ANCH C. H, Pierc

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UNITED STATES DEPARTMENT OF THE INTERIOR Harold L. Ickes, Secretary LIBRARY

W. C. Mendenhall, Director WATER RESOURCES DIVK *C REPORTS SECTION Water-Supply Paper 796 G

MAJOR TEXAS FLOODS OF 1935

BY TATE DALRYMPLE AND OTHERS Q

Prepared in cooperation with the TEXAS BOARD OF WATER ENGINEERS

Contributions to the hydrology of the United States, 1937 (Pages 223-290)

UNITED STATES GOVERNMENT PRINTING OFFICE WASHINGTON: 1939

For sale by the Superintendent of Documents, Washington, D. C. Price 15 cents WATER RESOURCES DIVISION REPORTS SECTION

CONTENTS

Page Abstract______223 Introduction______224 Definition of terms_---_____-______227 Administration and personnel______227 Acknowledgments-______228 Physical features of Texas as related to the general character of the streams. 22& Determination of flood discharges______229» May flood on Seco Creek______232' Precipitation______.______233; Maximum discharge-______-___.______234 Previous floods ______236' June floods------______236- Precipitation____-______237" Colorado River Basin______239? Colorado River flood______239 Llano River flood______.-___ 241 Nueces River Basin.______. 245 Nueces River flood______245 West Nueces River flood______.______-___ 249 Determination of discharge near Brackett ville______252 Frio River flood______256 Atascosa River flood_____-______256 Rio Grande Basin____-_-_-______257 Stages and discharges of May and June floods __.-______257 Colorado River near San Saba______258 Colorado River at Austin______259" Colorado River at Smithville______26Q Colorado River near Eagle Lake______2621 North Llano River near Junction.______263; Llano River near Junction______264 Llano River near Castell______264' Pedernales River near Spicewood--___------__--_---_---_-_____ 266 Guadalupe River near Spring Branch_____-______-______266 San Antonio River near Falls City______267 Cibolo Creek near Falls City______267 Nueces River at Laguna______f ______268 Nueces River near Uvalde__--______-___-___-_-_-_-____ 2691 Nueces River at Cotulla______-______-__ 270 Nueces River near Three Rivers______272 Frio River at Concan______273; Frio River near Derby______-______274 Frio River at Calliham______275- Atascosa River at Whitsett______-______275 m IV CONTENTS Page December flood on Buffalo Bayou__.___-._____-__-_--_-_--_--_--_-._ 276 Precipitation______-_...______276 Maximum discharge------.---.----.__-__-.__-_--_------__ 277 Previous floods______._.______.____ 280 Summary of maximum discharges.______282

ILLUSTKATIONS

Page PLATE 54. Map of Texas showing principal towns and streams mentioned in the text-______.______224 55. Map of Texas showing major topographic divisions and major drainage basins______224 56. Llano River at Llano at about peak of flood of June 14, 1935- 240 57. Bridges destroyed by flood of June 14, 1935: A, Llano River on Mason-Fredericksburg highway; B, Nueces River on Uvalde-La Pryor highway_--____-_-___--__------___- 240 58. Isohyetal map of the major part of the Colorado and Nueces River Basins and parts of adjacent river basins.______240 59. Congress Avenue bridge, Colorado River, at Austin: A, At about peak of flood of June 15, 1935; B, At low water______240 60. A, Colorado River at Austin, looking north on Congress Avenue from right bank at about peak of flood of June 15, 1935; B, South Llano River at Junction, near peak of flood of June 14, 1935______-___-__--___---_--_-_----_--__ 248 61. Nueces River on Uvalde-La Pryor highway: A, View from left bank at about 10 feet below peak stage on June 14, 1935; B, View from right bank made about 30 minutes before bridges were destroyed. ______248 62. West Nueces River near Brackettville: A, Looking upstream from just below lower cross section; B, Looking toward right bank and upstream from about lower cross section.______249 FIGURE 34. Isohyetal map of the Seco Creek drainage basin above D'Hanis______235 35. Hydrographs of discharge, Colorado River near San Saba, at Austin, at Smithville, and near Eagle Lake, June 14-24, 1935______242 36. Isohyetal map of the Llano River Basin______244 37. Hydrographs of discharge, North Llano River near Junction, Llano River near Junction, and Llano River near Castell, June 14-17, 1935__--_-_-__--_ ____.-___-__-_---_-__-_ 246 38. Hydrographs of discharge, Nueces River at Laguna, near Uvalde, at Cotulla, and near Three Rivers, June 14-27, 1935_ -_----___---____--__---_---_-_-_-_--____,.___ 248 39. Isohyetal map of the West Nueces River Basin____-_-_--_ 251 40. Profiles of high-water marks and sections of slope-area reach on the West Nueces River near Brackettville-_____.__-- 253 41. Isohyetal map of the Buffalo Bayou Basin______278 42. Hydrograph of discharge, Buffalo Bayou at Eureka Cutoff railroad bridge at Houston, December 7-12, 1935______279 43. High-water and stream-bed profiles of Buffalo Bayou from Post Oak Road to the turning basin at Houston______281 CONTENTS " TABLES

Page TABLE 1. Precipitation records for June 1-15, 1935______238 2. Altitude and average descent of the Colorado River from a point near San Saba to the mouth______240 3. Maximum discharge at river-measurement stations on the Colo­ rado and Pedernales Rivers, June 1935______241 4. Altitude and average descent of the North Llano, South Llano, and Llano Rivers from source to mouth.______243 5. Maximum discharge determined at places in the Llano River Basin, June 1935______245 6. Altitude and average descent of the Nueces River from source to mouth______-______.____-____--___-_____ 247 7. Maximum discharge at river-measurement stations on the Nueces River, June 1935______249 8. Altitude and average descent of the West Nueces River from source to mouth______250 9. Computations for slope-area determination of discharge of the West Nueces River near Brackettville_____-.______--____ 252 10. Precipitation in Buffalo Bayou and adjacent drainage basins, December 6-8, 1935______. 277 11. Maximum discharge, Buffalo Bayou and tributaries, at Hous­ ton, December 9, 1935______.______277 12. Run-off and discharge on Buffalo Bayou at Eureka Cutoff Bridge, Houston, December 7-12, 1935______280 13. Crest stages, flood of December 9,1935, and stream-bed altitudes determined June 1929, Buffalo Bayou at Houston.. ______282 14. Maximum stages and discharges on certain streams in Texas.. 283 MAJOR TEXAS FLOODS OF 1935

By TATE DALRYMPLE and others

ABSTRACT In Texas in 1935 exceptional floods occurred in May on Seco Creek, in June on the Colorado and Nueces Rivers and their tributaries, and in December on Buffalo Bayou. A very heavy rainstorm occurred early in the morning of May 31 over the Seco Creek Basin. The maximum rainfall reported was 22 to 24 inches in B% hours. This extremely heavy rain occurred at the Woodward ranch about 17 miles above D'Hanis and 50 miles west of San Antonio. The resulting flood in Seco Creek exceeded any previously known. A slope-area measurement of dis­ charge made in a reach about 11 miles above D'Hanis gave a peak discharge of 230,000 second-feet from a drainage area of 153 square miles, or 1,500 second-feet per square mile. Heavy rains, amounting to probably 20 inches at some places, fell over the Colorado and Nueces drainage basins the first 2 weeks in June, causing floods greater than ever had been recorded in these basins. The greatest floods occurred on the Llano River, tributary to the Colorado, and the West Nueces River, tributary to the Nueces. The South Llano and Llano Rivers reached the highest stages ever known, the former stream being 3 feet higher at Junction and the latter 8.6 feet higher near Castell than the previous highest stages, which occurred in 1889. The South Llano River near Telegraph had a peak discharge of 160,000 second-feet from a drainage area of 540 square miles, and the Llano River near Castell had a peak discharge of 388,000 second-feet from an area of 3,514 square miles. The flood from the Llano River, when joined by a smaller flood from the Pedernales River, caused the Colorado River at Austin to reach a stage of 41.2 feet, which is 1 foot lower than the maximum stage of record, which occurred in 1869. The peak discharge of the Colorado River at Austin on June 15, 1935, was 481,000 second-feet from a drainage area of 26,350 square miles (excluding 11,800 square miles of noncontributing area). Below Austin there was little rain­ fall, and the flood peak decreased considerably. The maximum discharge of the West Nueces River at a reach about 28 miles north of Brackettville was 580,000 second-feet from a drainage area of 402 square miles, which is equivalent to 1,440 second-feet per square mile. So far as known this is the highest discharge ever recorded from an area of like size. The greatest recorded discharge on the Nueces River was near Uvalde, below the mouth of the West Nueces. At the river-measurement station at this place the peak discharge was determined as 616,000 second-feet; the drainage area is 1,930 square miles. The peak stage of 36.9 feet exceeded by 10.5 feet the pre­ vious maximum known stage, which occurred in June 1913. 223 224 CONTRIBUTIONS TO HYDROLOGY, 1937

A rain of 8 to more than 18 inches fell over the Sycamore Creek Basin, tribu­ tary to the Rio Grande a few miles below Del Rio, causing the greatest flood ever known on this stream. From December 6 to 8 torrential rainfall in the Buffalo Bayou Basin, in Harris County, amounted to over 20 inches in some places. The resultant floods in the Buffalo Bayou and tributaries exceeded previously recorded stages and caused considerable damage in the city of Houston. The maximum discharge of Buffalo Bayou at Lockwood Drive Bridge, below the mouth of Whiteoak Bayou, was measured as 52,750 second-feet from the drainage area of 458 square miles, equivalent to 115 second-feet per square mile. During the floods of May, June, and December, 1935, approximately 50,000 square miles of drainage area contributed extraordinarily high discharges and about 16,000 square miles contributed discharges greater than had been recorded previously. The information in this report includes records of peak stages and discharges and of mean daily discharges during the flood periods at about 19 river-measure­ ment stations, results of 25 peak discharge determinations, hydrographs of dis­ charge at 12 river-measurement stations, records of rainfall at 108 places, 5 isohyetal maps showing rainfall over various areas, and other data pertinent to the Texas floods. INTRODUCTION Texas is peculiarly subject to floods resulting from intense precipi­ tation, commonly called cloudbursts, over relatively small areas. Such floods occur in many regions, as they have recently in New York,1 in California,2 in Nebraska and Kansas,3 and in other places, and they occur more frequently in some regions than in others. Eastern and central Texas and certain sections of neighboring States appear to be especially subject to such floods. Every year Texas has several floods of greater or lesser magnitude caused by rains of the cloudburst type. Several exceptional floods, all associated with rainfall of unusual intensity, occurred in Texas in 1935. Out of this group, floods in five streams, caused by three distinct periods of high precipitation, have been chosen for presentation in this report, as follows: Seco Creek in May, the Llano, Colorado, and Nueces Elvers in June, and Buffalo Bayou in December. (See pi. 54.) There were other floods in the State in 1935, some of which may have been worthy of presentation if more facts had been available. So-called cloudburst floods are peculiarly difficult to describe satisfactorily. The intense precipitation may and very frequently does occur in a region where there are no rain gages and almost always in a region where there is no recording rain gage that would yield reliable information as to the intensity of precipitation. The infor­ mation on precipitation must therefore be compiled from available Johnson, Hollister, The New York State flood of July 1935: U. S. Oeol. Survey Water-Supply Paper 773-E, 1936. 'Troxell, H. C., and Feterson, J. Q., Flood in La Canada Valley, California, January 1, 1934: U. S, Qeol. Survey Water-Supply Paper 796-C, 1937. * Follansbee, Robert, and Spiegel, J. B., Flood on Republican and Kansas Rivers, May and June 1935: U. S. Qeol. Survey Water-Supply Paper 796-B, 1937. GEOLOGICAL SURVEY WATER-SUPPLY PAPER 7S6 PLATE 51

94° 106°

0 K L! A H 0

104° IOZ° 100° 96° MAP OF TEXAS SHOWING PRINCIPAL TOWNS AND STREAMS MENTIONED IN THE TEXT. GEOLOGICAL SURVEY WATER-SUPPLY PAPER 796 PLATE 55

______102"______IU i ~l ~l 7 ~ r ~ 1~ ~

102° W0°

MAP OF TEXAS SHOWING MAJOR TOPOGRAPHIC DIVISIONS AND MAJOR DRAINAGE BASINS. MAJOR TEXAS FLOODS OF 1935 225

sources, and, although it may be reasonably reliable, it is generally not closely accurate in regard to total quantity and largely fails to show the intensity of precipitation for short periods. Similarly, information as to rates of flood run-off is also largely lacking. Gen­ erally, there is no river-measurement station on the stream most affected. Except on the largest streams a flood may come and go within a few minutes or, at most, a few hours. Usually no oppor­ tunity is afforded for direct and accurate measurements of stage or discharge. The rates and quantities of discharge must be computed by indirect methods, such as by formulas for flow over dams of different shapes of crest, by the draw-down at contracted openings, or, most commonly, by open-channel slope formulas, and all informa­ tion used in such computations is obtained, of course, after the floods have passed. Difficult though the conditions may be, and unsatisfactory though the resulting reports may be, any available information with respect to cloudburst floods is of great value, because such floods are especially disastrous in creeks and small rivers, in which they yield record stages and discharges. Because of the inherent difficulties there is at best relatively little reliable information as to either their frequency or their magnitude. The Texas floods described in this report caused the loss of 30 lives and heavy property damage, amounting in the aggregate to over $28,500,000.* The greater part of the damage was caused by floods on the Colorado and Nueces Rivers and the area in Harris County tributary to Buffalo Bayou, including the city of Houston. May 1935 was a month of unusually heavy rainfall at many places in Texas, and the precipitation was well distributed over the State, with the result that most of the rivers reached flood stages. In the Monthly Weather Review for May 1935, page 170, the following statement is made: Except in the Rio Grande, where there was only a slight flood, there were moderate to severe floods in all the rivers of Texas which empty into the Gulf of Mexico. Ten persons were drowned. Heavy rainfall over parts of northeastern, central, western, and southwestern Texas during a period of several days near the middle of June produced disastrous floods on the Colorado, Guadalupe, and Nueces Rivers and less severe floods on the Rio Grande, Trinity, and other rivers. The Monthly Weather Review for June 1935, page 200, contains the following statement: There was a moderate flood in the upper Trinity River in Texas. This flood was most severe on the East Fork of the Trinity River, where levees were over­ topped and broken in many places. 4 See Monthly Weather Review, December 1935, pp. 364-365. 226 CONTRIBUTIONS TO HYDEOLOGY, 1937

The official in charge, Weather Bureau office, San Antonio, Tex., makes the following statements * * *: "Heavy to excessive rains over the watersheds of the Colorado, Guadalupe, and Nueces Rivers from June 12 to 16 caused severe floods in these river systems. The highest stages known occurred at Marble Falls, Austin, and Smithville, on the Colorado, and at New Braunfels and Victoria, on the Guadalupe; also at Cotulla, on the Nueces. "Timely warnings were issued for these floods, and large amounts of property saved thereby. * * * However, losses were heavy, especially to bridges and highways. Thousands of pecan trees were lost, and many farm buildings entirely disappeared. Eight people are known to have been drowned." There were widespread rains on June 13 in the lower Rio Grande Valley. The heaviest 24-hour fall of record occurred at Del Rio, Tex., and a very rapid rise in the Rio Grande followed. The Rio Grande had previously reached the flood stage at Mercedes and Brownsville. The property damage was not heavy, but four persons were drowned when their home was washed away. The flood on Buffalo Bayou at Houston in December is described in the Monthly Weather Review for December 1935, page 361, as follows: The outstanding flood of December 1935 was the record-breaking overflow of Buffalo and Whiteoak Bayous at Houston, Tex., on the 8th and 9th. This destructive flood was caused by excessive rainfall over Harris County, Tex., during a 42-hour period on the 6th, 7th, and 8th, with amounts ranging from 5/4 inches at Houston to approximately 20 inches near the center of the 406 square mile watershed. The following report made by the Weather Bureau office at Houston, Tex., is of interest: "Torrential rainfall over Harris County on December 6, 7, and 8 caused phe­ nomenal rises in Buffalo and Whiteoak Bayous. These streams have their courses almost entirely in Harris County, and their confluence is near the center of the wholesale district of the city of Houston. The Buffalo Bayou flows through the center of the city and enters into Galveston Bay. The lower course from the eastern part of the city to Galveston Bay has been deepened to form the Houston Ship Channel. There has been the usual encroachment on the channel through the city, and this operated to retard the flow of flood waters and caused excep­ tionally destructive flooding in the business district, as well as in some residential districts. More than 100 city residential blocks were flooded. Homes had to be abandoned, and much hardship followed. Fortunately, mild weather prevailed. Eight persons were drowned. The property loss is conservatively estimated at $2,500,000, consisting of damage to roads, bridges, buildings, and contents. Several buildings in the wholesale district were completely wrecked by the under­ mining of their foundations. Stocks of goods in several warehouses were ruined. "The greatest 24-hour rainfall in Houston was 5.38 inches on the 7th and 8th, but the catch in a standard rain gage exposed at Satsuma, a pumping station of the Humble Oil Co., in the northwestern part of Harris County, was 16.49 inches, and catches of 21 inches were reported, but these were measured in improvised gages and cannot be accepted as entirely reliable. "Levels run by the city engineer show a stage of 40.3 feet above mean tide level immediately below the confluence of the Buffalo and Whiteoak Bayous, as compared with 34.3 feet on May 31, 1929, and 34.3 feet in 1879 (date unknown). The crest passed in the early morning of December 9." The determinations of discharge for the peak stages of these floods necessarily were made from field data collected subsequent to the MAJOE TEXAS FLOODS OF 1935 227 floods. In general the field data consisted of measurements of slopes and areas of cross sections corresponding to high-water marks and the determinations of proper values of the roughness factor n for use in the Kutter or Manning formula. The computations of discharge by slope formulas, using the best information obtainable for slopes, cross sections, and values of n, indicate that not only were these floods of unusual magnitude, but some of the rates of discharge in second-feet per square mile of drainage area were greater than any determinations previously made for areas of similar size in Texas or elsewhere in the United States.

