fa ll is erratic in point oftime whether the unit of studJ" is day, week, month or year. Each precipitatio n s ta tio n measures the rainfal l at a given point. Since rainfal l is quiteerratic in reference to area i t is evident that some points may have receivedmore rain and some less than the amounts specifically measured in the samegeneral area. However, the past measurements can be uti l ized as indices ofthe rainfal l for the general area in which the station was located. The calendar year has been used hereln as the unit of time for rainfal l data.

- 9 -


16/81

TABLE 1RAINFAIJ, VARIATION OVER TEXAS

Areas of the StateWestern Mid-West Mid-East Eastern

Average Rain fall in Inches Period1889-1957 11.7 209 303 43.185 Percent of Average Rainfall 10.0 178 25.8 36.6

Minimum Annual Rainfall 4.2 90 159 270Year of Minimum 1910 1956 1917 1917Maximum Annual Rainfall 26.7 34.4 50.0 62.0Year of Maximum 1941 1941 1919 1946

Number of Years with Rainfallabove Average 28 31 32 29Number of Years with Average Rainfall 5 4 2 0

Number of Years with Rainfallbelow Average 36 34 35 40

Number of Years with Rainfall85 Percent of Average or Less 18 21 15 17

- 10 -


17/81

Average RainfallAs a base from which to measure deficiencies in ra infa l l (and that is whata drought i s ) , i t was necessary to select a period of ra infa l l that was commonto a sufficiently large number of s ta tio ns t o be representative o f condit ionsover the State. Fortunately, through previous study, i t was known that theperiod. from 1924-1956 (33 years) was r ep re sent at ive of a much longer time interval , as shown by the comparative figures in Table 2. Also, i t was knownthat about 300 rainfall stations in the State (or immediately surrounding i t )

had records that were continuous for the period, or that cou1.d be extended tocover the period by correlation. This period was, therefore, adopted as thestandard time interval for which a l l departures from the average cou ld bemeasured.A map of the State was prepared to show th is 33-year average ra infa l l fora l l of these sta t ions. Lines of equal ra infa l l (isohyetals) were then interpolated between the points.Use was made of many additional stations for individual drought periods,depending upon the span of years "for which the records were available. Thesestations were properly loca ted on the map and the average ra infa l l was deter

mined from the l ines of equal rainfall . Al l def ic ienci es have been measuredfrom the common base, as a b o v l ~ described.Rainfall Deficiencies

For a l l of the early droughts the annual rainfall was l is ted for eachstat icn. As the number of stations increased greatly af ter 1947, only about300 selected stations were used for the droughts after that time. The ra infa l lwas taoulated for the fu l l period of low rainfall , plus a year preceding andone year fol lowing. The annual departure from the long-time average ra infa l lfor each stat ion was then calculated. With these departures calculated, i twas t hen possibl e to place the l imits on the drought as to beginning and ending.The years of drought were not always the same for a ll stat ions. I t f requently happened that the drought started earl ier in one part of th e State thani t did in another part - and the end of the drought was a lso q uite v ar ia ble .Thus, there were oft en ind iv idua l ra infa l l stations which had deficiencies in

ra infa l l in years ei ther before or after the so-called drought. Only thoseyears were included in the drought period in which the greatest number of stat ions showed deficiencies.After the years to be included in the drought were determined, the annualdepartures from the mean were accumulated for each station' and i sohyet al char tswere plotted showing the accumulated negative departures in inches. Theseaccumulated deficiencies were then converted to an average annual deficiencyas a percentage of the mean annual ra infa l l . These percentages were plottedon the small inset maps of eaeh chart. The areas included with in t he 15 percent dashed l ines on the inset maps were considered to be in droughts. Areaswith the higher percentage deficiencies were generally those which had experienced the more severe drought e"ffects.

Descriptions of Historical DrOUghtsA descript ion of each of the droughts which has occurred since 1889 hasbeen prepared, together with a chart showing the extent of each drought.

- 11 -


18/81

TABIE 2COMPARISON OF AVERAGE RAINFALL FORTWO PERIODS AT CONTROL STATIONS

Units: InchesAverage Rainfall Average Rainfall1889- 1924- 1889- 1924-

Station 1956 1956 Station 1956 1956Abilene 23.61 22.85 Hallet t svi l le 34.86 34.67Albany 2523 24.80 Haskell 2319 2337Amarillo 20.28 19.34 Houston 44.70 4308Arthur City 3995 40.40 Huntsville 44.73 45.02Austin 3303 31.90 Lampasas 2902 28.92Beaumont 52.03 52.42 Llano 24.91 26.62Boerne 31.95 30.52 Longview 4398 4338Brenham 39.44 3830 Luling 31.85 32.11Brownsville 2497 26.86 New Braunfels 30.47 30.81Brownwood 26.49 26.20 Palestine 3926 38.66College Sta. 37.94 3790 Paris 40.60 42.81Corpus Christi 2558 26.80 Plainview 2034 1907Corsicana 36.04 35.89 San Antonio 2639 26.24Crosbyton 20.82 20.80 Temple 33.89 33.18Cuero 3390 3236 Waco 33 53 31.15Dallas 34.14 3270 Weatherford 31.15 30.69Eagle Pass 20.07 1951El Paso 8.18 7.66 In Adjacent StatesFairland 28.13 27.60 Mena, Ark. 5271 5279Fort Clark 20.85 1983 Texarkana, Ark. 46.29 48.72Fort McIntosh 18.83 1830 Shreveport, La. 42.54 44.37Fort Worth 31.56 30.63 Lk. Charles, La. 56.15 54.81Gainesville 3505 3387 Ag. College, N. M. 8.19 8.03Galveston 42.80 4338 Carlsbad, N. M. 1321 11.61

- 12 -


19/81

The duration of these droughts varied from one to four years w ith theexception of the most recent drought which lasted from 1950 through 1956 insome Tarts of the State. Droughts of less than one year have not been considered in this study. Other single years of recorded rainfal l not included asd r o u g h ~ ~ s , had local rainfal l deficiencies of 15 percent or more. However,each of these occurred between years of average or greater than average rainfal l , and none had ei ther the areal coverage or severi ty to just i fy classingthem 8B individual droughts.

Drough:; of 1891 - 1893Isolated drought conditions prevailed over parts of the State duringthese three years. While only abou t 65 rainfal l records were available atthis date, they indicate accumulated deficiencies of rainfal l in excess of40 inches in the Beaumont area and more than 30 inches at Luling. The rain

fa l l deficiencies in inches and the average annual deficiencies as percentagesof the mean annual rainfal l for this drought are shown on P late I .'Iva general drought ar ea s w ith deficiencies of more than 15 percent ofthe mean annual rainfal l , as shown by the small inset map, involved narrow

a reas general ly along l ines between Del Rio and Fort Worth and between Lulingand Richmond. Further small drought areas also occurred with widely scatteredcenters in Harley, Culberson, and Dickens Counties.While small rainfal l deficiencies extended over much of the State, onlythese relat ively small areas were se rious ly af fec ted . This drought followedseveral years in which the ra:lnfall had been above average. I t is probablethat the ground water had not been seriously depleted. It is noteworthy thatmost of the affected area was in the sem i-arid reg ion of the State with onlya small portion of the humid area being affected.

Drought of 1896 - 1899Although records of rainfal l for this period are few, they show th is tobe one of the most severe droughts, in terms o f def ic iency in inches, that hasbeen experienced since 1889. Three widely separated centers show an accumulat ive deficiency of greater than 50 inches in the four years. Two of them showa def ic iency o f more than 60 inches. Of these t hr ee cen te rs two are near thecoast , while the other is far inland. The two which are near the coast are atopposite ends of the Texas Coastline - one near Brownsville; the other nearBeaumont. Paris , near the Red River in northeast Texas, is the locat ion ofthe thi rd center. These separate cen ters are shown on Plate II .The two main surrounding areas that show evidence of the drought areseparated, with above normal rainfal l in between. The area of greatest deficiency was along the eastern border of the State, and near the coast, wherea total def ic iency o f more than 90 inches is indicated. I t undoubtedly isassociated with the center in northeast Texas, although a part of the areabetween the two centers was only sl ightly affected by the drought.T:'le center of high deficiency near Brownsville spread northward along thecoast , and then extended inland to south-central Texas, with most of this partof the area hav ing only a small deficiency.

- 13 -


20/81

As shown by the small inset map, there are two centers in which theaverage annua l deficiency was above 40 percent, with th e h ig he st percentagebeing in the southern t ip of Texas, where the maximum deficiency was in excessof 60 percent of the mean annual ra infa l l . In spi te of the fact that the accumulative deficiency in inches was greater in southeast Texas, the percentagedeficiency was much less than near Brownsville, because of the higher meanannual ra infa l l in the Beaumont area.In terms of the percentage of the mean, and according to the definit ion

which l imits drought to those areas with deficiencies in annual ra infa l l greater than 15 percent, th is drought was fair ly well limited to south and eastTexas, with a few isolated centers scattered elsewhere in the State.More than three-fourths of the State, including most of central Texas anda l l of west Texas, seemed to have escaped th is drought.

Drought of 1901This is the only drought tha t has been considered in th is study whichconsists of a single year (unt i l 1953, which was part of a 3 drought series) .The reason for i t s inclusion is tha t i t followed the 4-year drought of 1896through 1899 by only one year. Even though i t is classed herein as a separatedrought, i t is quite probable tha t the effects of the previous drought hadnot been overcome, and i t might more appropriately be handled as a continua

t ion of that ear l ie r drought. In fact , there were only two years of more orless average ra infa l l over most of the State in the interval between the 18961899 drought and the s t i l l ear l ie r one of 1891-1893. I t is doubtful whetherfu l l recovery of the depleted ground-water storage as a resu l t of the f i r s tdrought had t aken p lace by the time the second drought started. There waspractical ly no sur face s to rage in existence a t the time. The accumulativedeficiency in inches i s shown on Plate I I I .

Examination of the three charts (Plates I , I I , & I I I ) shows th at c erta inareas of the S tate were adversely affected by a l l three of these droughts.These areas are along the coast, with the southern t ip of Texas and the coastalarea of east Texas both being in the drought area for a l l three periods. Thus,these areas were in drought for eight years out of the eleven during theperiod 1891-1901. Possibly, the recent drought, which extended generally from1950 through 1956, was not the longest drought of record.

This early drought had the grea te r de fi ci enc ies in to ta l ra infa l l throughcentral Texas and the southern part of east Texas. A larger area in. northeast Texas was exempt from the drought effects , as well as pract ical ly a l l ofthe western half of the State.With the deficiencies shown in terms of the percentage of the mean annualrainfa:_l, on the small inset map, i t may be seen that over half of the Statewas within the l imits of 15 percent. The greatest percentage drought was alongthe Rio Grande, where the deficiency in th is single year was more than 70 percent . A large area along the Rio Grande and extending almost continuously tothe Red River th rough central 'Texas had a deficiency of more than 40 percent.

- 14 -


21/81

Drought of 1909-1912~ h heart of Texas and well into east Texas was more widely affected bythis drought than i t had been by most of the others. This drought was morewide-spread. Numerous isolated centers had accumulative deficiencies in rainfa l l in excess of 40 inches for the four years, and two areas in northeastTexas had def ic ienc ie s in excess of 60 inches.A s t r ip along the border in east Texas, and a l l along the coast , plus

most of the Panhandle and far west Texas apparently missed th is drought buta l l of the remainder of the State showed these r a in f a ll de fi c it s.The a reas a ff ec ted by this drought are shown on Plate IV.In terms of percentage of the mean about three-quarters of the State waswithin the area of drought with respect to the definition which includes a l lareas with deficiencies in annual ra infa l l in excess of 15 percent. While thedrought was wide-spread the percentage deficiency exceeded 20 percent in onlyabout one-fourth of the area of the State. Areas in which the deficiencieswere greater than 30 percent were r ath e r limi ted, with the largest such areabeing north and east of Dallas.Of the early droughts for which there are available records th is was themost prominent drought that had been experienced in north-central and northeast Texas.Law ra infa l l caused lower runoff, and consequently water shortages wereexperienced by many of the ci t ies in central Texas. Incident to the watershortages there were serious f i res in a t least three of the larger ci t ies inTexas: Dallas, Houston and Fort Worth.