DEFINITION OF TERMS The volume of water flowing in a stream the "run-off" or "dis­ charge" is expressed in various terms, each of which has become associated with a certain class of work. These terms may be divided into two groups (1) those that represent a rate of flow, as second- feet, gallons a minute, miner's inches, and discharge in second-feet per square mile; and (2) those that represent the actual quantity of water, as run-off in inches of depth on the drainage basin, acre-feet, and millions of cubic feet. The principal terms used in this report are "second-feet," "second-feet per square mile," and "acre-feet." They may be denned as follows: "Second-feet" is an abbreviation for "cubic feet per second." A second-foot is a rate of flow of 1 cubic foot per second, or the rate of discharge of water flowing in a channel when the cross-sectional area is 1 square foot and the average velocity is 1 foot per second. It is generally used as a fundamental unit from which others are computed. "Second-feet per square mile" is the average number of cubic feet of water flowing per second from each square mile of area drained, on the assumption that the run-off is distributed uniformly as regards both time and area. An ''acre-foot," equivalent to 43,560 cubic feet, is the quantity required to cover 1 acre to the depth of 1 foot. This term is com­ monly used in connection with storage for irrigation. "Stage-discharge relation" is an abbreviation for the term "rela­ tion of gage height to discharge." "Control" is a term used to designate the natural section, reach of the channel, or artificial structure below the gage, which determines the stage-discharge relation at the gage. "Isohyetals" or "isohyetal lines" are lines joining points on the earth's surface having equal depths of rainfall in a given interval of time. ADMINISTRATION AND PERSONNEL The field and office work incident to the preparation of this report was performed by the water-resources branch of the Geological 228 CONTRIBUTIONS TO HYDROLOGY, 1937

Survey, under the general administrative direction of N. C. Grover, chief hydraulic engineer, and C. G. Paulsen, chief of the division of surface water. The field work and the collection and tabulation of the basic information with respect to stages and discharges were done by Tate Dalrymple and others, under the immediate direction of C. E. Ellsworth, district engineer. The general technical direction of the special work and assembling of the report was carried on under the division of water utilization, R. W. Davenport, chief.

ACKNO WLED GMENTS The river-measurement work of the United States Geological Sur­ vey in Texas is carried on in cooperation with the State Board of Water Engineers, C. S. Clark (chairman), A. H. Dunlap, and John W. Pritchett. Acknowledgment is made to the United States Weather Bureau for many of the data on rainfall and storms, and to M. J. McCall, of the county engineers' office, Harris County, and the engineering depart­ ment of the city of Houston for most of the data on the Houston flood. Many miscellaneous rainfall records were obtained from local ob­ servers to whom no individual acknowledgment is made but to whom special credit is due, for these data have added very materially to the knowledge of the rainfall. Information appearing in this report has been obtained from many supplemental sources, including individuals, corporations, and city officials. So far as practicable, acknowledgments for individual con­ tributions are given at appropriate places in the report. PHYSICAL FEATURES OF TEXAS AS RELATED TO GENERAL CHARACTER OF THE STREAMS Texas may be divided topographically into three general regions the Staked Plains, the Central Plateau, and the Coastal Plain. (See pi. 55.) The dividing lines between these sections are the Cap Rock and the Balcones fault zone, at each of which there is a pronounced change in the topographic character. The Staked Plains extend from the Cap Rock to the northern and western boundaries of the State. This region is comparatively flat, ranges in altitude from 2,500 to 4,000 feet, has very few trees and not many streams, and receives a sparse rainfall. It contributes little if any run-off to the lower reaches of the river systems that head in it. The Central Plateau ranges in altitude from 800 to 2,500 feet, consists mostly of low hills, is fairly well wooded, has a considerably greater rainfall than the Staked Plains, to the northwest, and the rain that falls on it feeds many streams. The southern and eastern edge of this region lies along the Balcones fault zone, which forms the boundary between the Central Plateau and the Coastal Plain. This MAJOR TEXAS FLOODS OF 1935 229

fault zone crosses the State from a point near Dallas through Waco, Austin, and San Antonio to the Rio Grande at Del Rio. The escarp­ ment along this fault is a rather prominent topographic feature from Waco to Del Rio. The rise from the Coastal Plain to the plateau ranges from 200 or 300 feet to over 1,000 feet and is rather abrupt over much of its course. This fault area is characterized by steep slopes and shallow rocky soil, with narrow flood plains along the streams. The Coastal Plain region, extending from the Balcones fault zone to the Gulf of Mexico, consists mostly of rolling flat hills in the inland part and of relatively flat areas along the coast. A large part of the eastern section is covered with timber. Much of the Coastal Plain is devoted to farming and is more densely populated than the other sections of the State. The streams in this region are comparatively large and have wide overflow channels.

DETERMINATION OF FLOOD DISCHARGES On the lower reaches of the streams the peak discharges for the floods of 1935 were determined by stage-discharge ratings based on current-meter measurements, but on the upper reaches peak discharges were obtained by slope-area methods. There are few opportunities on Texas rivers for computing flow over dams or falls or through contracted openings. In selecting a site for a slope-area determination of discharge the following factors were considered and the best possible selections made: (1) Straightness of channel, (2) concentration of flow in uniformly deep, narrow channel, (3) adequate length of reach, (4) permanence of channel during flood, (5) absence of trees, brush, and other obstructions, (6) uniformity of cross sections and slope, (7) quality and quantity of high-water marks, (8) favorable approach and get-away conditions, (9) freedom from debris movement, and (10) uniformity of bed slope. After the tentative selection of a site, levels were run to determine the altitude of the high-water line on both banks over the length of the reach selected. A profile of the high-water points so obtained was plotted in the field, and a study made of the uniformity of the indicated surface slopes. If a sufficiently long reach was found to have satisfactorily uniform slopes on both banks, two or more cross sections were surveyed in the reach. If the slopes were not uniform, another measuring site was selected and investigated in a like manner; this procedure was followed until a satisfactory reach was found. Photographs were made of the reach finally selected, enough views being taken to show the pertinent characteristics of the channel. Close attention was paid to the evidence of debris carried by the stream. In some places a considerable quantity of gravel may have been moved by the stream in flood, but in this investigation no place 230 CONTRIBUTIONS TO HYDROLOGY, 1937

was found in which the quantity appeared sufficient to affect the accuracy of the measurement appreciably. The computations for determining the discharges were made in the office after all field data had been obtained. For each slope-area measurement profiles of the altitude of the high-water marks were plotted, and the surface slopes were determined. The cross sections were also plotted, and the characteristics of each part of the channel were described by notes. In computing flood discharge by the slope-area method the average velocity in feet per second was determined either from Manning's formula, v=s 1.486 « n or from Kutter's formula, 0.00281 ,1.811 V=

J in both of which V= average velocity, in feet per second. n= coefficient of roughness. r=hydraulic radius, in feet, equivalent to area of cross section divided by wetted perimeter (w. p.}. s=slope of energy gradient. Originally Kutter's formula was used for determining discharges by the slope-area method, but owing to its greater simplicity Mann­ ing's formula has been used for later determinations and for recompu- tations of previous slope-area measurements. Guidance in the selection of values of n, the coefficient of roughness, has been obtained from figures computed from measurements of discharge by current meter and measurements of slopes. Such studies of the value of n have been made at various river-measurement stations over the State. The results have been compared and checked against the general experience in the use of this coefficient elsewhere in this country. Cross sections of reaches of channel were divided into parts to provide for variation in the hydraulic radii and coefficients of rough­ ness in the different parts. Where a subdivided part of a channel was bounded by dense vegetation or trees, such boundary was treated as a part of the wetted perimeter. At many points, owing to a difference in the area of the upstream and downstream cross sections, it was necessary to consider the velocity head and to correct the surface slope to a value representing MAJOR TEXAS FLOODS OF 1935 231 the energy grade line. Where the velocity at the downstream sec­ tion was less than at the upstream section, it was assumed that there was a 50-percent recovery of the theoretical kinetic-energy head. The application of the slope-area method is shown by computa­ tions for discharge of the West Nueces River near Brackettville (table 9, p. 252). The mean daily discharge and the volume of run-off were com­ puted at all gaging stations on the flooded streams. The discharge is treated as a function of the stage, or gage height. The discharge for an appropriate interval of time was found by taking the mean gage height for that interval and applying it to the rating curve. Rating curves were developed from discharge measurements at the station by plotting discharges as abscissas and gage heights as ordinates. Efforts were made to obtain sufficient data to determine the stages satisfactorily and to define the rating curves throughout the range of stages observed. The stilling wells at several float-recorder stations were destroyed, and the chart records for the flood lost. At these stations careful inquiry was made of local residents as to the time of flood stages observed by them, and the altitudes in relation to the gage were determined by levels. Generally such stations were visited by an engineer within a day or two after being destroyed, while the details of the flood were still fresh in the minds of local residents. The gage-height records obtamed in this manner are subject to possible error but are the best obtainable under the circumstances. The figures of discharge computed at such stations were carefully com­ pared with records at other stations on the same or adjacent streams, in order to avoid large errors. In constructing a rating curve from which the discharge is com­ puted, the curve must often be extended beyond the point defined by current-meter measurements to the point defined by the determination of peak discharge by some less reliable method. The logarithmic plotting of stage and discharge has been found helpful in drawing a rating curve. This method is especially helpful in interpolating or extrapolating a rating curve for any considerable range in stage. The graph of the relation thus developed usually tends to be a very flat curve or nearly a straight line, provided certain adjustments are made to the observed gage heights to make them conform to the physical conditions of the site. This adjustment consists of the ad­ dition or subtraction of some constant amount, which is determined by a study of such conditions. For example, at a river-measurement station with a riffle control of uniform depth to the bed across the channel, the gage height of zero flow should be subtracted from each observed gage reading. The straight line or flat curve usually produced 232 CONTRIBUTIONS TO HYDROLOGY, 1937 may be extended within appropriate limits without great error pro­ vided no marked changes take place in the cross section within the range of such extension. In a logarithmic extension the measure­ ment of peak discharge may not seem consistent with the relation indicated by lower measurements. In such circumstances, after a study of the control section or reach, the direction of the rating curve was usually changed at or near the gage heights corresponding to the stages at which the characteristics of the control changed. After the logarithmic rating curve was drawn it was transferred to rectangular coordinates. MAY FLOOD ON SECO CREEK GENERAL FEATURES Seco Creek rises in southwestern Bandera County at an altitude of about 2,000 feet, flows southeastward across Medina and Frio Coun­ ties, and at an altitude of about 600 feet joins Hondo Creek, a tribu­ tary of the Nueces River through the Frio River. Seco Creek is about 60 miles long. At D'Hanis (population 400), about 50 miles west of San Antonio and 20 miles above its mouth, the creek is crossed by the Southern Pacific Railroad. The creek crosses the Balcones fault zone a few miles above D'Hanis. Above the fault zone the country is hilly, sparsely wooded, and utilized mostly for ranching. For a dis­ tance of about 8 miles above D'Hanis Seco Creek is parallel to Parkers Creek, which is from 2 to 3 miles to the east. Between these two creeks the country is low, fairly level, and almost entirely cultivated. East of Parkers Creek and west of Seco Creek there are low hills. A heavy rainfall over the Seco drainage basin above D'Hanis in the early morning of May 31 caused the creek to rise rapidly and reach a stage much greater than ever known before. About 6 miles above D'Hanis the stream overflowed and merged into Parkers Creek. Be­ tween this point and a point below D'Hanis Seco Creek covered the country between the two streams, with the concentration or main thread of the current swinging from side to side in the combined valleys and destroying houses, fences, crops, and livestock. A very small part, perhaps 2 percent, of this water came from Parkers Creek. The following account is quoted from an article by Miss Josie Rothe in the Hondo Anvil Herald of June 7, 1935: In the business section [of D'Hanisl the water reached its highest stage about 10 a. m. [May 31], having risen rapidly for several hours. At 7 o'clock water was flowing into basements, and it continued to rise until it stood from 1 to 3 feet deep in the business houses. * * * Both the Seco and Parkers Creeks broke out along new courses, and near their banks homes that had never been in danger before were flooded at this time. * * * Hardly a house anywhere near the Seco escaped the overflow, which carried with it the homes of hundreds of Mexi­ cans, together with all their clothing and household goods. The greatest tragedy of the day was the loss of lives of four Mexican children. * * * About 1 mile of railroad track was washed out and the rails twisted beyond belief; a boxcar MAJOK TEXAS FLOODS OF 1935 233 floated away, * * * automobiles, fences, wash houses, car sheds, cattle, mules all were swept along by the terrific current. * * * A cyclone and severe electrical storm accompanied the rain, putting out telephone and telegraph lines and isolating the town for several hours. The total amount of the damage done by the flood on Seco Creek is not known. Many houses, fences, roads, small bridges, and other improvements were destroyed. Crops were destroyed and livestock drowned. Household goods, merchandise, automobiles, and other personal goods were considerably damaged by submergence. The damages by this flood are included in the total shown for the Nueces River Basin for June on page 237. The damage to the Southern Pacific Railroad amounted to $32,500, and to the State highways $16,000. Four children and one woman were drowned.

PRECIPITATION There are no United States Weather Bureau rainfall stations in the Seco Creek drainage basin, and comparatively little reliable infor­ mation as to precipitation is available for this storm. All receptacles ordinarily used for measuring rainfall ran over or were washed away. The following information was obtained: 1. Lutz ranch, 2% miles above D'Hanis: Mr. Lutz reported 12.5 inches of rain measured in a can; rained from 3:45 to 5:00 a. m. May 31. 2. A. Rothe ranch 11 miles by road above D'Hanis: Armin Rothe measured in a standard United States Weather Bureau type gage 9.56 inches of rain from 11:00 p. m. May 30 to 8:00 a. m. May 31 and 0.26 inch from 8:00 a. m. to noon May 31. Most of this rain probably fell between 5:00 and 8:00 a. m. May 31, but the gage was not read between 11:00 p. m. May 30 and 8:00 a. m. May 31, A record of rainfall has been obtained at this gage since 1880. 3. Woodward ranch, 17 miles by road above D'Hanis: Mr. Smith, ranch man­ ager, reported that 22 to 24 inches of rain fell in 3J^ hours, from 1:45 to 5:15 a. m. May 31. This estimate was based on measurements in a masonry trough and in a large paint can. Mr. Smith also furnished the following information obtained from different ranches: 16 inches of rain about 4 miles west of the Woodward ranch, 16 inches about 5 miles northwest of the Woodward ranch, 15 inches about 3 miles north of the Woodward ranch, 6.5 inches about 6 miles north of the Woodward ranch, 11 inches about 6 miles northeast of the Woodward ranch, and 6 to 7 inches about 8 miles west of the Woodward ranch. 4. Tarpley, about 23 miles due north of D'Hanis and just east of the Seco Creek drainage basin: C. G. Leighton measured 5.38 inches of rain on May 31 in a glass jar 12 inches deep, 7 inches in diameter, and flat on the bottom. He has kept a record of rainfall at Tarpley for many years. 5. D'Hanis: Various reports range from 12 to 14 inches; no actual measure­ ments made. 6. Sabinal, about 12 miles west of D'Hanis: 7.70 inches between 5:00 and 11:00 a. m. May 31, United States Weather Bureau station. 7. Hondo, about 9 miles east of D'Hanis: 9.15 inches between 5:00 a. m. and 11:00 a. m. May 31, United States Weather Bureau station.

58805 39 2 234 CONTRIBUTIONS TO HYDROLOGY, 1937

J. H. Jarboe, official in charge of the United States Weather Bureau office at San Antonio, made a survey of the area above D'Hanis and submitted the following report to the Geological Survey: The number of rainfall measurements is too small to support a definite state­ ment of amounts. The circular tank at the Woodward ranch, cleaned and dry before the rain as affirmed by all, is the best measurement obtained. This tank holds 21.84 inches and ran over in less than 3 hours. Carbide can holds 11.50 inches, ran over at the Lutz ranch. All ranchmen state that rain fell in less than 3 hours. Using the high crest stages reached at the different ranches as part evidence, the following conclusions have been reached: That apparently 20 inches or more rainfall occurred over a small area on the Seco Creek, approximately 12 miles above D'Hanis, and that 12 to 14 inches occurred at other points, with an average amount of more than 9 inches over the entire watershed of approximately 80 square miles,5 and that the time required for the rain was less than 3 hours. Figure 34 shows the drainage area of Seco Creek above D'Hanis and isohyetal lines for the rain of May 31 as estimated from available information. MAXIMUM DISCHARGE A reach of Seco Creek at the Eothe ranch, about 11 miles above D'Hanis, was selected for making a discharge determination by the slope-area method. The right bank at this point was overflowed for a quarter to half a mile, but there was not much flow outside the chan­ nel, as the depth of water was not great and the velocities were low, as indicated by small erosion in fields and by statements of observers. The discharge in the overflow area was estimated as about 8 percent of the total. Slopes were determined over a length of about 1,800 feet by levels to high-water marks on the left bank, which indicated a uniform slope over a distance of about 1,100 feet. Two cross sec­ tions 700 feet apart were measured in the reach of uniform slope. As the lower cross section was about 21 percent smaller than the upper section, a velocity-head correction was applied. There was evidently some movement of gravel in the main channel during the flood, but the amount was not considered sufficient to affect the discharge appreci­ ably. The peak discharge was computed as 230,000 second-feet. The drainage area above the slope reach, measured on the Hondo and Bandera topographic maps of the Corps of Engineers, U. S. Army, is 153 square miles, which indicates that the peak discharge per square mile was 1,500 second-feet. There is no river-measurement station in the Seco Creek drainage basin at which continuous and systematic records of stages and dis­ charges are kept. Some indication of the quantity of water passing down the creek may be had from the records of mean daily discharge 6 Later measurement shows this area to be 153 square miles. MAJOE TEXAS FLOODS OF 1935 235

Number refers to discharge measurement station In table 14 Rainfall stations. May 31, I Lutz ranch 12.5 In. A. Rothe ranch 9.82 In. Woodward ranch 22 to 24 In Tarpley 5.38 In. D'Hanis 12 to 14 In. Sabinal (TJ.S.W.B.) 7.70 In. Woodward ranch, 4 ml. W., 16 In Woodward ranch, 5 ml Woodward raiich, 3 ml Woodward ranch, 6 ml Woodward ranch, 6 ml. HE., 11 In

FIGURE 34. Isohyetal map of the Seco Creek drainage basin above D'Hanis, showing total rainfall, in inches, observed May 31,1935. 236 CONTRIBUTIONS TO HYDROLOGY, 1937 of the Frio River at Concan (p. 273) and near Derby (p. 274), river- measurement stations above and below the mouth of Seco Creek. However, the difference in the discharge of these two stations repre­ sents the discharge from some other streams in the intervening drain­ age area besides Seco Creek.

PREVIOUS FLOODS The flood of July 1932 was the highest on Seco Creek for many years prior to that of May 31, 1935. F. H. Wolff, who lives in a rock house built in 1873 in the eastern part of D'Hanis just west of Parkers Creek, stated that the highest water between 1873 and May 1935 occurred in July 1932, when the water came to his doorstep. In May 1935 the water was more than waist deep inside the house. A slope- area measurement of the 1932 flood at the Lutz ranch, 2% miles above D'Hanis, gave a peak discharge of 35,800 second-feet, or 212 second- feet per square mile. The following reference to a previous flood is quoted from the Hondo Anvil Herald for June 7, 1935: Mr. Wolff is the son of a pioneer settler at D'Hanis and says that since the founding of D'Hanis in the late 40's there has never been a flood in the valley that approached this one [May 31]. He recalls, however, a conversation he had when a boy with an old frontiersman, who ranged over this country before perma­ nent white settlements had been attempted, in which the old man told him of seeing drift high up on the side of Cross Hill, and he warned him D'Hanis and the Seco Valley might some day see another such flood. His prophesy seems to have been fulfilled in the flood of May 31, 1935. A section was cut from a live oak tree which was undermined and fell within the reach where the slope-area measurement was made, and 95 annual growth rings were counted. From the position of this tree in relation to the channel it was inferred as probable that no flood as great as that of May 31, 1935, had occurred in nearly a century. A flood on July 24, 1935, less than 2 months after the flood of May 31, reached a stage at the Lutz ranch only 3 inches lower than that of July 1932. Eight or nine inches of rain was measured at the A. Rothe ranch, about the same as on May 31, but there was only a light rain in the basin above. JUNE FLOODS

GENERAL FEATURES Heavy rains over the Colorado and Nueces drainage basins caused floods in June 1935 that were greater than had been known before. The Llano Eiver, tributary to the Colorado, and the West Nueces River, tributary to the Nueces, experienced extraordinary floods. Although record-breaking stages occurred, none of the reported rain­ fall appeared to be particularly excessive or intense when compared MAJOR TEXAS FLOODS OF 1935 237 with other rains in Texas. There had been general rains in the region for 6 weeks before the flood, and all streams were above normal stage. Heavy rains, ranging between 4 and 12 inches, fell in the 24 hours before the floods. Fortunately the rapid rises and high stages did not result in loss of life, but great amounts of property were destroyed. The damages would have been far greater if there had been any cities within the flooded region. Volume of run-off and maximum discharges for the flood period in June were computed for all river-measurement stations in the flooded region. At other places peak discharges were determined by the slope- area method, but data were insufficient for computing the volume of run-off. There were few official rainfall records in the area, but unofficial records were compiled from many sources. There were no recording rain gages in the region of great precipitation, and consequently no records of intensity for short periods are available. The Monthly Weather Review for December 1935, pages 362-365, gives the total losses for the year in the Colorado River Basin as $12,956,500 and in the Neuces River Basin as $9,345,000. These losses in the Colorado River Basin include $221,000 that was not due to the June flood, and those in the Neuces River Basin include the loss due to the flood of May 31 in Seco Creek. The total damage to railroads amounted to $444,390, and the damage to the highway sys­ tem as reported by the State Highway Department was $1,897,000. The State Highway Department estimated the loss caused by the destruction of major bridges as about $1,424,000. Plate 56 presents views of the Llano River at Llano. One span of the highway bridge that fell into the river was found several miles downstream after the flood had subsided. Plate 57 gives views on the Llano and Nueces Rivers where bridges were destroyed.

PRECIPITATION There were no standard rain gages in the West Nueces River Basin and few in other basins affected by the June floods. In the West Nueces area all cans, buckets, and other receptacles ordinarily used to measure rainfall were filled and running over, and some were washed away; in the upper part of the basin fairly reliable information was obtained from measurements made in rock tanks. The total rainfall for the period June 1 to 8 and the daily and total rainfall from June 9 to 15 are given in table 1. Plate 58 is a map showing isohyetals for the area most affected by the storm for the period June 9 to 15. The available information in some regions was insufficient for a highly accurate determination of isohyetals. There were several small areas on which the rainfall was greater than that indicated on plate 58, but no satisfactory records of the amounts 238 CONTRIBUTIONS TO HYDROLOGY, 1937 could be obtained. A heavy rain, probably 10 to 20 inches, fell in a- few hours on June 13-14 over the Barrons Creek Basin above Freder- icksburg. Considerable damage was done to highways and county roads, and several bridges were destroyed in that small basin. Creeks a short distance from Barrons Creek showed only moderate floods, indicating that the very heavy rain must have been confined to a 1 comparatively small area. At Cleo, in Kimble County, a heavy rain is known to have fallen over a small area, but no information was obtained of the amount. Undoubtedly there were other similar localities of heavy rainfall of which information is lacking. In the following table "T" indicates precipitation less than 0.01 inch, and "leaders" indicate zero precipitation. TABLE 1. Precipitation, in inches, prior to floods of June 1935

June

1-8 9 10 11 12 13 14 15 9-15

Weather Bureau records: 1.. __ ...... 4.10 1.14 1.69 2.65 0.33 5.81' 2- ____ ...... 5.15 T T 1.21 .96 0.28 1.89 4.34- 1.32 0.17 .90 .30 .34 1.42 .04 3.17 4 _____ . _ . Big Wells. __ . ___ ... 2.57 1.25 .24 .19 .33 .79 2.80' 5 ...... 1 «4 T .29 2.12 .05 .27 2.73 6 ...... 1.99 1.42 .76 2.11 4.29' 7 ...... 1.55 .07 .15 .26 2.20 .91 1.40 2.00 6.99 8. __ . __ ... 2.01 T 1.26 .04 .95 1.00 .04 3. 29 8 ...... 1.57 .13 .55 .07 .08 .83 10 . - 1.55 .06 .62 .23 .33 .18 .90 2.32 11 1.88 .40 .09 .49- 12 . 3.48 .90 1.22 .50 2.62 13 _ .. 1.58 .71 .30 .71 1.11 2.83. 14...... __ . 9 fvi .05 .02 1.78 .32 T 2.17 15 _ ...... Del Eio.... __ . __ .... 1.56 .46 .49 2.06 .21 8.79 .13 T 12.14 16 . ... Dilley. ... 3.78 .06 .50 .44 1.39 .04 1.10 3.53 17 ... _ ...... 62 .45 2.09 .24 .33 .37 3.48 18 Eden.... _____ ..... 2.88 .15 1.13 .52 .26 .19 2.25 19 1.42 1.30 .70 .40 1.14 .04 1.33 4.91 20 _ . ... 2.34 T .03 .59 .51 2.70 .43 4.26- 21 _ ...... 62 .22 .01 .44 .99 .06 1.72 22 ... 1 Q1 1.25 1.25 1.15 1.18 4.83 23 . .82 .18 .95 .22 1.01 2.75 .05 5.16- 24 .63 .06 1 34 .66 T 2.06 25 Hallettsville 1.04 T .61 .90 T 1.51 26 ...... 1.42 .34 1.77 2.70 .95 .93 .57 7.26- 27 ... .31 T .04 .10 .70 1.50 4.90 7.24 28 2 fifi T .76 .40 .10 6.00 T 8.81 29 ... .84 .98 .60 .10 9.75 .25 11.68 30 1.27 .68 .48 .12 1.79 2.47 3.90 9.44 31. _ ... 1.33 .57 .43 .45 .36 .09 1.90' 32 ...... 2.66 .56 .58 1.46 2.60 33 2 34 .41 .47 .65 .53 .36 .45 2.87 34...... _ .. 1.94 .04 .93 .03 .75 T 1.50 3.25 35 2.80 .16 .02 2.15 1.30 3.23 6.86 36 . .76 .58 1.25 1.67 .15 3.65 37 .. 2.30 1.60 1.00 1.67 4.27 38 . 1.33 .55 .79 .62 .20 1.12 3.28 39 ...... 1 OQ OA .68 3.62 2.05 .67 8.82 40 ...... 2.18 .11 .32 1.20 1.13 5.92 .43 9.11 41 ...... 37 T .40 .03 .82 1.27 .16 1.02 3.70 42. _ ...... 40 .26 .11 .03 1.04 3.80 T .10 5.34 43 ...... 1.21 1.45 1.02 .93 3.40 44. _ ..... __ . 1.26 .86 .91 1.05 1.25 .25 .53 1.75 6.60 45 - Rocksnrinss _ .... 1.60 1.30 .50 .75 9.50 12. 05- MAJOR TEXAS FLOODS OF 1935 239

TABLE 1. Precipitation, in inches, prior to floods of June 1935 Continued

June

1-8 9 10 11 12 13 14 15 9-15

46...... 1.04 T .55 .03 .77 5.46 .10 6.91 47...... 1.77 .40 .60 1.20 1.25 .35 .45 4.25 48...... 1.04 .42 1.15 .21 2.18 2.00 1.03 .38 7.37 49...... 2.12 T .85 .95 .51 2.31 50... ______...... 46 .01 .02 .03 .66 3.17 21 .59 4.69 51...... Sinton. _____ ...... 50 .02 .10 .40 1.25 .01 1.78 52...... 1.25 .17 .53 .08 2.32 2.95 6.05 53...... Smithville...... 99 .02 .83 .60 T .16 1.61 54...... Substation 14...... 4.07 .05 3.60 .15 .31 1.75 T 5.86 55...... TayJor. _____ . __ . 2.47 .39 .73 .89 2.01 56...... Temple- ______2.61 .27 .64 1.20 2.11 57...... 2.31 1.33 .44 .30 5.37 .15 .04 7.63 58.. ___ ...... 51 .73 .40 .50 1.27 1.32 .20 4.42 59...... Whitsett...... 73 .54 .60 6.00 7.14 60 _ ...... 25 2.57 .34 3.16 Supplementary records: 61... _ ...... 2.76 .25 .88 2.00 .88 2.31 6.32 62...... 1.75 1 10 1.00 .06 2.25 63...... 1.84 .13 (< ) (a\ (a\ C) C) 4.97 5.10 64...... _ .. 1.38 1.06 2.05 .79 .50 .05 4.45 65...,. _ . __ . 2.90 1.00 .90 1.65 1.15 .08 4.78 66...... 9 sn («) fa\ C) (a) 7.50 7.50 67...... 1 97 1.32 .32 1.14 .56 6.86 .30 10.50 68...... _ . 1.00 1.75 .50 .75 2.50 .75 .75 1.33 8.33 69 . east ...... 1.03 1.08 .77 .28 7.30 .14 9.57 70...... 2.65 C) 2.65 2.65 71 1.06 .88 .38 1.38 1.25 .88 6.33

No. on pi. 58 Locality Miscellaneous records

72...... 73..... _ . 74...... 75...... Carta Valley ______. 76.. ... 77...... Carta Valley...... 78...... 79. 80. ... 81...... 82...... 83.... __ . 84. ____ . May, 4 inches; June 1-12, 6 inches; June 13-14, 10 inches. 85. north. 86...... ISFoxville 87...... 88...... 89... .

Rainfall included in the next measurement. COLORADO RIVER BASIN

COLORADO RIVER FLOOD The upper part of the Colorado River drainage basin lies in eastern New Mexico near the Texas line, at an altitude of about 4,000 feet. The river flows southeastward across Texas and enters the Gulf of Mexico near Matagorda. Its total length is about 600 miles, and its 240 CONTRIBUTIONS TO HYDROLOGY, 1937 drainage area is 41,530 square miles.6 The head of the basin is in the semiarid plains, from which there is practically no run-off. Above Ballinger the river has a drainage area of 16,840 square miles,8 of which it is estimated that about 11,500 square miles probably con­ tributes no flow. Below Ballinger the river drains a mountainous country until it reaches the Coastal Plain at Austin. Below Austin the basin becomes comparatively narrow and has a maximum width of only about 35 miles. The following table shows the altitude of the stream bed at various places and the average descent between those places from a point near San Saba to the mouth: TABLE 2. Altitude and average descent of the Colorado Riverfront a point near San Saba to the mouth

Altitude River dis­ Average de­ above mean tance above scent between Place of determination sea level mouth points (feet (feet) (miles) per mile)

1,096 449 1,000 417 3.0 960 405 3.3 800 373 5.0 Marble Falls...... _. _._ ._ _ ...... __ ... __ ... 700 356 5.9 590 331 4.4 500 300 2.9 422 264 2.1 270 191 2.1 Eagle Lake, gaging station near ______140 77 1.1 0 0 1.8

There was no flood of consequence on the Colorado River above the mouth of the Llano River when the Llano River flood of June 1935 reached the Colorado. The Pedernales River added its flow to the Colorado about halfway between the mouth of the Llano and Austin. The peaks from the two tributaries nearly joined in the Colorado. There was not much rain near or below Austin, and little flow was added below the mouth of the Pedernales. Gaging stations are maintained on the Colorado River at Ballinger, near San Saba, at Austin, at Smithville, and near Eagle Lake, all of which are equipped with water-stage recorders. At Austin and Smithville the recorders were submerged, but a reliable gage-height record was obtained at each station from a partial recorder-graph record, engineer's gage readings, United States Weather Bureau readings, and levels to high-water marks. A discharge measurement was made by current meter at Austin near the peak of the flood, and the maximum discharge was deter­ mined by a short extension of the rating curve. At Smithville the maximum discharge was computed by the slope-area method, using Kutter's formula. The maximum discharges of the Colorado River 8 Figures revised since publication In Water-Supply Paper 488, p. 29. GEOLOGICAL SURVEY WATEK-SUPPLY PAPEK 796 PLATE 56

}

A. SECOND SPAN OF ORIGINALLY 4-SPAN BRIDGE FALLING INTO RIVER.

B. LOOKING JUST DOWNSTREAM FROM BRIDGE; STEEL SPAN IN CENTER OF PICTURE BEING CARRIED DOWNSTREAM. LLANO RIVER AT LLANO AT ABOUT PEAK OF FLOOD OF JUNE 14, 1935. GEOLOGICAL SURVEY WATER-SUPPLY PAPER 796 PLATE 57

1

A. LLANO RIVER ON MASON-FREDERICKSBURG HIGHWAY.

B. NUECES RIVER ON UVALDE-LA PKYOR HIGHWAY. BRIDGES DESTROYED BY FLOOD OF JUNE 14, 1935. GEOLOGICAL SURVEY WATER-SUPPLY PAPER 796 PLATE 58 87° 9S°

^ Numbers refer to discharge measurement stations In tables 39 Numbers refer to precipitation stations in table 1

ISOHYETAL MAP OF THE MAJOR PART OF THE COLORADO AND NUECES RIVER BASINS AND PARTS OF ADJACENT RIVER BASINS. Shows rainfall, in inches, June 9-15, 1935. GEOLOGICAL SURVEY WATER-SUPPLY PAPER 796 PLATE

A. AT ABOUT PEAK OF FLOOD OF JUNE 15, 1935.

B. AT LOW WATER. CONGRESS AVENUE BRIDGE, COLORADO RIVER, AT AUSTIN. MAJOR TEXAS FLOODS OF 1935 241 near San Saba and near Eagle Lake were determined from well- defined rating curves. The maximum discharge for the station on the Pedernales River near Spicewood was obtained from a rating curve defined principally by slope-area measurements of previous floods. The mean daily discharges and the total run-off for the period of the June flood were computed for all river-measurement stations on the Colorado River below San Saba (see fig. 35), on the Llano River, and on the Pedernales River near Spicewood. These records are presented under "Stages and discharges" (pp. 258-266). At certain places in the Llano River Basin only the peak discharges were deter­ mined. Data on the Llano River are presented on pages 241-245. The maximum discharges at stations on the Colorado and Peder­ nales Rivers are summarized in table 3. This table also gives the effective drainage area and discharge per square mile for each item. TABLE 3. Maximum discharge at river-measurement stations on the Colorado and Pedernales Rivers, June 1935

Maximum discharge Drainage area No. on Stream (square Second- pi. 58 miles) Second feet per Time feet square mile

5...... Colorado River near San Saba ___ "18,800 June 15, 2:45 p. m ..... 71, 000 3.78 6...... « 26, 350 June 15, 3:45 p. m _ 481, 000 18.3 7...... « 27, 850 June 16, 4:30 p. m. .... 305, 000 11.0 8...... Colorado River near Eagle Lake.... « 29, 140 June 19, 2:30 a. m_. ... 177, 000 6.07 14...... Pedernales River near Spicewood... 1,294 105,000 81.1

« 11,800 square miles deducted for noncontributing area. Table 14 (p. 283) gives a summary of maximum discharges measured during the major floods of 1935; for comparison, the previous known maxima are given. Plates 59, A, and 60, A, show the Colorado River at Austin at about the peak of the flood. The peak stage at Austin in June 1935 is about 1 foot lower than the peak stage in July 1869, which was the highest stage known. Below Austin the flood of June 1935 was considerably lower than that of 1869. A record of previous high stages and discharges at Austin since the river-measurement station was established in 1898 is given in Water-Supply Paper 771, Floods in the United States, magnitude and frequency, page 335.

LI/ANO RIVER FLOOD The Llano River is formed by the confluence of the North Llano and South Llano Rivers at the town of Junction. These rivers have fco 500 bO

S i P p.