Drought of 1916-1918Most of Texas was adversely affected by this drought as shown on Plate V,with only the extreme western part and the Panhandle being excepted. Thegreatest deficiencies of rainfal l were along the coast and the southern partof east Texas, where a larg e area indicated deficiencies in excess of 30 inchesfor t he t hr ee -yea r period. Several smaller and isolated areas had deficienciesgreater than 40 inches during this time.In the midst of this wide area that was accumulating deficiencies inra infa l l , there were three widely separated areas which had nearly normal rainfa l l . One of these areas was along the Rio Grande in Starr and Hidalgo Count i es . Another extended westerly from San Antonio through Uvalde County. And

the third was an area surrounding Dallas and Fort Worth and extending northwardto the Red River.The small inset map indicates that practically the entire State wasaffected by the drought to a certain extent. Four small areas - a l l far apart,show deficiencies greater than 40 percent of the mean annual ra infa l l . Two ofthese are in south Texas, while the other two are in west Texas. The percentagedeficiency was generally greater in west Texas than i t was in east Texas, because of the lower mean annual. ra infa l l in west Texas .Based upon a drought determination defined by deficiencies which equal orexceed 15% of the annual rainfal l , practically the entire State was in a

- 15 -


22/81

drought at this time. Except for extreme west Texas, only two areas wereexempt from the effects of th is drought. These were the area west from SanAntonio, and the other from Dallas and Fort Worth northward to the border ofthe State.In the succession of droughts across Texas as indicated by the early rain

fa l l records, this was the most severe in i ts impact on the economy of theState that had been noted to that time. This was probably not entirely due tothe physical shortage in ra infa l l , which was wide-sp read , but due more to thegreater population and the increased development that had taken place in Texassince the ear l ie r droughts.

Drought of 1924-1925This drought, which lasted only two yea rs, a ff ec ted most of th e e as te rntw o-thirds of the State. Accumulative ra infa l l deficiencies of over 40 inchesoccurred along the eastern border in Sabine County with defici ts of over 30inches occurring in six more counties in that general area.Another small area with greater than 30 inches of def ic iency was locatedin the northeastern corner of the State and included parts of four counties.Rainfall deficiencies for the drought are shown on Plate VI.Deficiencies in excess of 30 percent of the mean annual ra infa l l as shownon the small inset map were located along the mid-section of the eastern border, along the Red River from Bowie County to Clay County, and in three smallareas centered in Blanco, Coryell, and Gonzales Counties. Areas with defic ienc ie s o f less than 15 percent, or with no deficiency at al l , included theHigh Plains , extreme wes t Texas, the Lower Rio Grande Valley, and the centralGulf Coast. The aggregate of these areas amounted to about one-third of theState.

Drought of 1933 - 1934Notable deficiencies in ra infa l l during th is drought were general acrossa wide area extending southwest from th e nort he as t corner of the State nearTexarke.na to the Rio Grande. There was then a bend across the northwesternpart of the State in which the deficiencies were not so great. North of th isband of small deficiencies, the Panhandle was more seriously affected by thedrought. An area a l l along the coast, and extending inland approximately 200miles from the coast, suffered only s l ight deficiencies in ra infa l l . Most ofthe southern half of th is area actually had more than the mean annual ra infa l land an average for the two years. The distribution of this drought i s shownon Plate VII.While the depth of the deficiencies in inches was not great over a greatpart of west Texas, the drought was much more severe in this section than incentral Texas as revealed by the small inset map, which shows the averageannual deficiency in terms of percentage of the mean annual rainfal l . All ofthe western half of the State showed a deficiency greater than 15 percent ofthe meaa annual ra infa l l except two small areas in the Panhandle. Most of thisarea had a deficiency in excess of 30 percent for the two years, with the maximum deficiency in southwest Texas being greater than 60 percent.

- 16 -


23/81

This particular drought in Texas represents the eastern extension of oneof the most severe droughts ever experienced on the southern Great Plains .The upper area in the Panhandle was included in what was popularly called the"Dust Bowl".D etails of this drought have been documented by Hoyt with the resul tspublished in Water Supply Paper No. 680 - "Droughts of 1930-34".

Drought of 1937-1939This drought affected two dist inct areas entirely apart from each other,and separated by a zone from east to west across the c en tr al p ar t of the State.The nor thern a rea extended from the Louis iana border northwesterly to the RedRiver across north-central Texas. The southern area included the entire coast

a l area and extends west to intersect the Rio Grande a l l the way from Laredo toDel Rio. The greatest deficiency in inches was along the eastern border of theState near the coast , where the three-year cumulative deficiency was more than40 inches. Aside from this small a re a th ere were several isolated centers insouth Texas and along the coast in which the to ta l def ic iency with in the droughtperiod was greater than 20 inches. In the northern drought area th er e was onlyone s m ~ l l area in which the accumulated deficiency was more than 20 inches.The areas affected by this drought are shown by Plate VIII.

1'2 percentage of the mean a=ua l ra in fa ll most of south Texas came withinthe limits of the 15 percent def ic iency which defines a drought. One smallarea had a deficiency in excess of 30 percent. A relat ively small area innorth Texas fe l l in this category, with no high percentage deficiencies.

Drought of 1950-1952A " ~ o u t half of the State was adversely affected by this drought, withaccumulative deficiencies in rainfal l of more than 10 inches. Even though itwas wide-spread, the deficiency in rainfal l for the three years was not greatexcept in a few isolated spots. Most of north Texas, the Panhandle, and west

Texas were free from i t s effects, with many spots in centra l and east Texasalso exempt. Three widely se:parated areas had a to ta l deficiency of more than30 inches. These areas are shown on Plate IX.The small inset map, upon which the drought is shown as the average annual deficiency in rainfal l in terms of percentage of the long-time average

rainfal l , shows a l l of the southern part of the State and most of centra lTexas included in the limits of 15 percent deficiency.One thing that made this drought so greatly noticed was that i t followeda 10-year period during which rainfal l in general was high w ith both 1941 and1946 having rainfal l much in excess of n o ~ l .

Drought of 1953This year has been handled separately because i t is not l ike the droughtyears which immediately preceded i t , nor is i t similar to those three yearswhich followed directly after i t . In eastern Texas, along th e coast, and

- 17 -


24/81

several str ips in northern Texas there was no drought during the year. Actual ly , ra infal l was in excess of the average in the above areas. Most ofcentral Texas and a l l of west and southwest Texas, however, had deficienciesin ra infal l . This dis tr ibut' ion of the drought and non-drought i s shown onPlate X. The result of this d is tr ibut ion in ra infal l was that part of theState continued in drought whi le another part got some re l ief from the deficiencies which had prevailed throughout the preceding three years.

Drought of 1954 to 1956Most of the droughts that have been experienced in Texas since ra infal lrecords became available have been preceded by one or more years of aboveaverage rainfal l . This drought is an exception, however. In more than onehalf of the State, drought conditions had prevailed throughout the precedingfour years. Only parts of the eastern half of the State were afforded a cer

tain amount of re l ief in 1953.The drought which started with 1954 proved to be one of the most widespread, as well as one of the most severe that has ever been experienced in

the State . All sections experienced deficiencies in rainfal l , but these deficiencies were much less along the Rio Grande and in west Texas than elsewhere.Considerably more than one-half of the State, including a l l of central andeast Texas, had accumulated deficiencies in excess of 20 inches for the threeyear period. About half of this area had to ta l deficiencies in excess of 30inches, and a small area extending far inland from th e coast had a to ta l threeyear def ic i t of more than 40 inches. The areas affected by this drOUght areshown on Plate XI.The small inset map shows that only five rather minor areas scatteredacross the northern part of Texas, variously located from the Louisiana borderto New Mexico, had average annual deficiencies in ra infal l that were less than15 percent. I t is probable that the aggregate of these areas was less thanfive percent of the to ta l area of the State. With t he def ic iency shown interms of percentage of the long-time average annual ra infal l , i t can be notedthat more t han one-hal f of the State , including most of the southwest part ,plus the upper part of the Panhandle, had an average annual def ic i t of morethan 30 percent, and a large part of this area was short by more than 40 percent of the average annual ra infal l .For the western part of the State where the drought was continuous forseven years, th is was the longest drought that has been experienced in Texas.The nearest approach to such a s it ua tion i n some parts of the State was from

1891 to 1901, an l l -year period in which 8 years out of the 11 were droughtyears. Since none of the three non-drought years provided much excess rainfa l l , there was probably a ful l eleven-year period at that time during whichcarryoyer storage would have been required. Lack of development then precluded the disastrous results which are associated with the more recent drought.Summar;>' of the Eleven Droughts Since 1889

Not a l l of the droughts which have been experienced in Texas have affected the same area. As a means of comparison, the area that was enclosed by thel ine representing an annual rainfal l deficiency of 30 percent of the long-timeaverage during each drought has been used. These areas each appear on thesmall inset map, with a l l droughts represented, except the year 1953, which

- 18 -


25/81

was not shown in that form. For convenience, the different droughts have beenplaced into three groups.The areas affected by the early droughts were generally spotted, as

measured by the 30 percent l ines . The drought of 1891-1893 shows only threesmall areas that were so affected. These are a l l in the southern or southwestern part of the State. The drought of 1896-1899 did not overlap any ofthese areas of the earl ier drought, but affected two areas at opposite ends ofthe Texas Coast, plus two more sma ll er a reas along the Red River. These f i r s ttwo droughts were of three and four years ' duration respectively. The thirddrought in 1901 was for a s ingle year. The deficiency in rainfall in that oneyear was wide-spread, enveloping about half of the southern part of the State,plus a much smaller area in north-central Texas. Most of the western, northwestern, and northeastern portions of the State were not se rious ly a ffec ted byany of the three droughts.

The droughts which occurred in the mid-part of the record also varied asto location. The drought of 1909-1912 shows three small areas in which theaverage annual deficiency in rainfall was greater than 30 percent of the meanannual rainfal l . The drought of 1916-1918 was much more wide-spread. Thelargest a rea a ff ec ted was in the southern half of the Mid-West area. Numeroussmaller a reas in south and east Texas were affected, but in no case did theseareas overlap the areas which suffered most in the previous drought. The nextdrought, which took place in 1924-1925, had a number of scattered centers inwhich the rainfall deficiency exceeded 30 percent of the long-time mean annualrainfall . All of these were in the eastern half of the State, and they wereso distributed that they missed the location of the two previous droughtsexcept for one small overlap in north Texas. The drought of 1933-1934 had alarge area w ithin the l imits of the 30 percent l ine, but i t was confinedwholly to the western half of the State. I t overlapped for the most part thelarge area that was affected by the earl ier drought in 1916-1918. This droughtwas the extension into Texas of a much larger drought centered around the "DustBowl", which is made up of parts of f iv e S ta te s: Texas, Oklahoma, New Mexico,Colorado and Kansas. After a lapse of two yea rs ano ther drought was in progress within the State during 1937 to 1939. However, i t was not as severe asmost of the others, and only one small area in south Texas had a rainfall d e f ~ciency as high as 30 percent.