400 el Pa o

P 300

H O W

^ ED 4 o ct- p_i p_, fed I ' £j. CO O tO et- F Ol C Q O Q i_J * p Cfq P co 2 p - o" STr^ P< -

14 15 16 17 18 19 20 21 22 23 24

FIGURE 35. Hydrographs of discharge, Colorado River near San Saba, at Austin, at Smithville, and near Eagle Lake, June 11-24,1935. MAJOR TEXAS FLOODS OF 1935 243 Table 4 shows the altitude of the stream bed at various places on the North Llano, South Llano, and Llano Rivers from source to mouth and the average descent between those places. The altitudes and distances in the table were taken from topographic maps. TABLE 4. Altitude and average descent of the North Llano, South Llano, and Llano Rivers from source to mouth

Average de­ Altitude River dis­ scent be­ Place of determination above mean tance above tween points sea level mouth (feet per (feet) (miles) mile)

.North Llano River: 2,325 50.0 2,200 45.0 25.0 Do.. _ .... ___ ...... _ ...... _ .. 2,000 29.0 12.5 1,700 3.0 11.5 1,660 0 13.3 South Llano Eiver: 2,300 63.5 2,200 59.5 25.0 Do...... - __--.-. _. __ ..... 2,000 32.0 7.3 1,895 24.5 14.0 1,840 19.5 11.0 1,660 0 9.2 Llano River: Head. . . .. _ -...... __ ... 1,660 103.0 1,630 100.0 10.0 1,500 78.5 6.5 1,360 62.5 8.8 1,125 38.0 9.6 1,000 24.5 9.3 Do...... 850 .6.5 8.3 800 0 7.7

The June storm in the Llano River Basin was heaviest over the South Llano River, the Johnson Fork of the Llano River, and the upper reaches of the James River. (See fig. 36.) River-measurement stations are maintained on the North Llano River 3 miles northwest of Junction, on the Llano River 3% miles east of Junction, and on the Llano River 4K miles east of Castell. These stations are equipped with water-stage recorders, but the recorders at the two stations on the Llano River were submerged, and complete records of stage were not obtained. Gage-height .graphs were completed for these two stations on the basis of partial recorder graphs, levels to high-water marks, and local information. The maximum discharges were determined by the slope-area method, using Kutter's formula on the Llano River at the river- jneasurement stations near Junction and near Castell, on the South Llano River near Telegraph, about 24 miles above Junction, and on Paint Creek (tributary to the South Llano River about 19 miles above Junction) 1% miles above its mouth and near Telegraph. The mean daily discharges and the total run-off for the period of the flood were computed for river-measurement stations on the North Llano and Llano Rivers near Junction and on the Llano River near 'Castell. (See fig. 37.) These records are presented under "Stages 98P301 M Numbers refer to discharge measurement stations In tables 5 and 14 Op Numbers refer to precipitation stations in table 1

9S°30'

98P301

Isohyetal map of the Llano River Basin showing tributaries, places at which maximum discharges were determined, intermediate drainage areas, and total rainfall, in inches, for the period June 9-15,1935. MA JOE TEXAS FLOODS OF 1935 245 and discharges" (pp. 263-265). On the South Llano River and Paint Creek near Telegraph only the peak discharges were determined. The maximum discharges determined at various places in the Llano River Basin are summarized in table 5. This table also gives for each item the drainage area and discharge per square mile. TABLE 5. Maximum discharge determined at places in the Llano River Basin, June 1935

Maximum discharge No. on Drainage fig. 36 and Stream area Second- pi. 58 (square Second- feet per mile) Hour, June 14 feet square mile

9. North Llano River near Junction... 914 -47, 400 51.0 10..... _ . 1,762 319, 000 181 11...... 3,514 388, 000 110 12... ___ . South Llano River near Telegraph.. 540 160,000 296 13 __ ..... 218 69,300 318

"Discharge determined from poorly defined rating curve. The maximum discharges measured during the major floods of 1935 are summarized in table 14 (p. 283); for comparison, the previous known maxima are given. Plate 60, B, shows the South Llano River at Junction at about the peak of the flood on June 14, 1935. The floods of June 14, 1935, on the South Llano and Llano Rivers reached the highest stages ever known. At Junction the South Llano was 3 feet higher than in 1889, and according to local informa­ tion the 1889 flood was the highest known theretofore. The previous highest stage on the Llano River near Junction since the river- measurement station was established in 1915 was 27.15 feet on Sep­ tember 1, 1932, which may be compared with a stage of 43.3 feet in June 1935. The peak discharge of the flood of September 1932 was 106,000 second-feet. At the river-measurement station on the Llano River near Castell the highest stage known prior to June 1935 was in 1889, when a stage of about 28.4 feet was reached, according to local information, which may be compared with a stage of 37.0 feet in June 1935. The highest stage prior to 1935 since the river-measurement station was estab­ lished in 1923 was 22.3 feet on October 6, 1930, when there was a discharge of 89,800 second-feet.

NUECES RIVER BASIN NUECES RIVER FLOOD The Nueces River rises in the central part of Edwards County at an altitude of about 2,400 feet, flows south for about 100 miles and east for about 240 miles, and enters the Gulf of Mexico through 246 CONTKIBUTIONS TO HYDKOLOGY, 1937

Llano River near Castell, Tex

I /Llano River near Junction, Tex.

FIGURE 37. Hydrographs of discharge, North Llano River near Junction, Llano River near Junction, and Llano River near Castell, June 14-17,1935. MAJOR TEXAS FLOODS OF 1935 247 Corpus Christi Bay. The total drainage area is 16,950 square miles. The river flows for about 60 miles across the Edwards Plateau and enters the Coastal Plain about 10 miles northwest of Uvalde. Above Uvalde the river traverses a mountainous country having steep slopes and quick run-off from rainstorms. The country is largely covered by cedar and is utilized principally for ranching. The altitude of the stream bed at various places and the average descent between those places from a point 338 miles above to the mouth of the Nueces River are given in table 6. The data given were compiled from topographic maps. TABLE 6. Altitude and average descent of the Nueces River from source to mouth

Average Altitude River descent Place of determination above mean distance between sea level above mouth points (feet (feet) (miles) per mile)

2,325 338.0 Do... . ._ 2,300 337.8 125.0 Do...... 2,200 336.9 111.1 Do...... _ ...... 2,100 334.7 45.5 Do ...... 2,000 333.3 71.4 Do...... 1,800 328.8 44.5 Do...... _...... 1,600 315.5 15.0 Pulliam Creek, mouth _____ ...... 1,450 305.5 15.0 1,248 293.3 16.6 1,125 285.8 16.4 West Nueces River, mouth...... 955 272.8 13.1 Contour crossing ______900 268.2 12.0 860 263.0 7.7 800 256.3 9.0 376 169.0 4.9 Three Rivers, gaging station ______101 77.0 3.0 0 0 1.3

Gaging stations are maintained on the Nueces River at Laguna, near Uvalde, at Cotulla, and near Three Rivers. The concrete gage well at the station near Uvalde was destroyed, and the gage-height record was lost. A gage-height graph for this station was reproduced from a partial recorder chart, readings of stage at a railroad bridge 4.7 miles upstream, and information obtained from local residents. The recorder instrument at Cotulla was removed to avoid submergence; a gage-height graph was drawn on the basis of readings of a staff gage and levels to the high-water mark. The peak discharge was determined by the slope-area method, using Kutter's formula, at Laguna, near Uvalde, and at Cotulla; the peak discharge near Three Rivers was determined from a short extension of the rating curve. The largest flood came from the West Nueces River, which enters the Nueces River between Laguna and Uvalde. (See fig. 38.) The mean daily discharges and the total run-off for the period of the flood were computed for all river-measurement stations on the Nueces River. These records are presented under "Stages and dis­ charges." 700

600

500

,. Hueoes River near Uvalde, Tex. o 400

300

200 i TV

. Hueces River at Laguna, Tex.

100 Nueces River at Cotulla, Tex. * -- .BUCUCONueces RiverCIJ.VC.C atc&u ThreeXJ1X1SC Rivers,

14 15 16 17 18 19 20 21 22 23 24' 25 26 27 June FIGURE 38. Hydrographs of discharge, Nueces River at Laguna, near Uvalde, at Cotulla, and near Three Rivers, June 14-27,1936. GEOLOGICAL SURVEY WATER-SUPPLY PAPER 796 PLATE 60

A. COLORADO RIVER AT AUSTIN, LOOKING NORTH ON CONGRESS AVENUE FROM RIGHT BANK AT ABOUT PEAK OF FLOOD OF JLNE 15, 1935.

B. SOUTH LLANO RIVER AT JUNCTION, NEAR PEAK OF FLOOD OF JUNE 14, 1935. GEOLOGICAL SURVEY WATER-SUPPLY PAPER 7C6 PLATE 61

A. VIE\S FROM LFFT BANK AT ABOUT 10 FEET BELOW PEAK STAGE ON JUNE 14. 1935.

B. VIEW FROM RIGHT BANK ABOUT 30 MINUTES BEFORE BRIDGES WERE DESTROYED. Water went over and removed highway embankment on opposite bank. The remains of bridges after flood had passed are shown on plate 57, B. NUECES RIVER ON UVALDE-LA PRYOR HIGHWAY. GEOLOGICAL SURVEY WATER-SUPPLY PAPER 796 PLATE 62

A. LOOKING UPSTREAM FROM JUST BELOW LOWER CROSS SECTION.

B. LOOKING TOWARD RIGHT BANK AND UPSTREAM FROM ABOUT LOWER CROSS SECTION. WEST NUECES RIVER NEAR BRACKETTVILLE. Slope reach used in determining discharge for flood of June 14,1935. (See also fi?. 40.) MAJOR TEXAS FLOODS OF 1935 249 The maximum discharges determined at stations on the Nueces River are given in table 7, also the drainage area and discharge per square mile. (See also table 14, p. 283.)

TABLE 7. Maximum discharges at river-measurement stations on the Nueces River for the flood of June 1935

Maximum discharge Drain­ No. on pi. age area 58 Location (square Second- miles) Second- feet per Time feet square mile

18... _ ... 764 June 14, 11 a. m ...... 213, 000 279 19...... 1,930 June 14, 4 p. m._ ...... 616 000 319 on 5,260 82, 600 15.7 91 15, 600 66,700 4.28 Do. __ -. . -... 15, 600 June 23, 7 p. m "...... 56, 000 3.59

« Probably same peak as at other stations. Plates 57, B, and 61, A, B, show views of the Nueces Kiver between Uvalde and La Pryor at about 10 feet below the peak stage on June 14, 1935. A stage of about 29 feet occurred at Laguna in June 1913, which is the maximum known at that place. The stage in June 1935 was 26.0 feet. The flood of September 1923 reached a stage of 26.5 feet, and the flood of 1903 reached a slightly higher stage. The highest stage known at Uvalde previous to the stage of 36.9 feet in June 1935 was 26.4 feet in June 1913. A section was cut from a pecan tree washed down in June 1935, and by counting the annual growth rings this tree was found to be 115 years old. It is inferred from the position of the tree in relation to the river channel that the period elapsed since the occurrence of a flood of magnitude similar to that of 1935 must have exceeded the life of the tree. The highest stage recorded at Cotulla prior to 1935 was 26.8 feet, September 7, 1932. A stage of 29.7 feet is reported to have occurred in June 1889. The stage in June 1935 was 32.4 feet. The highest stage known at Three Kivers was 46.0 feet, September 18, 1919, with a discharge of 85,000 second-feet determined from an extension of the rating curve. The maximum stage in June 1935 was 44.67 feet. WEST NUECES RIVER FLOOD The West Nueces River rises in the central part of Edwards County, flows south and southeast about 100 miles, and enters the Nueces River at the edge of the Edwards Plateau about 10 miles northwest of Uvalde. The drainage basin has an area of 923 square miles, is rough and rocky with steep slopes, extensively covered with cedar, and is utilized largely for ranching. 58805 39 3 250 CONTRIBUTIONS TO HYDKOLOGY, 1937

The altitude of the stream bed at various places and the average descent between those places are given in table 8. The data pre­ sented were compiled from topographic maps. TABLE 8. Altitude and average descent of the West Nueces River from source to mouth

Altitude River dis­ Descent be­ above mean tance above tween points Place of determination sea level mouth (feet per (feet) (miles) mile)

Contour crossing ___ ,. ______2,300 101.0 Do.... 2,250 100.0 60.0 Do...... -....-,...... 2,200 97.3 Do...... 2,150 94.3 16.7 Do...... 2,100 91.5 17.9 Do.. . . _ . _.. ___ 2,000 89.2 43.5 Do...... __. 1,900 85.0 23.8 Do...... 1,800 78.8 16.1 Do.., . -...... 1,700 73.1 17.5 70.5 Contour crossing... ______1,650 68.1 10.0 Do... ._...... 1,550 60.5 13.2 Do...... 1,400 44.5 9.4 Do...... -. _. 1,300 38.1 15.6 Do...... _. . __ 1,200 24.2 7.2 Do- .---- 1,100 14.5 10.3 Cline, measuring section 8 miles above __ . ______13.0 1,050 9.7 10.4 Do. _ _ ...... 1,000 3.8 8.5 055 0 11.8

The heaviest rain of the June storm fell over the upper part of the West Nueces River Basin, and most of the flood in the Nueces River came from this tributary. (See fig. 39.) There are no river-measurement stations on the West Nueces River, and no data from which the run-off could be computed were available. The peak discharge was determined 28 miles above Brackettville and 8 miles above Cline by the slope-area method, using the Manning and Kutter formulas, respectively. The peak discharge near Brackett­ ville was computed as 580,000 second-feet from an area of 402 square miles, or a discharge of 1,440 second-feet per square mile. The peak discharge near Cline was computed as 536,000 second-feet from an area of 880 square miles, or 609 second-feet per square mile. The drainage areas were measured from topographic maps published by the Geological Survey of the United States Department of the Interior and the Corps of Engineers, U. S. Army. A very small part of the drainage area not shown on these sheets was determined from a county road map and a Geological Survey map of Texas on the scale of 1:500,000. The flood of June 1935 was the greatest ever known on the West Nueces River, according to statements of ranchmen who have been living near the stream for many years. No one could be found who had ever heard of a flood that was comparable in extreme magnitude with this one. MAJOR TEXAS FLOODS OF 1935 251

30°00'

Numbers refer to discharge measurement stations in

Numbers refer to precipitation stations in table 1

ioo°oo' 29°sa'

.Brackeltville

0Cline wo-oo1 O 2 4 6 6 10 MILES

FIGURE 39. Isohyetal map of the West Nueces Eiver Basin showing discharge measuring places, inter­ mediate drainage areas, and total rainfall, in inches, June 9-15,1935, as estimated from somewhat meager information. 252 CONTRIBUTIONS TO HYDROLOGY, 1937

DETERMINATION OF DISCHARGE NEAR BRACKETTVHIE The computed maximum discharge per square mile of drainage area of the West Nueces River 28 miles above Brackettville exceeds any rates known previously for areas of similar size. A thorough investigation and survey was made in the field, and the field data were carefully analyzed. Because of the unparalleled features of the result, some descriptive details as to its determination are given below. Figure 40 shows the plotting of observed high-water marks, the adopted slope lines, and the cross sections used to determine the maximum discharge. Plate 62 shows views of the slope reach. All computations are summarized in table 9. TABLE 9. Computations for slope-area determination of discharge, West Nueces River near Brackettville, June 14, 1935 [For meaning of symbols see p. 230] Determination of discharge unconnected for velocity head

Area 1.486 Discharge Cross section (square w. p. r rvs s S»/2 n V (second- feet) n feet)

A...... 26, 222 746 35.15 10.73 0.00305 0. 05S2 0.030 49.5 29.3 770, 000 B...... 25, 119 720 34.89 10.68 . 0030S .0552 .030 49.5 29.2 733, 000 Average discharge uncorrected for v< locity he ad 751,500

Correction for velocity head

T/2 [Assume discharge of 580,000 second-feet; velocity head=-g- (g= acceleration of gravity)]

Cross section V ^ (feet) Correction to slope Corrected slope

A...... -.... .-.. .- 580,000 nn (22. 1)> 26, 222 ""' 64. 3 7< 6l 7. 61-8. 31 S, =0.00305 568 (length of reach) -. 001233 B. .. .._ .. ... 580,000 , , 25, 11 ~"d- 1 64. 3 S- "* = -0.001233 =.001817

[Recompute discharge using corrected slope]

Area 1.486 Discharge Cross section (square w. p. r r'/» c «l/8 n V (second- feet) n feet)

A...... 26,222 746 35.15 10.73 0.001817 0.0427 0.030 49.5 22V6 593, 000 B...... 25, 119 720 34.89 10.68 .001817 .0427 .030 49.5 22.5 566, 000 Average discharge to three signiflcar t figures 580,000

The discharge as recomputed, using slope corrected for velocity head, checks the assumed discharge; therefore the adopted discharge is 580,000 second-feet. The factors considered in selecting this site for a slope-area deter­ mination of discharge and other pertinent information concerning it are as follows: (1) The channel was straight for about 1 mile above 100 200 300 400 500 600 700 800 900' 1,000 1,100 1,200 1,300 Feet along center of channel Profiles of high-water marks 60 Water surface

30

Wa1;er surface

30

Section B

50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 Distance in feet from left edge of high water fcO FIGUEB 40. Profiles of high-water marks and sections]of slope-area reach on the West Nueces River near Brackettville. Oi 00 254 CONTRIBUTIONS TO HYDKOLOGY, 1937

the reach and for about 500 feet below, where it bends slightly to the right. (2) All flow was in one channel about 712 feet wide and with depths ranging from about 33 feet near the left bank to about 45 feet near the right bank. (3) Cross sections were measured 568 feet apart; the altitudes of the high-water marks on the right bank were determined from a point about 200 feet above the upper cross section to a point about 300 feet below the lower cross section without a noticeable break in the slope. (4) The sides of the channel were of solid rock and could not have changed during the flood; the bed was of gravel, showed no evidence of appreciable shifting, and, ac­ cording to statements of local residents, appeared to be in the same condition after the flood as before except for filling in of a pool on the right side of the channel to a depth of 1 or 2 feet. (5) The channel was free of vegetation except for light brush along the higher part of both banks. (6) The area of the lower cross section was 4 percent smaller than that of the upper cross section; the distribution of the change was apparently uniform. (7) The high-water marks on the left bank were very well defined and were well distributed over the reach. Those on the right bank were not so well distributed, but well-defined marks found above and below the reach aided in defining the slope of the water surface. (8) The channel above and below the measuring section is clean and open and offers no obstruction to the approach or get-away of the stream. (9) No evidence of any movement of debris was apparent except the small amount of gravel mentioned above (4), either at the measuring section or for several miles above and below. However, with mean velocities hi excess of 20 feet a second (see table 9) and the material of gravel as indicated in plate 62, it seems possible that there may have been bed move­ ment. (10) The slope of the bed through the reach was uniform, and there was no adverse slope either within or immediately adjacent to the reach. High-water marks indicated that the water surface was about 3 feet higher on the right bank than on the left bank. The deeper part of the channel is near the right bank. The association of the higher marks with the deeper channel is consistent with a study of many slope-area measurements made in Texas, in which it has been found that if the water surface is not level in a channel cross section it is usually higher on a side where the channel is deeper and the velocity of flow presumably greater than elsewhere in the channel. The selection of the value of 7i=0.030, the coefficient of roughness used in the application of Manning's formula, was made in the light of experience in the determination of n in measurements of the dis­ charge of Texas streams, where rating curves based on slope-area determinations of discharge have been satisfactorily checked later by current-meter measurements. The value of n selected is consistent MA JOE TEXAS FLOODS OF 1935 255 with values used for other slope-area measurement reaches in Texas and in other parts of the United States. Studies of n have been made on the Brazos and Colorado Rivers for discharges up to 481,000 second-feet. Many of the n's computed from measured discharges on these streams in reaches with apparently rougher beds than in the reach on the West Nueces River near Brackettville have been less than 0.030. The altitudes of the high-water points were averaged in groups, and the slope line was drawn through the mean position of the points so determined. Upper enveloping lines of the points plotted in figure 40 indicate slopes substantially parallel to those drawn. The discharge was computed in table 9, using each cross section as a single channel. For comparison and check the discharge was computed by dividing the cross sections into several parts having different hydraulic radii and coefficients of roughness; the results of this determination gave discharges within a small percentage of the discharge as originally determined. A computation of discharge was also made using only the left-bank slope, which was the natter and lower of the slopes defined by the high- water marks on the two banks. This condition seems to conform to the flattest slope and the smallest cross-sectional area of the channel that could be selected. The discharge so computed was 537,000 second-feet, which is seemingly near the minimum result that coiild be obtained from the base data. This method ignores the observa­ tions made on the right bank, which when taken into account produced the adopted discharge. A reconnaissance was made of the West Nueces River from its headwaters to a point several miles below the slope-area reach. At no place was evidence found that would suggest that the flood peak was a momentary wave due to the release of a channel obstruction, or to any other cause. No section above was found where it would have been possible for the channel to be blocked. The computed mean velocity of about 22.5 feet a second is a rate of travel of slightly more than 15 miles an hour. Had the peak re­ mained stationary for only 15 minutes it would have filled a length of channel of 3.8 miles. Local residents stated that they believed the river remained at maximum stage for as long as 30 minutes. This condition would seem to have led to the establishment of reasonably steady flow and hence to preclude the possibility that the high-water marks were produced by a sharp momentary wave. The result of 580,000 second-fee t was obtained by the application of the Chezy and Manning formulas in a slope-area determination. The result is naturally subject to such limitations of accuracy as are involved in the application of these formulas to a combination of conditions more or less outside the range of ordinary experience. It 256 CONTRIBUTIONS TO HYDROLOGY, 1937 ignores any effect of the expenditure of the energy of flow in the move­ ment of sUt and gravel as bed load and assumes that the section of channel was the same during the time of peak discharge as after the flood, when the survey was made. As indicated in the above discus­ sion, this procedure seemed justified by the available evidence. However, such uncertainties must be kept in mind in any compari­ son of the discharge with those obtained on other streams by more accurate methods, and any user of the data is cautioned to remember the method of derivation and, if thought desirable, to make such allowance therefor as may seem appropriate.

FRIO RIVER FLOOD The Frio River rises in Real County about 20 miles east of the Nueces River and flows roughly parallel to the Nueces throughout its length. The Frio did not go as high in 1935 as in 1932, when the maximum known flood occurred. The Dry Frio River, tributary to the Frio, was higher than ever known before. The Dry Frio River rises in central Real County and flows south about 40 miles (air-line distance) to its confluence with the Frio River near Knippa. It traverses a rocky, hilly region, about 250 square miles in area, from 1,000 to 2,000 feet in altitude, and covered by cedar and oak trees. Its drainage basin is adjacent to that of the Nueces River. A slope-area measurement was made on the Dry Frio River 4 miles below Reagan Wells for determining the maximum discharge. The discharge as computed by Kutter's formula was 64,700 second-feet, which is equivalent to 539 second-feet per square mile for the drainage area of 120 square miles. The maximum previous flood of which there is reliable information occurred in July 1932 and reached a stage at Reagan Wells about 3.0 feet lower than the 1935 flood. The peak discharge of the 1932 flood as determined by the slope-area method at a section 2.6 miles below Reagan Wells was 30,700 second-feet. No river-measurement station is maintained on the Dry Frio River, but records of flow during the flood at the river-measurement stations on the Frio River at Concan, near Derby, at Cotulla, and at Calliham, are presented under "Stages and discharges" (pp. 273-276).

ATASCOSA RIVER FLOOD The Atascosa River rises in the northern part of Atascosa County and flows east and south about 80 miles to its confluence with the Frio River near the town of Three Rivers. The drainage basin lies entirely within the Coastal Plain and is utilized to a great extent for farming. MAJOK TEXAS FLOODS OF 1935 257

The highest stage known occurred at the river-measurement station at Whitsett on June 14. The peak discharge of 38,300 second-feet was determined by the slope-area method. A station description and a table of mean daily discharges and the total run-off for the period of the flood are presented under "Stages and discharges" (pp. 258-276).

BIO GRANDE BASIN From 8 to more than 18 inches of rain fell over the Sycamore Creek Basin, which lies to the west and adjacent to the Nueces River Basin, during the period June 9-15, causing the greatest flood known. High but not record-breaking floods occurred in adjacent basins. Data per­ taining to the floods in the Rio Grande Basin may be found in Water Bulletin 5 of the International Boundary Commission, United States and Mexico. This organization maintains several river-measurement stations on the Rio Grande and its tributaries. The stations mostly affected by the June floods are those on San Felipe, Sycamore, and Pinto Creeks near Del Rio. The difference in flow past discharge- measurement stations on the Rio Grande at Del Rio and at Eagle Pass will indicate the run-off from the area receiving the intense pre­ cipitation. The maximum discharges past the river-measurement stations men­ tioned above are shown in table 14 (p. 283). All figures are taken from Water Bulletin 5, above noted.

STAGES AND DISCHARGES OF MAY AND JUNE FLOODS On the following pages are presented stage and discharge records at the river-measurement stations experiencing unusual floods as above discussed. These records consist essentially of a station description, a table of mean daily discharges and the total run-off for the flood periods, and a table of discharges at indicated times during the floods in sufficient detail for reasonably reliable delineation of hydrographs. The last-mentioned table may be used to determine the rating curve for the station provided account is taken of the limits to which gage heights were applied, as given in the "Gage-height record" paragraph of the station description, and of periods when the shifting-control method of determining discharge was used. For some river-measure­ ment stations on streams adjacent to those experiencing unusual floods there are given records of mean daily discharges and the total run-off for the flood period. In the "Drainage area" paragraph of the station description for some stations the probable noncontributing area is noted. This is the area that lies above the Cap Rock and is believed never to con­ tribute any surface run-off to the lower reaches of the streams. The 258 CONTKIBUTIONS TO HYDKOLOGY, 1937 drainage areas were measured from such topographic maps as were available and from soil maps and county road maps. The paragraph "Maxima" in the station description is divided into three subparagraphs. The first subparagraph, headed "1935," gives the maximum discharge and gage height occurring during the floods of June 1935. The second subparagraph, headed by the inclusive dates of systematic records, gives the maximum gage height and the corresponding discharge, if determined, during the period of systematic records prior to September 30, 1934. The third subparagraph, headed by the inclusive dates, gives the maximum stage and discharge, if de­ termined, during the period prior to the beginning of systematic records. The information in this third subparagraph is based mostly on information from local residents and is of varying degrees of accu­ racy and reliability.

COLORADO RIVER NEAR SAW SABA, TEX. LOCATION. Lat. 31° 13', long. 98°34', at Red Bluff Crossing, 5.7 miles below confluence with San Saba River and 9.2 miles east of San Saba, San Saba County. Zero of gage is 1,096.22 feet above mean sea level. DRAINAGE AREA. 30,600 square miles, of which about 11,800 square miles is probably noncontributing. GAGE-HEIGHT RECORD. Water-stage recorder graph. Gage heights used to half tenths between 3.9 and 6.8 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 120,000 second-feet. MAXIMA. 1935: Discharge for flood period, 71,000 second-feet 2:45 p. m. June 15 (gage height, 38.50 feet). Discharge for year, 86,000 second-feet May 19 (gage height, 41.00 feet). 1916-34: Discharge, 163,000 second-feet Apr. 26, 1922 (gage height, about 54 feet, present site and datum). 1900-1915: Discharge, 184,000 second-feet Sept. 25, 1900 (gage height, about 57.5 feet, present site and datum). REMARKS. Small diversions above station for irrigation and municipal supply affect low flow only. Mean discharge, in second-feet, and run-off, in acre-feet, June 19S5

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

11 _ .... 1,960 3,890 16 64,100 107, 300 21 2,410 4,780 26 2,160 4,280 12...... 1,760 3,490 17 39,200 77, 750 22 2,250 4,460 27 2,600 5,160 13 _ .... 2,860 5,670 18 14, 400 28, 560 23 1,920 3,810 28 3,440 6,820 14. _ ... 5,630 11, 170 19 5,500 10, 910 24 1,410 2,800 29 1,490 2,960 15...... 54,600 108, 300 20 3,400 6,740 25 2,250 4,460 30 1,210 2,400 Ru i-off, in £ cre-feet, or perioc June 11--30 405, 700 MAJOR TEXAS FLOODS OF 1935 259

Gage-height, in feet, and discharge, in second-feet, at indicated time, 1935

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June 10 June 15 Con. June SI 12 midnight.... 5.67 2,160 36.40 62,500 6 a. m ...... 5.76 2,250 37.90 68, 100 9 -_ .__...- 5.67 2,160 June 11 38.40 70, 500 12 noon ____ 5.80 2,250 38.50 71, 000 6 p. m ...... 6.25 2,580 5.42 1,920 38.50 71, 000 9 _ ...... 6.36 2,790 4... ___ ...... 38.40 70,500 12 midnight .... 6.40 2,790 June 12 5...... 38.20 69, 500 7 ...... 37.60 66,900 June SS 3a.m. ____ 5.15 1,720 9.-...... 36.90 64,200 3 a. m ...... 6.28 2,680 5.28 1,840 12 midnight _ . 36.00 61,200 9...... 5.84 2,250 12 noon. ___ 5.25 1,800 5.65 2,080 12 midnight .... 5.16 1,720 June 16 5.55 2,040 June IS 35.20 59, 000 12 midnight .... 5.47 1,960 6 ...... 34.30 56,800 June SS 5.14 1,720 32.80 53,500 5.20 1,760 12 midnight. ... 30.10 48,000 5.44 1,960 5... ____ ..... 6.30 2,680 5.42 1,920 6... __ . __ .. 7.25 3,800 June 17 5.30 1,840 9...... 8,60 6,230 11.. _ . _ . .... 8.85 6,600 28.30 44,400 June 24 25.90 39, 600 June 14 23.00 33,800 4a.m...... 4.90 1,520 12 midnight .... 20.10 28,100 8 ... 4.79 1,450 la. m...... 8.65 6,230 12 midnight .... 4.70 1,380 4...... 7.90 4,960 June 18 7...... 7.40 4,110 June IS 12 noon...... 7.16 3,800 6 a. m ...... 15.60 19,200 4.95 1,560 Ip. m ...... 7.32 3,950 12 noon...... 12.00 12,400 5.40 1,920 2...... 7.90 4,960 6 p. m _ ...... 10.07 8,960 6.00 2,410 4 _____ ..... 8.95 6,960 12 midnight .... 8.92 6,780 6.05 2,410 8...... 9.23 7,320 6.00 2,410 11.. _ ...... 9.28 7,510 June 19 12 midnight .... 5.74 2,160 12 midnight .... 9.42 7,690 8.18 5,500 June 86 June IB 12 midnight.... 7.45 4,110 5.50 2,000 15.00 18,000 June iO 12noon_._ ..... 5.55 2,040 2 17.00 22,000 5.80 2,250 4 ____ ...... 20.50 28,900 6.90 3,370 7.. ___ ... . 5.87 2,330 6 ____ . __ ... 28.20 44, 200 6.72 3,120 9.... _ . _ . 6.13 2,500 8...... 34.20 56, 600 12 midnight _ . 6.35 2,790 12 midnight.... 5.75 2,250

COLORADO BIVEK AT AUSTIN, TEX. LOCATION. Lat. 30°16', long. 97°45', at Congress Avenue viaduct in Austin, Travis County. Zero of gage is 421.86 feet above mean sea level. DRAINAGE AREA. 38,150 square miles, of which about 11,800 square miles is probably noncontributing. GAGE-HEIGHT RECOBD. Water-stage recorder graph or graph drawn from fre­ quent gage readings. Gage heights used to half tenths between 1.4 and 3.6 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements. MAXIMA. 1935: Discharge, 481,000 second-feet 3:45 p.m. June 15 (gage height, 41.2 feet from floodmarks on gage structures at bridge pier; 42.0 feet to same datum from U. S. Weather Bureau gage on bridge at center of first span from left bank). 1898-1934: Discharge, about 236,000 second-feet a few minutes after failure of Austin Dam Apr. 7, 1900 (gage height, 33.5 feet). At time of failure, depth of water over dam was 11.07 feet (computed discharge, 151,000 second-feet); flood appeared to be practically at its crest when dam failed. 1843-97: Stage, about 43 feet July 7, 1869 (discharge not determined). Remarks. Low flow partly regulated by diversions and reservoirs upstream. 260 CONTKIBTJTIONS TO HYDKOLOGY, 1937

Mean discharge, in second-feet, and run-off, in acre-feet, June 1935

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

12..... 4,970 9,860 17 81, 200 161, 100 22.... 10, 300 20,430 27 . 5,050 10,020 13..... 8,840 17, 530 18.... 57, 500 114, 000 23. _ 17, 200 34, 120 28 5,050 10, 020 14 13, 700 27, 170 19.... 32, 400 64,260 24 10,300 20, 430 29 5,660 11,230 15..... 323, 000 640, 700 20 17,900 35, 500 25 7,880 15, 630 30 . 6,600 13, 090 16. . 143, 000 283,600 21 13,000 25, 790 26. _ 5,660 11,230 Bun-oft,lniware-feet, fc>r period June 12-3g 1,526,000

Gage-height, in feet, and discharge, in second-feet, at indicated time, 1985

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June 11 June 15 Cont. June 11 12 midnight.... 2.40 5,480 5 p. m ...... 40.9 470, 000 4.37 13,000 6 ...... 40.3 449, 000 12 midnight .... 3.78 11, 000 June It 9...... 37.5 354, 000 12 midnight _ 34.6 276, 000 June SS 2.20 4,800 12 midnight .... 2.23 4,970 3.37 9,990 3.20 9,330 June IS 3 a m ...... 31.6 215, 000 10. 4.00 12,000 6..... ___ . _ . 28.3 170, 000 2.42 5,480 9...... oc 7 143, 000 12 noon ...... 2.90 7,200 23.7 124, 000 3.90 10,800 99 d 113,000 4.84 15, 300 6 __ ...... 4.76 14, 400 6 ____ ...... 91 ^ 105, 000 4 ______. _ . 5.30 17, 300 7...... 4.76 14, 400 9 __ ...... 20.55 100, 000 7 ___ ...... 5.93 19,900 10...... 4.66 14,000 1 n o 95,900 8 ...... 6.05 20,300 9 __ ...... 6.11 20,800 10 .. 6.09 20,800 11 .. _ .... 6.00 20,300 4 a. m_____ 4.30 12, 400 1Q A 01 ann 5.85 19,500 12 noon ...... 3.69 10, 100 17.2 80, 600 4.75 15, 300 3.60 9,700 16.0 73, 500 12 midnight. 4.08 12,700 6 ______. 3.70 10, 100 15.0 68,200 9..... __ ...... 3.85 10, 800 10 .... __ . 4.80 14, 400 11 ______.. 10.70 45, 700 3.76 11,700 12 midnight _ . 14.30 64, 600 6 a. m ...... 14.1 63, 400 3.02 9,000 12 noon ...... 13.1 57, 500 12 midnight .... 2.80 8,360 June IB 12.15 61, 600 12 midnight .... 11.02 45, 200 June S5 la.m...... 16.50 76, 400 2_____ . __ . 19.00 95, 300 2.60 8,040 3...... 24.00 128, 000 12 midnight- ... 2.13 6,600 4. __ .. 27.1 157, 000 9.85 38, 700 5 ______. 30.0 191, 000 8.62 qi Af\n 6 ______. 31.8 219, 000 25, 800 8...... 36.3 319, 000 12 midnight .... 6.65 22, 100 1.83 5,660 9 ____ . _ .... 38.2 377, 000 12 midnight .... 1.62 4,900 10...... 38.9 400, 000 11 __ . ____ . 39.1 406, 000 12 noon...... 39.8 431, 000 6.03 19, 000 40.8 467, 000 17, 300 3 ____ ...... 41.1 478, 000 5.35 16, 100 4-...... -... 41.2 481, 000 5.10 15, 300

NOTE. Discharge determined by shifting-control method except from 2 a. m. June 15 to 9 a. m. June 16. COLORADO RIVER AT SMTTHVHLE, TEX. LOCATION. Lat. 30°01/, long. 97°10', 1,200 feet above highway bridge at Smith- ville, Bastrop County. Zero of gage, 270.14 feet above mean sea level; DRAINAGE AREA. 39,650 square miles, of which about 11,800 square miles is probably noncontributing. GAGE-HEIGHT RECORD. Water-stage recorder graph except for short time on June 16 when recorder was submerged and graph was drawn from gage readings MAJOK TEXAS FLOODS OF 1935 261

and record of peak stage. Gage heights used to half tenths between 2.9 and 5.2 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 148,000 second-feet; extended to peak stage on basis of one slope-area meas­ urement of that peak. MAXIMA. 1935: Discharge, 305,000 second-feet 4:30 p. m. June 16 (gage height, 42.5 feet, from floodmarks). 1930-34: Discharge, 67,500 second-feet Oct. 9, 19, 1930 (gage height, 21.40 feet). 1913-29: Stage, about 47.4 feet December 1913 (discharge not determined). REMARKS. Low flow partly regulated by diversions and reservoirs upstream.