The recent droughts, (or the one continuous drought) since 1950, have beenmore serious than previous droughts, not only because of their severi ty, bu talso because of the large area affected. During the early par t of the drought(1950-1952) the areas of greatest percentage deficiency in ra infa l l were thesouthern and western parts of the State, with the largest concentration of thedrought effe cts in what is generally known as southwest Texas. This was followed by a single year (1953) in which some re l ie f was afforded from the d r o u g h ~in east Texas where i t had not been too severe previously. All of west Texascontinued to be influenced by drought. Starting with 1954 one of the mostsevere droughts ever experienced in Texas was under way. I t generally increasedin severity with each year thrOUgh 1956. In that time i t had spread to includemore than half of the State within th e l imits of the 30 percent deficiency line"West Texas was the most ser ious ly hur t by th is drought because i t was continuously under drought conditions for more than seven years. In some parts ofthe western are a, th ere was complaint of drought even prior to 1950.

- 19 -


26/81

Further detai ls concerning these droughts have been brought together forcomparison in Table 3, with the same four divisions of the State used as before.Severity of Droughts

The analysis of rainfal l deficiencies during drought periods just described with the results given in Table 3 shows the deficiencies in terms ofinches and t e l l s when the most serious annual deficiencies occurred. Thatanalysis divides th e State into four sections and shows average rainfal l deficiencies in each section. Data on rainfal l deficiencies in terms of percentage of the mean annual rainfal l for each of the four sections are given inTable L,.

The greatest deficiency as a percentage of the mean annual rainfal l wastaken as the indicator of the most severe drought in each area. This wasfollowed by the second largest percentage deficiency being rated the secondmost severe drought, and the method extended through the eleven droughts.This order of severi ty is l is ted for each area in Table 5. The severity of thedroughts on a state-wide basis was determined by assigning a weight of 11 tothe most severe drought in each area, a weight of 10 to the second most severe,and continuing to a weight of 1 for the leaSt severe drought in any area. Theaccumulated weighted values for the four sections were then obtained for eachdrought. These values indicated the droughts to be in the following order ofseveri ty on a state-wide basis.Most Severe 1954-56 Seventh 1950-52Second 1916-18 Eighth 1924-25Third 1909-12 Ninth 1891-93Fourth 1901 Tenth 1937-39Fifth 1953 Eleoventh 1896-99Sixth 1933-34Since the 1954-56 period is the most severe, and since i t is immediatelypreceded by the f i f th and seventh ranked droughts, and since i t is a continuing series of years of deficiencies without break, i t i s indicated tha t thisseries comprises the most severe seven-year drought period that the State asa whole has experienced with in th e period of some 70 years for which rainfal lrecords are available.

TEMPORARY SHIFTS IN CLIMATE DURING DROUGHTSTexas borders on a desert area, and a part of the State l ies in the arid

region of the Great Southwest. The State has deser t c lima ti c characteristicson one side, with humid conditions prevailing on the other. There is an intermediate zone between the two that i s neither arid nor humid. This intermediatearea constan tly changes and shifts in location over an appreciable distancefrom year to year as the rainfal l varies.

In years of more than average rainfal l , the humid area expands and movesfar to the west. Agriculture under such conditions proves to be profitablewithout i r r igation over a huge area.

- 20 -


27/81

TABLE 3MAJOR DROUGHTS IN TEXASTHEIR DURATION AND EXTENTQ

Q)'H Q)o Q ' H ..-i ( IQ o


28/81

TABLE 4COMPARISON OF RAINFALL IN DROUGHT YEARS WITH THE

LONG-TThlE AVERAGE RAINFALLUnits: Inches

Western Mid-West Mid-East11.74 20.89 30.29Drought Total Ave. Ann. Total Ave. Ann. Total Ave. AnNo. Years Dept. %Def. Dept. %Def. Dept. %De

1 1891- - 6.76 192% - 992 15.8% -1271 14.018932 1896- -232 4.9% + 2.84 0 -10.29 8.518993 1901 - 0.08 07% - 4.15 19.9'/0 -11.00 36.44 1909- -12.84 27.3% -1721 20.6% -25.68 21.21912

16.3'% 32.0%~ 1916- - 575 -20.02 -18.59 20.519186 1924- + 0.23 0 - 355 8.5'% -11.83 19.519257 1933- - 8.47 36.1'% -12.78 30.6% - 8.47 14.019348 1937- - 3.82 10.8,% - 5.61 9.0% -11.83 13.019399 1950- - 3.60 10.2,% -1347 21.5% -14.41 15.9

195210 1953 - 572 48.8% - 6.83 32.7% -. I. .... 11.3j. '+j11 1954- -11.02 31.3% -1935 30.9% -3300 36.31956

Wtd. Mean% 17.7% 18.7% 16.4%


29/81

TABLE 5ORDER OF SEVEmITY OF DROUGHTS AS INDICATED

BY DEFICIENCIES OF RAINFALL IN PERCENTAGE OF THEM E ANNUAL RAINFALL

Order of Severity Western Mid-West Mid-East Eastern1 (most severe) 1953 1953 1901 1954-562 1933-34 1916-18 1954-56 1916-183 1 9 5 4 - ~ > 6 1954-56 1909-12 19014 1909-J2 1933-34 1916-18 1924-255 1891-93 1950-52 1924-25 1909-126 1916-18 1909-12 1950-52 1896-997 1937-39 1901 1933-34 1950-528 1950-5;2 1891-93 1891-93 1937-399 1896-99 1937-39 1937-39 1891-93

10 1901 1924-25 1953 1933-3411 1 9 2 4 - ~ ~ 5 1896-99 1896-99 1953

- 23 -


30/81

All uses of water increase at these times. F a r m ~ n g receives the greatestbenefit in increased yields, which place agriculture on a high economic level,with prosperity widespread. This higher economic level in agriculture takesalong with a general improvement in the f inancial structure throughout thearea.Scarcity of ra infa l l becomes a thing of the past, Shortages of water,which resulted in hauling water for necessit ies in some communities, andcaused rationing of the supply in many others, are a l l forgotten. Water supplyfor the ci t ies creates no problem. Industrial supplies are ample, the reservoirs are ful l , and th e fu tu re looks encouraging.In years of drought just the opposite takes place. The l ine of sufficient

ra infa l l to produce crops shif ts far to the east, and the area that is capableof making a profi t in agriculture shrinks materially.As a resul t of the deficient rainfal l , agricultural yields , and businessactivi ty in the area reaches a low ebb. Water in storage, providentiallycaptured during ear l ier years of ample ra infa l l , is rapidly depleted, byreduced runoff, by increased demands incident to this drought, greater evapora

t ion losses, due to higher temperatures, along with o ther c limat ic factors, a l lof which combine to reduce the water supply. All of these evidences of droughtare visible, but they never seem to make a lasting impression on the public.On the basis of this shift ing climate, there are three dist inct agricultu ra l areas in Texas, which may be described as fo llows:A. The west, where ra infa l l is universally inadequate for dry farming,although in exceptional wet years such as 1941 there may be enough

ra infal l to produce certain grain crops.B. The east , where there is always enough rainfall to produce a crop,

even though the monthly distribution is such that agriculture wil loccasionally suffer.C. The intermediate zone, which l ies between the above two. I t is made

up of a st r ip through the heart of Texas extending from the Rio Grandeto the northern boundary, which is some 200 to 300 miles in width, andconstantly changing in location. I t is man's attempt at agriculturein this shift ing zone which magnifies the i l l effects of drought.TLe intervals between past droughts t e l l a worthwhile story. Between theend of the f i r s t drought for which records are available in 1893 to the beginning of' the worst drought on record in 1950, the lengths in years for therespective drought-free periods were as follows:

2,1,7,3,5,7,2 and 10.The shortest was a l-year interval, while the longest was 10 years. Thismeans that the time in which there will be ample rainfall is limited betweendroughts to probably about five years on the average. The time to build upreserves is these years in which there is surplus ra infa l l . In the la teryears in which drought envelopes the land, there is not enough water suppl iedby rai : l fal l to meet the ordinary requirements, and no opportunity ex ists tobuild -.lp reserves of any kind.

- 24 -


31/81

I is in the intermediate semi-arid zone that disaster so often s tr ikes .The difference in location of the outside l imits of this zone between a yearof ample ra infa l l and the low rainfal l characterist ic of a drought year, hasbeen feund to be about 200 miles. This sh i f t is ei ther east or west, dependingupon t te climatic conditions. The area involved is made up of a str ip about200 miles wide, east and west, by about 500 miles north and south, which wouldincludE approximately 100,000 square miles. I t can be safely concluded thatthese ~ ~ r i o d i c shif ts in climate frequently involve more than one-thi rd of thearea of the State, and in cases of severe drought, can seriously affect up toone-half of the to ta l area of the State.

D"ought periods are general ly characterized by certain climatic phenomena, which may be briefly described as:Less than average ra infa l lAbove average temperaturesGreatly increased evapora tion ratesLow relative humidity

All of t he se c lima ti c factors combine in times of drought against agriculture.Taken individually, the effects would not be so disastrous, but even so, theresul ts could be noted. Figures are ava il ab le for each of the above factorsfor maLy stations scattered throughout the State, which show how they act intime of drought as compared with times of ample rainfal l .

AL examination of the rainfal l records during the drought periods, and acomparison of them with the long-time average ra infa l l has been made for eachof the 11 drought periods. The draught periods were analyzed on the basis ofthe average annual ra infa l l for the four areas of the State, with the resul tsas shown in Table 4. The to ta l deficiency, determined as the cumulativedeparture from the long-time mean for the period covered by each drought, wasfound to vary with respect to the different areas of the State as follows:Total Deficiency Wtd. Meanin Inches %DepartureFrom To

Western 0 12.84 177Mid-West 0 20.02 18.7Mid-East 3.43 3300 18.4Eastern 0 31.34 137I t can be seen from Table 4 that a l l parts of the State were not similarlyaffected by the different droughts. The droughts which were the most severe in

one part of the State were f requen tly o f minor severity in other areas. Theonly drought with any degree of severity in a l l sections was No. 11 , the period1954-1956, which was third most severe in the western half of Texas, but whichranked second and f i r s t in severity toward the east .

Temperature records a re ava il ab le for a large number of Weather Bureaustat ions back to 1924. The records of mean annual temperature were examinedfor 24 selected stat ions scattered throughout the State. The long-time averageannual temperature was determined for each of these for the period 1924-1957.The average temperature was then determined for the 14 drOUght years that haveoccurred since 1924. The results are shown in Table 6 in paral le l columns.

- 25 -


32/81


33/81

The d:':.fference between the long-time average temperature and the averagetemperature during the drought years is 0.8 degrees . At f i r s t glance, i twould seem that this difference is rather small. But when i t is consideredthat this difference applies to each day in the year, i t is not so small aftera l l , amounting to approximately 300 day-degrees. The effects of temperatureon water supplies during drought is aptly stated in the Old Testament (Job24: 19), "Drought and heat consume the snow waters."

Data on evaporation rates, published by the Board of Water Engineers (seeref . 2-3) reveal substantial increases in evaporation rates during periods ofdrought. With the State divided into four areas as shown in this report , thedifference in the annual gross evaporation was determined for each area:

ANNUAL GROSS EVAPORATION

WesternMid-WestMid-EastEastern

Ave. 194o-:2l90.179.872.0503

Ave. 150-' 5695.887778.0555

PercentageIncrease6.310.08.410.1

A weighted mean for the State shows the annual gross evaporation to benine percent greater during the seven drought years 1950-1956 than i t was forthe fu l l period since 1940.Net evaporation losses are obtained by sub trac ting the effective ra infa l lfrom the gross evaporation figures. Since ra infa l l is deficient during droughts,the amount of ra infa l l available to offset gross evaporation is less . Thus thenet evapora tion rates are h igher dur ing droughts on two counts:(1) The increase in grOISS evaporation rates, and(2) the reduction in rainfal l which would normally offsetpart of the evaporation.