Mean discharge, in second-feet, and run-off, in acre-feet, June 1935

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

12...... 5,940 11, 780 17 184, 000 365, 000 22 13,300 26,380 27 6,260 12,420 13...... 7,860 15, 590 18 101,000 200,300 23 12,000 23,800 28 5,770 11,440 14...... 17,800 35, 310 19 60,500 120,000 24 15,200 30, 150 29 5,610 11, 130 15...... 29,000 57,520 20 28,400 56, 330 25 9,560 18, 960 30 6,090 12,080 16-.. 219, 000 434,400 21 17,400 34, 510 26 7,630 15, 130 Rtm-off, in £icre-feet, f<>r periocI June 12-30 1,492,000

Gage-height, in feet, and discharge, in second-feet, at indicated time, 1935

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June 11 June IB Con. June SO 8.14 7,110 17.8 40,400 14.5 27, 000 6..... _ ...... 18.3 43, 000 12 7 20,800 7...... _ ... 19.5 49, 500 8.. ____ . .... 20.2 53. 500 7.40 5,770 9.. ___ ...... 21.1 58,800 7.35 5,610 10...... 22.3 66, 100 12 4 19, 600 7.17 5,450 12 midnight .... 24.4 80, 000 11.6 17,200 12 midnight .... 10.8 14,600 June IS June 16 June 88 6.97 5,150 27.6 104, 000 10 ...... 7.00 5,150 6... ___ ...... 32.7 148, 000 10.35 13, 300 7.30 5,610 9...... 37.2 203, 000 10.00 12,200 8.40 7,630 40.2 254, 000 4...... _ ...... 10.00 11, 500 2 p. m ...... 41.6 284, 000 June US 6.. ____ ...... 10.40 12, 500 3 __ . ____ 42.1 295, 000 8...... _ 10.25 12,000 4...... 42.5 305, 000 12 noon ...... 9.30 10, 500 10..... _ 9.95 11, 500 5...... 42.4 303, 000 9.80 11, 700 9.83 11, 000 6...... 42. 1 295, 000 11.40 16,000 9...... 41.3 277,000 June 14 12 midnight- ... 40.3 256,000 June 84 10.13 12,000 11.85 17, 800 4...... _ .. ... 10.90 14, 000 6. _____ .. ... 11.96 18,100 8_...... 12. 35 18, 700 38.1 217,000 9...... 11.73 17 ^fift 13.05 20, 500 35.5 180, 000 11.30 16, 000 13.15 21. 100 32.7 148, 000 10.40 10 Of-lfl 4. ___ ..... _ 13.00 20,800 12 midnight .... 30.4 126, OCO 12 midnight. ... 9.87 12, 000 8.. _ ..... _ .. 12.20 18, 100 12 midnight .... 11.20 15, 100 June 18 June 25 6 a. m _____ 28.6 112, 000 9.02 9,560 27.3 102, 000 12 midnight. ... 8.43 Q 9K(\ 9.80 11, 000 6 p. m ...... 25.8 91, 300 11..... ___ ... 10.00 11, 500 12 midnight .. 24.1 80, 000 June 86 10.50 12,700 12.2 17, 800 8.12 7,810 2.. _ ...... 15.0 27,800 12 midnight .... 7.65 6,940 3... ____ . .... 16.4 33,900 21.0 60,600 4... ___ ...... 17.2 37,800 12 midnight .... 17.5 40,900

NOTE. Discharge determined by shifting.control method except June 16-20. 262 CONTKIBUTIONS TO HYDKOLOGY, 1937

COLORADO RIVER WEAR EAGLE LAKE, TEX. LOCATION. Lat. 29°35', long. 96°25', at Lakeside Irrigation Co.'s pumping plant, 5 miles southwest of Eagle Lake, Colorado County. Zero of gage is 139.56 feet above mean sea level. DRAINAGE AREA. 40,940 square miles, of which about 11,800 square miles is probably noncontributing. GAGE-HEIGHT RECORD. Water-stage recorder graph. Gage heights used to half tenths between 2.7 and 5.5 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements. MAXIMA. 1935: Discharge, 177,000 second-feet 2:30 a. m. June 19 (gage height, 29.45 feet). 1930-34: Discharge, 57,500 second-feet Oct. 21, 1930 (gage height, 20.48 feet). 1913-29: Stage, about 32.0 feet December 1913, present site and datum (discharge not determined). REMARKS. Diversions above for irrigation and municipal supply affect low flow only. Mean discharge, in second-feet, and run-off, in acre-feet, June 1935

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet 13 _ .. 7,550 14,980 18 116,000 230, 100 23 16,100 31, 930 28. _ 7,420 14,720 14..... 7,550 14, 980 19.... 164, 000 325, 300 24 13,000 25, 790 29.... 6,480 12,850 15.. 14,400 28,560 20 123,000 244,000 25 14,600 28, 960 30 6,430 12, 750 16 _ .. 27,900 55, 340 21 67,800 134, 500 26 10, 900 21, 620 17 58, 700 116, 400 22 24,300 48,200 27 8,670 17,200 Eun-ofif, in acre-feet, or period June 13 -30...... 1,378,00- Gage-height, in feet, and discharge, in second-feet, at indicated time, 1935

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June IS June 17 June 22 20.15 50,500 8.94 9,260 8 ___ ... 20.70 53, 900 16.10 28,400 21.25 57, 700 14.40 22, 200 21.72 61,800 13.48 19, 300 7,350 8...... 22.36 68, 000 12 midnight 12.92 17,500 12 midnight. ... 7.90 6,750 12 midnight .... 23.16 75, 700 June 18 June 2S June 14 4 a. m ...... 23.75 82, 200 6 a. m _____ 12.75 16, 900 7.73 6,190 8...... 24.63 91, 700 12 noon... __ 12.53 16, 400 9 __ .... _ ... 7.73 6,190 12 noon...... 25.90 110, 000 12.05 15, 300 7.88 6,550 27.22 133, 000 12 midnight .... 11.55 13, 700 8.98 8,820 8 28.44 156, 000 12 midnight .... 10.00 11, 000 12 midnight .... 29.35 177, 000 11.10 12, 700 June 19 10.87 12, 200 6 a. m _____ 11.20 14, 000 3 a. m ...... 29.45 177, 000 2 p. m..._ ...... 10.87 12, 200 15, 000 6...... _ .. 29.35 177, 000 6 ...... 11.18 13, 000 12 noon...... 11.77 15, 500 9 ...... 29.00 168, 000 12 midnight .... 11.90 14,800 2 p. m . . 11.80 15, 500 12 noon...... 28.77 164, 000 4 _ . ______11.77 15, 500 4 p. m...... 28.56 160, 000 June 25 7 ..... 11.64 15, 000 *io. ou lOrt, UUU 3 a. m...... 12.10 15, 500 10 ____ . ... 11.50 14, 800 12 midnight .... 27.95 148, 000 5.. _____ ..... 12.14 15, 500 7 _ ...... 12.11 15, 500 June 16 6 a. m ...... 27.37 136, 000 9...... 12.05 15, 300 10.95 13, 200 26.77 125, 000 12 noon...... 11.86 15, 000 4...... 10.95 13, 200 6 p. m .. 25.94 110, 000 6 p. m ...... 11.34 13, 500 6 ...... 11.10 13, 700 12 midnight 25.00 97, 000 12 midnight .... 10.82 12,200 6...... 11.55 9... _ ...... 13.80 21, 500 June SI 15.75 28,400 23.80 82, 200 6 a. m. __ .. 10.42 11, 300 17.50 35, 900 22.60 68, 900 10.06 10, 600 8 .. _ ... 18.65 41, 900 20.83 52, 500 9.75 9,920 12 midnight .... 19.40 45,900 12 midnight .... 18.45 38, 800 12 midnight 9.49 9,260 NOTE. Discharge determined by shifting-control method except June 17 to 6 a. m. June 21. MAJOR TEXAS FLOODS OF 1935 263

NORTH LLANO RIVER NEAR JUNCTION, TEX. LOCATION. Lat. 30°30', long. 99°47', 500 feet above remains of old Wilson Dam and 3 miles northwest of Junction, Kimble County. Zero of gage is 1,699.9 feet above mean sea level. DRAINAGE AREA. 914 square miles. GAGE-HEIGHT RECORD. Water-stage recorder graph. Gage heights used to half tenths between 4.0 and 6.0 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 33,700 second-feet and extended above the peak stage. Definition doubtful above 33,700 second-feet and subject to revision. MAXIMA. 1935: Discharge, 47,400 second-feet 12:20 p. m. June 14 (gage height, 20.70 feet). 1915-34: Discharge, 48,100 second-feet Oct. 6, 1930 (gage height, 20.9 feet). 1875-1914: Stage, about 22.9 feet in 1889. REMARKS. Diversions for irrigation materially reduce low-water flow but do not affect flood flow. Mean discharge, in second-feet, and run-off, in acre-feet, June 1935

Second- Acre- Seocjnd- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

13...... 647 1,283 18 __ . 625 1,240 23. 200 397 28 136 270 14...... 22,300 44, 230 19 __ . 436 865 24, .... 185 367 29..... 129 256 15... _ . 4,890 9,700 20..... 274 543 25..... 166 329 30 .. 118 234 16. ___ . 646 1,280 21..... 242 480 26..... 155 307 17...... 403 799 22...., 219 434 27 140 278 Eu i-oflf, in £icre-feet, for perio<1 June IE -30 63,290

Gage-height, in feet, and discharge, in second-feet, at indicated time, 1985

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June IS June 15 June 19 Con. 1 a. m ...... 3.82 1,290 2 a. m.__ _ ... 9.10 12,600 12 noon. -- 2.23 370 4...... 3.36 942 4...... 8.00 10, 000 12 midnight . 2.07 299 3.00 700 6. __ 6.95 7,700 4 p. m ...... 2.57 462 9...... 5.55 4,560 June 90 12 midnight __ 2.38 379 4.72 2,860 4.00 1,790 2.01 274 8 ...... 3.50 1,220 2.44 474 3 90 Q79 3 ...... 2.56 538 4 ______. ... 3.40 1,130 1.93 242 5 . 5.55 4,560 6.. _ .... 8.30 10, 700 2.70 620 June K 7...... 13.90 12 midnight .... 2.46 484 8...... , . 15.35 30, 000 1.87 219 9 ...... 16.30 June 17 10...... ___ ... 17.60 36, 900 2.31 408 11, ______19.00 41, 600 46, 700 1.82 200 1 p. m ...... 20.50 46, 700 2.. _ . .. .. 19.00 41, 600 12 noon ...... 2.13 325 June 24 3.. ____ ...... 16.10 32, 200 6 p. m ...... 2.10 312 4.. _ ...... 14.30 26, 700 7 ______4.10 1,920 12 noon.. __ . 1.78 185 5.... _ ...... 13.10 23, 300 6...... 12.35 21, 300 9...... 3.85 1,600 June 25 7_...... 12.10 20, 500 10 .... 3.22 988 8...... 12.50 12 midnight .... 3.13 918 1.73 160 9...... 12.80 22, 400 10 ...... 12.20 20, 800 11... _ ...... 11.40 18, 600 2.92 764 12 midnight . 10.40 15, 900 6...... 2.46 484 12 noon..... 1.70 155 264 CONTRIBUTIONS TO HYDROLOGY, 1937

LLANO RIVER NEAR JUNCTION, TEX. LOCATION. Lat. 30°30', long. 99°44', 100 feet north of Kerrville-Junction road, 3 miles below confluence of North Llano and South Llano Rivers, and 3J4 miles east of Junction, Kimble County. DBAINAGE AREA. 1,762 square miles. GAGE-HEIGHT EECOED. Water-stage recorder graph except June 11-17, when it tfas determined from graph drawn from a partial recorder graph, gage read­ ings, and floodmarks. Gage heights used to halftenths between 3.5 and 5.4 feet to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 35,000 second-feet; extended to peak discharge on basis of four slope-area measurements. MAXIMA. 1935: Discharge, 319,000 second-feet 12 noon June 14 (gage height, 43.3 feet, from floodmarks). 1915-34: Discharge, about 106,000 second-feet Sept. 1, 1932 (gage height, 27.15 feet). 1889-1935: Discharge and stage, that of June 14, 1935. REMARKS. Small diversions and storage above station affect low flow only. Mean discharge, in second-feet, and run-off, in acre-feet, June 1935 Second- Acre- Second- A cre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet 13- 465 922 18 1,420 2,820 23 546 1,080 28 381 756 14.. 124, 000 246, 000 19 1,430 2,840 24 __ . 485 962 29 362 718 15.. _ .. 15, 700 31, 140 20 ___ 813 1,610 25.-.. 452 897 30 337 668 16.. . 3,310 6,570 21 ___ 649 1,290 26 420 833 17.. 1,400 2,780 22 .- 586 1,160 27 ___ 387 768 Ruii-ofl. in £ cre-feet, for period June 13- 30 303, 800 Gage-height, in feet, and discharge, in second-feet, at indicated time, 19S5 Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet June 18 June 15 June 19 Con. 2.31 434 13.1 22, 900 3.41 1,490 8 11.4 17, 800 3.44 1,520 14, 400 2 __ ...... __ . 3.40 1,480 8.6 10, 400 6 ...... 3.17 1,230 2.32 442 7.2 7,350 12 midnight .... 2.95 990 2.43 523 12 midnight .... 2.64 687 5.80 4,650 2.75 795 4.50 2,730 3.33 1,400 1,920 5. 4.00 2,150 3.54 1,640 6 _ 9.00 11, 300 2.57 649 7 17.0 37, 400 8 29.0 123, 000 3.32 1,390 9 37.0 221, 000 12 midnight .... 3.14 1,190 10 ___ 41.0 282, 000 2.48 686 11 ___ ...... 42.9 312, 000 43.3 319, 000 2.90 940 1,270 9 49 546 2 41.2 285, 000 8 ...... 3.57 1,640 3 39.2 254, 000 9- . 5,50 4,160 36.6 215, 000 10 . . ... 5.00 3,410 2.33 485 33.4 173, 000 11 4.52 2,750 6.. _ 29.6 130, 000 12 midnight .... 4.20 2,390 7... __ 25.8 94, 600 2 28 452 8- _ .... 22.0 65. 200 10. _ 17.7 40, 600 3.37 1,450 12midnieht--_- 15.6 31. son 10 3.12 1,170 12 noon. _ . ... 2-23 420

LLANO RIVER NEAR CASTELL, TEX. LOCATION. Lat. 30°43', long. 98°53', 4 miles above mouth of Hickory Creek and 6 miles east of Castell, Llano County. DBAINAGE AREA. 3,514 square miles. MAJOR TEXAS FLOODS OF 1935 265

GAGE-HEIGHT RECORD. Graph drawn from fragmentary staff-gage readings, floodmarks, and local information. Gage heights used to half tenths be­ tween 1.5 and 4.4 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 10,000 second-feet; extended to peak stage on basis of one float and one slope-area measurement. MAXIMA. 1935: Discharge, 388,000 second-feet 1 p. m. June 14 (gage height, 37.0 feet, from floodmarks). 1923-34: Discharge, 89,800 second-feet Oct. 6,1930 (gage height, 22.3 feet). 1889-1922: Stage, 28.4 feet in 1889 (discharge not determined). REMARKS. Small diversions above station affect low flow only. Mean discharge, in second-feet, and run-off, in acre-feet, June 1985

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

9. 15 .. 84, 700 168, 000 21. .... 1,010 2,000 27 _ .. 1,530 3,030 10.. - 16 ..... 7,940 15, 750 22. _ . 950 1,880 28..... 750 1,490 11. _ "562 '1,110 IT- 3,690 7,320 23..... 950 1,880 29..... 696 1,180 12 ...... IS- ... 1,780 3,530 24..... 880 1,750 30. .... 656 1,100 13 19 1,190 2,360 25..... 770 1,630 14..- ... 216, 000 428, 400 20 1,060 2,100 26..... 723 1,430 Euii-off. in acre-feet, for period June 9i30 650. 300

o Average for period June 9-13. * Average daily run-off for period June 9-13. Gage-height, in feet, and discharge, in second-feet, at indicated time, 1935

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June 10 June 15 Con. June 19 Con. 3.35 620 16.70 50,800 4.00 1,310 15.10 39, 700 6 ...... 4.24 1,670 13.70 31,200 8- __ ...... 4.07 1,410 4 ______12.60 26, 800 10 3.97 1,270 3.20 520 6 ...... 11.70 22,000 3.89 1,180 8- _ ...... 10.90 18,900 10 10.30 16, 700 12 midnight 9.60 14,400 3.10 470 3.68 1,050 June 16 June IS June SI 2 a. m ...... 9.10 12, 900 3.06 450 4... ___ ...... 8.60 11, 500 3.55 1.010 6.. _ ...... 8.10 10, 200 8...... 7.70 9,150 June 8& 10 7.40 8,420 4.00 1,310 7.00 7,460 3.50 1950 2 5.40 3,900 6.60 6,540 4.... ___ ...... 8.60 11,500 8 ...... 6.20 5,640 6. _ . _ .. 16.00 45,800 12 midnight . 6.90 4,980 8- ____ 25.40 149, 000 3.50 950 10 33.40 305, 000 36.80 383, 000 June 84 37.00 388,000 5.62 4,320 36.30 371, 000 5.28 3,690 3.43 880 4...... __ . 33.40 306, 000 4.98 3,090 6...... 30.60 243, 000 4.70 2,600 7 . 30.00 230,000 8 ____ . .. 31.40 260, 000 3.32 770 10 35.70 367, 000 11...... 36.00 364, 000 4.35 1,860 12 midnight 36.70 357, 000 4.06 1,380 12 midnight 3.80 1,070 3.27 723 June 15 June 19 32.60 287, 000 28.00 192, 000 3.65 900 6.. _ - ___ . 21.70 98,200 3.65 800 18.70 66,900 2p.m. 3.68 830

NOTE. Discharge determined by shifting-control method June 20-26. 58805 39 i 266 CONTRIBUTIONS TO HYDROLOGY, 1937

PEDEENAIES RIVER NEAR SPICE WOOD, TEX. LOCATION. Lat. 30°25'15", long. 98°04'50", in Travis County, 5.4 miles above confluence with Colorado River and 8 miles southeast of Spicewood, Burnet County. Zero of gage is 624.8 feet above mean sea level. DRAINAGE AKEA. 1,294 square miles. GAGE-HEIGHT RECORD. Graph drawn from two or more gage readings daily. Gage heights used to half tenths between 1.6 and 2.8 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 3,500 second-feet; extended to peak discharge by one slope-area measurement and three slope-area computations. MAXIMA. 1935: Discharge, 105,000 second-feet 10 a. m. June 15 (gage height, 32.0 feet, from graph based on gage readings). 1923-34: Discharge, 155,000 second-feet May 28, 1929 (gage height, 40.4 feet, from floodmarks). 1869-1922: Stage, about the same height as in 1929, occurred in 1869. REMARKS. No regulation or diversions.

Mean discharge, in second-feet, and run-off, in acre-feet, June 1935

Secon - Acre- Second- Acre- Day Second- Acre- Day feet feet Day feet feet feet feet

167 331 17 ___ ...... 24 19 368 730 18.. _ . ___ . _ . -106 t210 25... ___ .. 19 .... ___ .. 26 /655 13. _ ...... 3,250 6,450 20 ... __ .. 27...... 330 14 _ . _ ...... 6,360 12, 610 21..... _ - __ .. 15 ___ ...... 68,700 136, 300 99 9Q 16. . . _ . _ 2,820 5,590 oq i'3,210 d 6,370 30 174 345 Run-off, in acre-feet, or perioc June 11 30 180, 100

« Average for period June 17-21. 'Average daily run-off for period June 17-21. Average for period June 22, 23. ^Averase daily run-off for period June 22, 23. Average for period June 24-29. /Average daily run-off for period June 24-29.