These higher evaporation rate IS further dep lete th e water supplies which alreadyhave been reduced by the low :streamflow following years of deficient ra infal l .The higher evaporat ion r at es a ff ec t not only water surfaces, but also the muchlarger areas of soi l and vegetation.The fourth item in the l i s t of climatic phenomena which generally character ize droughts is the relat ive humidity. Records of the relative humidity,

taken as the average percent at 12: 30 p.m., c. s t . , are ava ilable for a numberof s ta tions sca tt er ed over the State, for most of the per iod s ince 1940. Theserecords have been summarized for 14 of these stations as shown in the followingtabulation:

- 27 -


34/81

Comparison o f Rela tiv e Humidity for AverageConditions with that During DroughtsAverage Percentage (12:30 p.m. cst)

Long-Time Long-TimeAverage Relative Average RelativeRelative Humidity Relative HumidityStations Humidity ~ l Drought Stations Humidity in DroughtAbilene 470 41.0 El Paso 331 297Amarillo 45.0 390 Fort Worth 52.0 46.4Austin 551 50.8 Galveston 70.4 696Brownsville 597 574 Houston 59.2 56.6Corpus Christ i 61.9 590 Port Arthur 62.2 61.0Dallas 535 50.6 San Antonio 53.6 487Del Rio 530 48.6 Waco 549 52.6

The average relat ive humidity for the 14 stations for the entire periodwas 54.3 percent while for the drought period these stations had a compositeaverage of 50.8 percent. The relat ive humidity during the drought was 3.5percent lower than for the l o ~ s - t i m e period, which amounts to a reduction of6 percent in terms of the longo-time period. The nine inland stations werefound to have had an average difference of 4.4 percent in the relat ive humiditybetween the long-time average and the drought years, while the five coastalstat ions had a weighted difference of only 2.0 percent.

EFFECTS OF DROUGHT ON TEXAS ECONOMYAGRICULTURAL LOSSES

Agri cu lt ural l osse s in the State during the 1950-1956 drought were tremendous due to greatly reduced yields or, in some places, no crops at al l . Manyfarmers on the Rolling Plains and Edwards Plateau prepared the i r land andplanted seed during three consecutive years without harvesting a crop. Manyranchmen in these same areas have fed supplemental rat ions to the i r breedingherds almost the year around since 1951. The cat t le car ry ing capac ity o f mostof the rangeland was seriously depleted at the beginning of 1957 and even withyears of more plent i ful ra infa l l in 1957 and 1958 ful l rangeland recovery hasnot been ach:leved in a l l areas.Numerous data of the economic effect of th is recent drought are availablefor given subjects in speci fi c a re as . An overal l dollar-wise evaluation of

a l l the possible effects on the economy has not been made. The Texas Commissioner of Agricu lture in an address a t Amarillo in April , 1955 stated (inreference to the drought):"We have lost a minimum of 2 bil l ion dollars during this naturaldisaster -- or one-fourth of our agriCUltural potential. In other wordsthe equivalent of one entire year of production was wiped out by adversenature." (Based on fou r years of drought).

As the drought continued, an art ic le in the Houston Chronicle, January 17,1957, quoted the State Commissioner of Agricu lture as sta t ing the loss to

- 28 -


35/81

farmers during 1956 alone was 750 million dollars. From the above i t is seenthat for the years 1950-1954;. plus 1956, the agricultural losses w ere estimatedat $2,750,000,000. Since drought also was experienced in most parts of theState in 1955 it is indicated tha t the loss of crops alone exceeded 3 billiondollars during the 1950-1956 period. These estimates do not include losses toranchers, nor do they include secondary or indirect losses in the trading areas.I t is not the purpose of' th is report to present an estimate of the lossesthat ,rer e incurred during the drought. The preceding information is given onlyto i l lu s tra te the magnitude of losses which can occur during a drought. Ob-viously, when large losses are sustained over a series of years by two of theState 's basic econom ic groups, such as farming and ranching, a m arked impacton the State 's overall economy m ust resu lt . This impact during the recentdrought was state-wide as shown by the fact that 244 of the State 's 254 count ies were declared drought-disaster areas. Since the in tensity of the droughtvaried over the State, the impact of the drought on the economy of local orregional areas also varied.Local areas, where farming or ranching, or both, form the basic economy,had more serious econom ic pro"blems than the State as a whole. Only 15 countiesin Texas had populations exceed ing 100,000 in 1957 with the remain ing 239counties having populations ranging from about 98,000 to less than 1,000.While these la tte r counties have c it ies and tow ns with some diversification ineconom;)', the less populous counties generally are geared to an agriculturaleconomy. The counties which had an almost complete agricultural economysuffered most during the 19501956 period.The general effects of drought on agriculture and on the economy of anarea may be l is ted as follows:1 . A partia l or complete loss of crops (grains or cotton), resulting inloss of income.2. Overgrazing of rangelands and pasture, with consequent increased so i lerosion.3. Wind erosion of land following the removal or thinning of the vegetative cover.4. Selling out of herds, including breeding stock, usually at a loss.5. Loss of use of land after drought ends during the period of timerequired to restore land to fu l l use.6. Cost of beginning livestock operations again a f te r drought and mainta in ing operations until marketing of new stock is possible.7. Loss of tax revenue.8. Insect and pest increases (including grasshoppers) which usuallyoccur in wet years ,. immediately following drought.9. LOSf: of in come to commerce in local and regional trade areas.

- 29 -


36/81

10. Increased personal indebtedness incurred by farmers and ranchers,which will have a continuing effect in good ra infal l years following the drought.11. Cost of State and Federal drought re l ief .The effect of the drought on the financial resources of farm and ranchoperators was studied for specific areas of the State by A. &M. College. Forthe Edwards Pla teau a rea, ranc:hmen los t 38 percent of their net worth between

the fa l l of 1950 and the spring of 1954. This decline resulted from a 20 percent decrease in assets and a 37 percent increase in l iabi l i t ies .The A. &M. Study for the Edwards Pla teau a rea shows: (See ref . 14.)"Approximately half of the ranchers studied have reached the l imit oftheir credit" ."Ninety-seven ranchmen who obtained emergency loans in 1954 had beengranted short tenn credi t amounting to 206 percent of the value of theirl ivestock. ""It is reported that many banks in the area are making few additional agricultural loans and are shifting some high r isk credi t operations togovernment agencies"."Most fanners and small ranchmen are forced to obtain or seek outsideemployment since gross income from fanns and ranches no longer meets thecost of operation and family living".Other A. &M. information shows: (See ref . 14.)"Credit inst i tut ions have perfonned well during the drought. There hasnot been a bank failure in Texas attributable to drought-occasionedlosses; although in a fe"101 instances stockholders hae found i t necessaryto bolster their capital structure to maintain desired l iquidity"."Farmer I S Home Administration emergency credi t has been of inestimablevalue in local economics. This agency has kept many farmers in business.and i t has relieved the pressure on other credit organizations."