GUADAIUPE RIVER NEAR SPRING BRANCH, TEX. LOCATION. Lat. 29°52', long. 98°23', at New Braunfels-Blanco highway bridge 4 miles southeast of Spring Branch, Comal County. Zero of gage is 947.37 feet above mean sea level. DRAINAGE AREA. 1,432 square miles. GAGE-HEIGHT RECORD. Water-stage recorder graph. Gage heights used to half tenths between 4.7 and 5.0 feet; hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 70,000 second-feet; extended above. MAXIMA. 1935: Discharge, 114,000 second-feet 5 a. m. June 15 (gage height, 41.30 feet). 1922-34: Discharge, 121,000 second-feet 2 a. m. July 3, 1932 (gage height, 42.10 feet). 1900-1921: Stage, 45 to 50 feet in 1900 (discharge not determined). REMARKS. Small diversions and regulation upstream affect low flow only. MAJOR TEXAS FLOODS OF 1935 267

Mean discharge, in second-feet, and run-off, in acre-feet, June 19S5

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

11...... 336 666 16 12, 300 24,400 21..... 1,520 3,010 26 945 1,870 12...... 585 1,160 17 4,030 7,990 22 1,340 2,660 27 845 1,680 13 ___ .. 2,190 4,340 18 2,810 5,570 23..... 1,910 3,790 28 770 1,530 14...... 5,890 11, 680 19 2,190 4,340 9d 1,340 2,660 29..... 695 1,380 15...... 66, 100 131, 100 20 1,770 3,510 25 1,070 2,120 30 645 1,280 Ruia-off. in £icre-feet. for nerioc June 11-30 216, 700

SAN ANTONIO RIVER NEAR FALLS CITY, TEX. LOCATION. Lat. 28°57'05", long. 98°03'55", at highway bridge half a mile above Scared Dog Creek and 3.4 miles southwest of Falls City, Karnes County. DRAINAGE AREA. 2,067 square miles. GAGE-HEIGHT RECORD. Water-stage recorder graph; no record June 18-25 (dis­ charge estimated). Gage heights used to half tenths between 3.9 and 4.6 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements. MAXIMA. 1935: Discharge, 14,300 second-feet 3 p. m. June 15 (gage height, 17.97 feet, affected by backwater); maximum gage height, 22.3 feet June 13, 1935 (affected by backwater). 1925-34: Discharge, 10,100 second-feet May 29, 1929 (gage height, 11.15 feet). 1875-1924: Stage, 28.36 feet in October 1913 (discharge not determined). REMARKS. Flow partly regulated by 254,000 acre-feet of storage in Medina Reservoir, on Medina River. Mean discharge, in second-feet, and run-off, in acre-feet, June 19S5 Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet 11 ...... 582 1,150 16 10, 800 21,420 21..... «3,270 '6,490 26 704 1,400 12.. __ . 2,290 4,540 17.. ... 7,820 15, 510 22 «3,270 66,490 27. .... 658 1,310 13...... 10, 800 21, 420 18 "3,270 66,490 23 "3,270 i>6,490 28 626 1,240 14...... 12, 400 24,600 19..... "3,270 66,490 24. .... "3,270 66,490 29 . 595 1,180 15 ...... 13, 800 27, 370 20 "3,270 '6,490 25- ... "3,270 66,490 30 ..... 564 1,120 Run-oft, in acre-feet, for period June 11-30 174, 200 »Average for period June 18-25. * Average daily run-off for period June 18-25. CIBOIO CREEK NEAR FALLS CITY, TEX. LOCATION. Lat. 29°01', long. 97°56', 200 feet downstream from Cestohowa Bridge, 6 miles above confluence with San Antonio River, and 6 miles north­ east of Falls City, Karnes County. DRAINAGE AREA. 831 square miles. GAGE-HEIGHT RECORD. Water-stage recorder graph except parts of June 12, 13, 14, 16, and 17 when recorder was submerged and graph drawn based on floodmarks and local information. Gage heights used to half tenths be­ tween 2.6 and 4.9 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 15,400 second-feet; extended above. MAXIMA. 1935: Discharge, about 28,600 second-feet 4 a. m. June 14 (gage height, 33.0 feet, from flood marks). 1931-34: Discharge, 6,390 second-feet July 30, 1933 (gage height, 21.5 feet, from floodmarks). 1913-30: Stage, about 38 feet in October 1913 (discharge not determined). REMARKS. No large diversions or regulation above station. 268 CONTRIBUTIONS TO HYDROLOGY, 1937

Mean discharge, in second-feet, and run-off, in acre-feet, June 1985

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

11. _ ... 270 536 16 3,140 6,230 21 - 339 672 26 110 218 12...... 1,120 2,220 17 3,290 6,530 22 248 492 27 _ .. 93 184 13.. 11, 000 21, 820 18 . 960 1,900 23 188 373 28 81 161 14.... 18, 100 35, 900 19 608 1,210 24 154 305 29 73 145 15 ___ . 1,980 3,930 20 . 465 922 25 182 254 30 ___ 66 131 Ruii-ofi, in £icre-feet. for perioc June 11 -30. 84. 130

NFECES RIVER AT IAGUNA, TEX. LOCATION. Lat. 29°26', long. 100°00', half a mile below Sycamore Creek and 1 mile northeast of Laguna, Uvalde County. DRAINAGE AREA. 764 square miles. GAGE-HEIGHT RECORD. Water-stage recorder graph. Gage heights used to half tenths between 4.4 and 7.6 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 40,000 second-feet; extended to peak discharge on basis of one float and one slope-area measurement. MAXIMA. 1935: Discharge, 213,000 second-feet 11 a. m. June 14 (gage height, 26.0 feet, from floodmarks). 1924-34: Discharge, about 87,200 second-feet June 15, 1930 (gage height, 20.1 feet). 1903-23: Discharge, 226,000 second-feet Sept. 21, 1923 (gage height, 26.5 feet). Stage, about 29 feet in June 1913 (discharge not determined). REMARKS. No diversions or regulation.

Mean discharge, in second-feet, and run-off, in acre-feet, June 19S5

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

11... 459 910 16 _ - 3,780 7,500 21 1,300 2,580 26 __ . 759 1,510 12 1,060 2,100 17 2,600 5,160 22 _ .. 1,170 2,320 27 _ .. 695 1,380 13 12,600 24, 990 18 2,030 4,030 23 1,090 2,160 28 643 1,280 14 107, 000 212, 200 19 1,700 3,370 24 932 1,850 29 595 1,180 15 12,100 24,000 20«. ... 1,520 3,010 25 828 1,640 30 562 1,110 Ruii-ofi, in acre-feet, or perioc June 11--30 304, 300

Gage-height, in feet, and discharge, in second-feet, at indicated time, 19S5

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June 10 June 18 June IS 4.15 498 4.02 435 4.40 633 5.50 1,920 3 ___ ... 5.25 1,490 2 ...... 5.70 2,280 5 ____ ...... 5.10 1,240 3. _ . ___ . .... 6.63 5,050 7 _ ...... 5.57 2,050 5 ___ . _ ..... 6.50 4,900 4.00 425 8 ...... 5.40 1,750 8 _____ .. _ . 6.72 5,210 6...... 4.12 483 10 _ . 5.70 2,280 11 6.60 5,050 8 4.30 578 11 5.74 2,350 6.70 5,210 12 midnieht __ 4.14 493 12 midnieht .... 5.65 2.190 2 P. m. __ -. 6.60 5.050 MAJOR TEXAS FLOODS OF 1935 269

(rage-height, in feet, and discharge, in second-feet, at indicated time, 1985 Contd.

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June IS Con. June U Con. June 18 7.70 11...... _ .. ... 14.10 25,200 4.23 O 19ft 4 ____ ...... 9.80 11,300 12 midnight .... 13.30 22,100 4.08 1,980 5 ...... 13.60 23,200 12 midnight.... 3 94 1,840 6 _ __ ... 14.10 25,200 June 15 7...... 13.30 22,100 12.60 19, 500 8.-...... 15.50 31,800 2.... ____ ... 11.95 17,400 « 16.20 36, 400 3-... _ ...... 12.75 20,200 3.82 1,700 10...... 15.70 33,000 4....-..- __ . 12.65 19,500 12 midnight .... 13.75 24,000 5..-.- ...... 12.20 18,100 6...... _____ . 11.65 16,200 June 14 7 __ ...... 12.40 18,800 3.60 1,520 8. . . 12.88 20,600 1 a. m ...... 13.30 22,000 Q 16,500 2 ___ ...... 13.50 22,800 10 , 10.55 13, 400 3 ____ ...... 14.30 26,100 11.- _ - _ ... 9.75 11, 300 3.34 1,300 4 __ . _ ...... 15.65 32, 400 9 QQ 10, 200 5 ... 17.60 49,200 8.53 8,500 «.. . 20.00 85, 500 8.00 7,530 7 ____ ...... 22.00 122, 000 Q 7.20 6,060 3.22 1,170 8 24.30 171, 000 6.65 5,050 fl 25.80 208, 000 10...... 25.70 206,000 11..... ____ . 26.00 213, 000 6 90 12 noon ...... 3.10 1,090 12 noon ...... 25.05 188,000 8 __ ... 5.85 3,920 24.80 loo, UUU 12 noon. -...... 5.63 3,660 June *4 2 ...... 25.60 203, 000 09 9QH 3.. ______. 25.30 196, 000 5 3 12 noon ...... 2.90 932 4 ...... 24.65 178, 000 12 midnight .... 5.06 2,990 5 ______. 22.90 140, 000 ___ . ___ .. 20.60 95,800 12 noon ...... 2.76 828 7 ______.. 67, 400 * O/ 2,760 8 ____ ...... 17.10 44,000 4.70 2,600 «...... 15.70 33,000 6 p. m ...... 4.54 2,440 10...... 14.85 28, 300 4 40 2,280 2.66 759

NUECES RIVER NEAR UVAIBE, TEX. LOCATION. Lat. 29°11', long. 99°54', at Tom Nunn Crossing, 4K miles below Galveston, Harrisburg & San Antonio Railway bridge, 7 miles west by south of Uvalde, Uvalde County. DRAINAGE AREA. 1,930 square miles, a large part of which is noncontributing at low stages owing to water entering fault a few miles above gage. GAGE-HEIGHT RECORD. Water-stage recorder graph prior to June 12, 1935; graph drawn from information furnished by local residents, readings of stage by railroad company at railroad bridge 4.5 miles upstream, and floodmarks subsequent to June 11, 1935. Gage heights used to half tenths between 3.2 and 5.1 feet prior to June 14 and between 1.2 and 2.6 feet after June 14; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 50,000 second-feet, extended to peak stage on basis of two slope-area measure­ ments. MAXIMA. 1935: Discharge, 616,000 second-feet at 4 p. m. June 14 (gage height, 36.9 feet, from floodmarks). 1927-34: Discharge, 188,000 second-feet Sept. 1, 1932 (gage height, 23.25 feet). 1910-26: Discharge, 229,000 second-feet June 1913 (gage height, 26.4 feet). REMARKS. No diversions or regulation. 270 CONTRIBUTIONS TO HYDROLOGY, 1937

Mean discharge, in second-feet, and run-off, in acre-feet, June 1935

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

12 ...... 395 783 17..... 12, 200 24, 200 22 1,630 3,230 27. . 605 1,200 13 . 1,760 3,490 18.-... 7,820 15, 510 23.. ... 1,260 2,500 28 570 1,130 14...... 147, 000 291, 600 19 4,980 9,880 24 990 1,960 29- 505 1,000 15 ..... 45, 000 89, 260 20 3,020 5,990 25. ... . 790 1,570 30 505 1,000 16 19, 000 37, 690 21 - 2,120 4,200 26 678 1,340 Ema-off, in £icre-feet, for periocI June 12-30 497, 500

Gage-height, in feet, and discharge, in second-feet, at indicated time, 1935

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June 11 June 15 June 19 12 midnight 1.82 404 18.40 78,800 8 a. m ...... 5.10 5,390- 4 ______.. 17.20 65, 200 4.70 4,590 1.80 395 6 ______.. 16.20 55, 000 4.30 3,860 8.. __ . ___ . 15.40 48,200 10 __ ..... 14.70 42,900 June £0 «a. m __ ._ 2.50 960 14.10 38, 700 2.95 1,640 13.30 33, 800 3.85 3,020 3.65 2,730 6 __ .... _ .... 12.70 30, 500 9 ...... 12.20 28,000 June £1 12 midnight .... 11.70 25, 500 2 a. m _____ 5.15 5,600 3.20 2,120 4. _ . __ ...... 5.80 6,900 6 ______. .... 6.60 8,740 8 ...... 8.20 12, 800 10.90 21, 600 9 _____ ...... 13.20 33, 200 10.20 18, 800 12 noon ...... 2.82 1,630 10 ___ .... __ . 17.40 67,400 9.50 16, 500 11...... 19.30 89, 900 12 midnight- 8.90 14, 700 20.80 110, 000 22.10 132, 000 2.45 1,260 2. ....- 22.80 145, 000 3 ...... 23.30 155, 000 8.40 13, 300 4 ___ 36.90 616, 000 7.90 12,000 6 36.20 585, 000 7.50 11, 000 2.15 990 6 ___ ...... 33.40 471, 000 7.00 9,700 7 __ . _ ...... 30.50 362,000 June £5 8 ...... 27.70 267, 000 9 ..... 24.30 177, 000 1.92 790 10 ______.... 22.40 138, 000 6.50 8,510 11...... 21.00 113, 000 6.00 7,360 12 midnight- 19.90 97, 700 5.50 6,240 3 p. m ...... 1.70 640

NUECES RIVER AT COTULIA, TEX. LOCATION. Lat. 28°26', long. 99°16', at Cotulla-Laredo highway bridge in Cotulla, LaSalle County. Zero of gage is 368.08 feet above mean sea level. DRAINAGE AREA. 5,260 square miles, a large part of which is noncontributing at low stages owing to water entering fault near Uvalde. GAGE-HEIGHT RECORD. Water-stage recorder graph except June 15-20, when graph was drawn from frequent gage readings. Gage heights used to half tenths between 11.6 and 12.8 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 37,000 second-feet, extended to peak stage on basis of one slope-area meas­ urement of the peak. MAXIMA. 1935: Discharge, 82,600 second-feet at 7 a. m. June 18 (gage height, 32.4 feet, from floodmarks). 1923-34: Discharge, 49,500 second-feet June 3, 1925 (gage height, 24.8 feet, present site and datum). 1899-1922: Stage, 29.7 feet, present site and datum, June 19, 1899 (dis­ charge not determined). REMARKS. Regulation and diversions affect low flow only. MAJOR TEXAS FLOODS OF 1935 271

Mean discharge, in second-feet, and run-off, in acre-feet, June 1935

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

l 994 1,970 9 3,420 6,780 17 32, 200 63, 870 25 2,890 5,730 2 1,600 3,170 10 3,890 7,720 18 79,000 156, 700 26 2,120 4,200 3 2,270 4,500 11 4,480 8,890 19 57, 600 114, 200 27 1,700 3,370 4 4,290 8,510 12 4,480 8,890 20 35, 300 70,020 28 1,390 2,760 5 6,480 12,850 13 4,010 7,950 21 21, 500 42, 640 29 1,170 2,320 6 5,600 11, 110 14 3,180 6,310 22 12, 600 24,990 30 1,010 2,000 7 3,770 7,480 15 3,300 6,550 23 7,550 14, 980 8 3,300 6,550 16 4,480 8,890 24 4,740 9,400 Run-off, in acre-feet, for period June 1- 30. ______... ______.. 635,300

Gage-height, in feet, and discharge, in second-feet, at indicated time, 1985

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June 9 June 16 Con. June SO Con. 12 midnight .... 13.49 3,420 1 p. m ...... 14.60 4,720 12 noon ...... 25.75 35,200 11 __ ...... 14.75 4,840 25.10 32,400 June 10 8 _ ..... 24.50 30,100 June 17 12 midnight.... 23.90 27,900 13.75 3,770 6 p. m ...... 14.14 4,240 14.85 5,470 12 midnight .... 14.39 4,480 3 ____ ... 15.00 5,730 4 ...... 15.13 5,880 23.25 25,400 5 ...... 15.35 6,330 8 ______. 22.60 23,300 6 _ . _ . _ .... 15.95 7,280 22.00 20,400 14.43 4,480 7 _ . _ ...... 17.20 9,500 21.35 19,600 12 midnight 14.47 4,480 8 _ ...... 18.30 11, 800 8 __ . ____ ... 20.80 17, 800 9.. _ ...... 19.45 14,300 20.25 16,200 June IS 10...... 20.60 17, 300 23.00 24,700 14.41 4,480 25.40 33, 600 14.41 4,480 4 __ ...... 27.60 44, 600 19.43 14,300 12 midnight . 14.35 4,480 6 ____ ...... 29.30 56,200 18.65 12,400 8 _ ... _ . _ .. 30.60 66, 600 17.92 10, 900 10 31.40 73,600 12 midnight 17.25 9,500 12 midnight .... 31.90 78, 100 14.18 4,240 13.96 4,010 6 p. m ...... 13.77 3,770 6 a. m ___ . ... 16.68 8,530 12 midnight .... 13.56 3,650 32.20 80,800 16.17 7,620 4 _ ...... __ .. 32.30 81, 700 15.72 6,800 6 .... ___ ... 32.40 82, 600 12 midnight 15.25 6,030 8 ___ ...... 32.40 82, 600 13.35 3,420 10 _ .... 32.30 81, 700 June 84 13.13 3,180 32.20 80, 800 6 p. m ...... 12.98 2,950 32.10 79, 900 6a.m...... 14.75 5,470 12 midnight .... 12.96 2,950 4 _ ...... 31.90 78, 100 12 noon. . ... 14.23 4,720 6.. __ .. ___ . 31.75 77, 200 13.72 4,130 9 ...... 31.45 73, 600 13.28 3,650 12 midnight .... 31.10 70,900 13.10 3,060 6... . __ ... 13.15 3,180 12 noon ...... 13.20 3,180 6 a. m ...... 12.95 3,300 13.42 3,420 30.65 66,600 12.67 2,890 8_ ...... 13.62 3,650 8 ...... 30.15 63, 400 6 p. m _ ...... 12.45 2,650 13.55 3,650 29.50 57, 800 12 midnight .... 12.30 2,470 28.90 53,300 8 ...... 28.25 48, 400 12 midnight .... 27.60 44,600 2 a. m ...... 13.65 3,650 12.15 2,300 4 ___ ...... 13.95 3,890 12noon._ ...... 12.02 2,120 6 ...... 14.26 4,240 11.93 2,060 10-, _ ...... 14.55 4,600 27.00 41, 000 11.83 1,950 1 p.m ...... 14.60 4,720 8 ______. 26.35 38,000

NOTE. Discharge determined by shifting-control method June 10-16. 272 CONTEIBUTI05TS TO HYDKOLOGY, 1937