WINDSAll of the adverse affects of drought on agriculture are not caused by

lack of rainfal l , although there can be l i t t l e doubt that the ra infal l deficiency is the largest single item. Wind is another climatic factor whichalways contributes to the detriment of agriculture. This is a part of thevicious cycle which seems to operate in times of d rough t. Rainfall is scarce;clear skies prevail; temperatures increase; wind comes next, and disastrousso i l blowing follows.

The records contain statements concerning the des truc tion of crops, whichcan be ruined in a few days under the searing action of the dry winds, such asthe following:

- 30 -


37/81

Holliday, Archer Co. Dallas Morning News, Aug. 24, 1899, - page 4"Hot winds have prevailed for the past week, and as a consequenceeverything in the way of vegetation is either dead or fast dying . . . . "

More attention has been given to the other wind factor in which theresults are more spectacular. That is the movement of the so i l with the duststorms furnishing the visual evidence. It has been estimated by the SoilConservation Servi ce (s ee ref . 15) that during t he th ree-year period, 1954 to1956 from 10 million to 15 million acres were damaged by wind on the GreatPlains each year. I t is indieated that although the dust storms didn' t getas much publicity during the recent drought as they did in the Dust Bowl daysof the 1930'S, the acreage d a n ~ e d was about the same in both periods.

The cause and effect of the winds during droughts are pointed out by Hoyt,with the comment that p o s s i b ~ e damage is not the only resul t that may beexpected. The following quote is from W. S. P. 680, P 51."The principal causes of the disastrous soi l blowing in 1933 and 1934were continuous high winds, intensive cultivation, th e p ra ct ic es of burning stubble, low rainfal l , and lack of organic matter and so i l moistureto hold the so i l in placeThe surface material over large areas of the country, especially inthe arid and semiarid regions, consists in part of loess - that i s , windblown material that has been deposited throughout the ages and has alwaysbeen more or less subject to movement by winds when i t becomes dry ---Although the effects have been serious in many locali t ies , they wereprobably not as bad as would be indicated by the photographs and descript ions that appeared in press s ta tements .The great mantle of wind-blown s i l t that covers a large part of the

inter ior of the country indicates that dust storms have been a commonoccurrence in the geologic past . Although we are now chiefly concernedwith the damage done by .rind erosion in the recent dust storms, i t isinteresting to note that to these ancient s i l t deposits, called loess,is largely due the produetivity of the great farming regions included inthe Mississippi Valley, and there are many who believe that though theet'fecte: in the areas in '7hich the dust originates may be detrimental, theremay be counterbalancing benefits in areas in which i t is deposited."DROUGHT AID

Aid to drought-stricken flreas is not new. Local, State and Federalgovernments have in times past assisted families or groups affected by naturaldisasters such as floods, hurricanes, and tornadoes. Since drought i s also anatural occurrence, areas seriously affected by drought have also receivedfinancial assistance in the past.

Texas has experienced three periods of drought in which the State Legislature has found i t necessary to make appropriations for drought rel ief in theState. The f i r s t was in 1887 when $100,000 was appropriated for the "sufferersin the drought-stricken distr:Lct". In 1918 t he Leg is la tu re passed an act whichauthorized counties to purchal,e seed and feed for resident cit izens who wereunable to procure such seed and feed otherwise. I t appropriated $2,000,000 in

- 31 -


38/81

1918, and in 1919 added $1,000.,000 IllOre to carry out the purpose of the act .During ~ h 1950-1956 drought the Texas Department of Agriculture assis tedagencies of the Federal government in administering drought re l ie f . An emergency appropriation was approved by the 54th Legislature al lot t ing $43,500 tothe Texas Department of Agriculture to offse t increased expenses in the admini s t ra t ion of the Hay Program.

As the 1950-1956 drought progressed farmers and ranchers incurred progressively heavier f inancia l burdens. Range lands were unable to support evena frac t ion of the existing l ivestock and supplemental feeding measures wererequired. The prolonged continuation of the drought required ranchers tochange from supplemental feeding to subsistence feeding, which means thatpurchaEed feed formed the major part of the l ivestock food intake.

Ir . order to ass is t ranchers the U. S. Government ins t i tuted a drought-aidprogram in 1952, shipping in hay by rai lroad from points out of state whereversurpluE. hay was available. This hay was then sold to ranchers at reducedprices . During the year, July 1952-June 1953, 106,296 tons of hay were shippedin and sold under th is program. Data on hay prices without government ass is t -ance in the drought areas are not available but prices for hay in other partsof the State indicate this aid had a value of approximately $1,000,000.

A grain-feeding program was inaugurated in 1953 in place of the hayprogram. This govermaent-sponsored aid which continued through 1957, providedranchers with su rp lu s corn, wheat, oats , and cottonseed cake and pellets a tgreat ly reduced prices .The amount of di rec t assistance to ranchers during the 1953-1954 f i sca lyear was estimated from the nwnber of bushels of grain provided (U. S. Department o f Agric ultu re d ata) and from t he d if fe rence between the government se l l -ing price and the average market price at that time (Market News Service Data ).

On thiE; basis this di rec t assistance was estimated a t $9,384,000 for that year.Direct a ss is tance dat a for subsequent years were obtained from the AgriculturalStabi l iza t ion and Conservation office , U.S.D.A., a t College Stat ion:Fiscal Year Dir

a study of droughts in texas - twdb bulletin 5914 - december 1959

Documents