NUECES RIVER NEAR THREE RIVERS, TEX. LOCATION. Lat. 28°26'10", long. 98°11'10", 100 feet below San Antonio* Uvalde and Gulf Railroad and 2 miles southeast of Three Rivers, Live Oak County. Zero of gage is 101.08 feet above mean sea level. DBAINAGB AREA. 15,600 square miles, part of which is noncontributing at low stages owing to water entering fault near Uvalde. GAGE-HEIGHT RECORD. Water-stage recorder graph. Gage heights used to half tenths between 3.5 and 4.8 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 55,000 second-feet and extended to peak stage. MAXIMA. 1935: Discharge, 66,700 second-feet at 6 a. m. June 15 (gage height, 44.67 feet). 1915-34: Discharge, about 85,000 second-feet Sept. 18, 1919 (gage height, 46.0 feet). Peak of Sept. 18, 1919, is maximum known. It is rumored that a similar height occurred about 1882. REMARKS. Small diversions for irrigation above station. Mean discharge, in second-feet, and run-off, in acre-feet, June 1986

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

1... __ 9,840 19, 520 9...... 16,400 32,530 17..... 23, 800 47, 210 25..... 40,000 79, 340 2_. _ .. 15,400 30, 550 10..... 12, 100 24,000 18. _ . 16,500 32, 730 26 30,900 61,290 3.. _ 18, 000 35, 700 11-. 11,200 22, 210 19 16,400 32,530 27 23,300 46, 210 4...... 17, 400 34, 510 12 13, 200 26, 180 20 22,400 44, 430 28 17, 500 34, 710 5_.._ 16, 300 32, 330 13 _ .. 22, 600 44, 830 21..... 26, 500 52, 560 29 12, 400 24, 600 6.. 19, 500 38, 680 14..... 61, 900 102, 900 22., ... 34,000 67, 440 30. .... 9,040 17, 930 7 25,400 50, 380 15 63,400 125, 800 23 53,500 106, 100 8...... 22, 600 44,830 16 44, 400 88,070 24.. ... 51, 000 101, 200 Ru n-ofl, in acre-feet, for period June 1--30 1, 501, 000

Gage-height, in feet, and discharge, in second-feet, at indicated time, 1935

Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June 1 June 6 June 11 la. m ...... 26.20 6,910 Q7 f\>7 18, 000 32.77 11, 100 6. ____ 28.35 7,850 37.92 20, 000 33.02 11, 300 10 _ ...... 30.86 9,270 qo 07 90 onn 12 midnight _ . 33.42 11, 800 3 p. m...... 32.58 10,700 33.70 12 000 12 midnight- ... 34.35 12, 900 39.47 25,600 33.95 12, 600 26, 500 34.63 13, 500 6.... _ ...... 39.66 12 midnight .... 35.50 15, 000 4 a. m ...... 34.87 14, 000 qQ 47 t)K fif\f\ 35.68 15, 300 36.25 16, 200 12 midnight .... 36.78 17, 400 36.60 17,000 38.98 38.45 21, 600 QQ 00 91 °.nn 39.85 26, 900 12 midnight 37.54 19, 000 12 midnight .... 41.30 35, 100 8 a. m ...... 37.05 17, 800 37.15 18, 300 12 midnight .... 37.02 17, 800 36.70 17, 200 42.33 42, 700 43.43 53, 000 36.78 14,300 43.93 58,000 12 midnight 36.45 8 ...... 44.30 62, 300 June 5 June 10 12 midnight _ . 44.53 64,500 36.17 16,200 QQ m 12,000 June IB 12 noon ...... 36.04 15,800 11, 100 44.65 65, 600 36.04 15, 800 32.60 in onn 44.67 66, 700 12 midnight. ... 36.47 16. 800 12 midnight. ... 32.60 10. 900 8 ____ . ___ 44,65 65, 600 MAJOE TEXAS FLOODS OF 1935 273 Gage-height, in feet, and discharge, in second-feet, at indicated time, 1935 Contd. Second- Second- Second- Time Feet feet Time Feet feet Time Feet feet

June 15 Con. June SO June S4- 44.56 65,600 43.44 53,000 44.37 63,400 38.05 20, 300 43.22 51, 000 B...... 44.12 60, 100 38.70 22,500 42.98 49, 000 12 midnight 43.80 57, 000 39.25 24, 400 42.72 46, 300 June 16 12 midnight .... 39.63 26, 100 June %5 6 a. m _____ 43.20 51,000 42.04 40,000 42.52 44,500 41.36 35, 800 41.68 37, 900 39.82 26, 900 12 midnight 40.75 32, 000 39.85 26, 900 39.70 26,500 40.63 30,900 9 _ ...... 39.65 26, 100 12 midnight 39.80 26,900 6 a. m _____ 39.78 26,900 11 ...... 39.65 26, 100 38.85 33.13 20,600 38.90 23,200 12 midnight 37.50 19,000 12 midnight 38.02 20,300 39.79 27, 000 6 ...... 40.05 27, 800 36.86 17, 600 40.98 33, 000 36.85 17, 400 36.26 16, 400 41.95 40, 000 12 midnight .... 35.43 14,800 35.88 15, 600 49 an 47, 200 12 midnight 35.75 15, 500 33.87 12, 500 12 midnight _ . 32.15 10, 500 35.85 15,500 43.37 53,000 36.20 16, 200 43.62 55, 000 36.75 17, 400 43.70 56, 000 30.25 9,000 12 midnight .... 37.37 18,800 12 midnight. ... 43.60 55, 000 12 midnight .... 28.20 7,850

FRIO EIVEK AT CONCAN, TEX. LOCATION. Lat. 29°29', long. 99°42', half a mile below Concan post office, Uvalde County. DRAINAGE AREA. 485 square miles. GAGE-HEIGHT RECORD. Water-stage recorder graph. Gage heights used to half tenths between 3.1 and 4.2 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 440 second-feet; extended to peak discharge on basis of two slope-area meas­ urements. MAXIMA. 1935: Discharge, about 86,900 second-feet 1:30 a. m. June 14 (gage height, 29.4 feet, from floodmarks). 1924-34: Discharge, 162,000 second-feet July 1, 1932 (gage height, 34.44 feet, from floodmarks). 1913-23: Stage 28.8 feet Sept. 18, 1923, from floodmarks (discharge not determined). REMARKS. No diversions or regulation. 274 CONTRIBUTIONS TO HYDROLOGY, 1937

Mean discharge, in second-feet, and run-off, in acre-feet, 1935

Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet

May June June 27...... 209 415 7 _____ . .... 421 835 20 ______948 1,880 28...... 3,740 7,420 8 ____ . __ . 395 783 21... _ ...... 876 1,740 29... _____ . 1,570 3,110 9... _ ...... 362 718 22 ...... 804 1,590 30 ____ . __ . 863 1,710 10...... 336 666 23. ___ ...... 733 1,450 31 2,380 4,720 11 __ ...... 473 938 24. __ ...... 694 1,380 12. __ . ____ . 668 1,320 25...... _ ..... 648 1,290 June 13 __ ...... 7,690 15, 250 26...... 616 1,220 1 ______824 1,630 14. __ ...... 22,700 45,020 27 _____ - .... 570 1,130 2...... 622 1,230 2,770 5,490 28. ___ .. _ ... 544 1,080 3 __ .. _ ..... 596 1,180 16.. . _ . ___ . 1,760 3,490 00 512 1,020 4... ___ ...... 480 952 17 __ . _ . 1,440 2,860 30. ______.. 486 964 5 707 1,400 18 ...... 1,240 2,460 6 ____ ...... 499 990 19. ______. 1,080 2,140 Eun-oflf, iti acre-fee t, for perk d May 27 to June 12 30, 020 Run-off, iti acre-feet, for perk d June 13-30. .... 91. 450

FRIO RIVER NEAR DERBY, TEX. LOCATION. Lat. 28°44', long. 99°09', at International-Great Northern Railroad bridge 900 feet below mouth of Leona River and 4 miles south of Derby, Frio County. Zero of gage is 449.3 feet above mean sea level. DBAINAGB ABBA. 3,493 square miles, a large part of which is noncontributing at low stages, owing to water entering fault a few miles below Concan. GAGE-HEIGHT RECORD. Water-stage recorder graph except June 1 to 4 and 14 to 19 when graph was drawn from numerous gage readings and floodmarks. Gage heights used to half tenths between 2.6 and 4.0 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE BELATION. Defined by current-meter measurements below 40,000 second-feet, extended to peak discharge on basis of one slope-area measurement of the peak. MAXIMA. 1935: Discharge, 68,300 second-feet at 4:30 a. m. June 2 (gage height, 23.68 feet, from floodmarks). Discharge, 49,000 second-feet at 7 a. m. June 16 (gage height, 20.8 feet, observed at peak). 1915-34: Discharge, 230,000 second-feet July 4, 1932 (gage height, 29.45 feet, from floodmarks). Peak of July 4, 1932, is maximum known. REMABKS. Small diversions for irrigation above station. Mean discharge, in second-feet, and run-off, in acre-feet, 1935

Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet

May June June 27 ...... 361 716 7...... 2,700 5,360 20. 2,920 5,790 28...... 155 307 8. _____ . _ . 1,600 3,170 21 2,280 4,520 29 ___ ...... 3,360 6,660 9 ____ ...... 922 1,830 22. ______... 1,910 3,790 30...... 15,900 31, 540 10...... 528 1,050 23.. ___ ...... 1,590 3,150 31...... 7,780 15, 430 11. _ . ___ . 412 817 24.. _____ ... 1,250 2,480 12...... _ ..... 937 1,860 25...... 1,010 2,000 June 13. _ ..... _ .. 2,280 4,520 26 _____ .. 882 1,750 1 ______. 16,700 33, 120 14...... 9,960 19, 760 27... ____ .... 806 1,600 2...... 55,400 109, 900 15...... 26,800 53,160 28. ___ ..... 733 1,450 3 _____ . _ . 17,500 34, 710 36...... ___ . 45, 800 90, 8-10 29.. ___ . __ . 663 1,320 4...... 5,640 11,190 17...... 24, 100 47, 800 30 ______... 595 1,180 5 ____ ...... 3,020 5,990 18.. _ . ___ ... 6,980 13, 840 6 ...... 2,290 4,540 19... ___ ..... 3,850 7,640 Run-off, i: i acre-fee t, for perk >d May 27 to June 12 268, 200 Run-off, iii acre-feet, for perk>d June 13 30 266, 600 MAJOR TEXAS FLOODS OF 1935 275

FRIO KITES AT CAIUHAM, TEZ. LOCATION. Lat. 28°29'30", long. 98°20'45", at Calliham-Whitsett highway bridge 1 mile north of Calliham, MeMullen County. Zero of gage is 153.47 feet above mean sea level. DRAINAGE AREA. 5,491 square miles, a large part of which is noncontributing at low stages owing to water entering a fault below Concan. GAGE-HEIGHT RECORD. Water-stage recorder graph except June 5 to 25, when graph was drawn from numerous gage readings. Gage heights used to half tenths between 4.5 and 5.3 feet; to hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 14,000 second-feet; extended to peak discharge on basis of one slope-area measurement of the peak. MAXIMA. 1935: Discharge, 28,600 second-feet at 7:40 a. m. June 6 (gage height, 33.42 feet, from graph based on gage readings. Discharge, 21,400 second-feet at 2 a. m. June 14 (gage height, 31.4 feet, from graph based on gage readings). Discharge, 26,600 second-feet at 7 a. m. June 20 (gage height, 32.9 feet, from graph based on gage readings). 1924-26, 1932-34: Discharge, 109,000 second-feet July 6, 1932 (gage height, 39.20 feet). Peak of July 6, 1932, is maximum known. REMARKS. Small diversions for irrigation above station. Mean discharge, in second-feet, and run-off, in acre-feet, June 1985 Seeond- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet 1...... 4,590 9,100 9...... 5,500 10, 910 17 5,120 10, 160 25 2,310 4,580 2...... 5,180 10, 270 10 3,640 7,220 18 9,120 18,090 26 1,920 3,810 3 ___ ... 8,650 17, 160 11 ..... 5,110 10, 140 19.. ... 20, 500 40, 660 27 1,640 3,250 4. __ ... 10,900 21,620 12..... 4,930 9,780 20 25,600 50, 780 28 1,410 2,800 5 __ . ... 18,100 35, 900 13..... 14,500 28, 760 21 17,900 35,500 29..... 1,240 2,460 6... .. 27,100 53,750 14..... 17, 600 34, 910 22..... 9,200 18, 250 30 810 1,610 7...... 19, 000 37, 690 15 ..... 10,500 20, 830 23 ..... 4,400 8,730 8... 10, 600 21, 020 16 7,410 14, 700 24..... 3,030 6,010 Run-off, in acre-feet, for period June 1-30 550,400

ATASCOSA RIVER AT WHITSETT, TEX. LOCATION. Lat. 28°39', long. 98° 18', 0.9 mile west of Whitsett, Live Oak County, and 4 miles below mouth of La Parita Creek. DRAINAGE AREA. 1,171 square miles. GAGE-HEIGHT RECORD. Water-stage recorder graph except June 13 to 15, when graph was drawn from local information and floodmarks. Gage heights used to half tenths between 5.5 and 7.2 feet; of hundredths below and tenths above these limits. STAGE-DISCHARGE RELATION. Defined by current-meter measurements below 7,500 second-feet, extended to peak discharge on basis of one slope-area measurement of the peak. MAXIMA. 1935: Discharge, 38,300 second-feet June 14 (gage height, 38.0 feet, from floodmarks). 1924-26, 1932-34: Discharge, 2,780 second-feet July 12, 1925 (gage height, 19.7 feet, present datum). 1922-23: Discharge, about 20,100 second-feet in April 1922 (gage height, 32.1 feet, present datum). Peak of June 14, 1935, maximum known. REMARKS. No diversions or regulation. 276 CONTRIBUTIONS TO HYDROLOGY, 1937

Mean discharge, in second-feet, and run-off, in acre-feet, June 1935

Second- Acre- Second- Acre- Second- Acre- Second- Acre- Day feet feet Day feet feet Day feet feet Day feet feet

1 ____ 2,140 4,240 9 _. 1,560 3,090 17 2,680 5,320 25 100 198 2 __ ... 5,800 11,500 10. . 1,920 3,810 18 463 918 26. . 88 175 3.. ... 1,110 2,200 11 5,840 11,580 19 295 585 27 80 159 4 ...... 340 674 12 - 5,480 10, 870 20.. ... 225 446 28 66 131 5...... 735 1,460 13 15,100 29,950 21 176 349 29- ... 61 121 6...... 351 696 14 36, 800 72, 990 22 148 294 30 56 111 7...... 175 347 15 17,300 34, 310 23 131 260 8 -.. 807 1,600 16 3,210 6,370 24 114 226 RUJn-ofl, in « cre-feet, for perioc[ June 1-30 205,000

DECEMBER FLOOD ON BUFFALO BAYOU GENERAL FEATURES The following is quoted from the United States Weather Bureau's "Climatological data," Texas section, for December 1935, page 96: Torrential rains in Harris County from December 6 to 8 caused phenomenal rises in Buffalo and Whiteoak Bayous. Authentic rainfall measurements during the period mentioned ranged from 5.52 inches at Houston to 16.49 inches at Satsuma, in the northwestern portion of the county. The two bayous have their confluence near the wholesale business district of Houston, from whence Buffalo Bayou flows through the city to Galveston Bay. Buffalo Bayou heads in southeastern Waller County at an altitude of about 180 feet and flows eastward about 55 miles across Harris County and through the city of Houston to its confluence with the San Jacinto Kiver, 7 miles above Galveston Bay. The area drained by Buffalo Bayou is entirely in the Coastal Plain. There is a heavy growth of trees and brush along the streams, but otherwise the area is not heavily wooded. Whiteoak and Little Whiteoak Bayous, tributary to Buffalo and Whiteoak Bayous respectively, drain a region to the north and east of and adjacent to the Buffalo Bayou drainage basin above the city of Houston. No detailed estimate of the damage caused by the flood was ob­ tained. Most of the damage occurred in the city of Houston. The following relevant information is taken from the United States Weather Bureau publication cited above: Approximately 100 blocks in the business and residential sections of the city were inundated, causing property damage of some $2,500,000, while 8 persons were drowned. Damage was done to buildings, household furnishings, bridges, roads, and merchandise. PRECIPITATION The rainfall data obtained are given in table 10, below. The rainfall records at Houston, Houston airport, Kichmond, and Sugar- land are quoted from the published reports of the United States Weather Bureau. The records at other points were obtained from MAJOR TEXAS FLOODS OF 1935 277 individual observers; some of the observers measured the rainfall in standard Weather Bureau type gages belonging to the city of Houston, and others measured the rainfall in tubs, barrels, cans, and other receptacles. TABLE 10. Precipitation in inches in Buffalo Bayou and adjacent drainage basins, December 6-8, 1935

No. on fig. 41 Station 6 7 8 6-8

1..... ___ ...... 0.10 4.95 0.47 5.52 2_ ...... Houston airport ______.. 1.05 2.22 2.99 6.26 3 ___ . _ . ... 4.15 6.10 10.25 4... ____ ...... 3.24 6.10 .07 9.41 3.06 4.12 7.18 6,...... 3.25 11.0 14.25 7.. ____ . __ .. 8.00 7.30 15.30 8...... M 17.0 17.0 ( ) 17.5 17.5 10 7.30 9.19 16.49 11.. ______.. ( ) 20.8 20.8 12...... Westfleld...... __ . __ ...... 5.16 15.48 20.64

Rainfall included in the next measurement. Figure 41 is a map showing the Buffalo Bayou drainage basin above Lockwood Drive bridge in Houston and parts of adjacent river basins, and other features.

MAXIMUM DISCHARGE The maximum discharges at several points were determined from rating curves based on current-meter measurements made during the flood by M. J. McCall, bridge engineer, Harris County. All discharge figures are taken from a report by Mr. McCall. The drainage areas were measured on topographic maps. Table 11 gives the results of discharge measurements made on Buffalo Bayou and tributaries. Figure 42 shows a hydrograph of the discharge of Buffalo Bayou at the Galveston, Harrisburg & San Antonio Railroad Eureka Cutoff bridge. The run-off for the flood period at this bridge is given in table 12. TABLE 11. Maximum discharge, Buffalo Bayou and tributaries at Houston, for flood of December 9, 1935

Maximum discharge

No. on fig. 41 Place of determination area Second- (square Second- feet per mile) feet square mile

1 ___ ...... 319 40,030 125 2 458 52, 750 115 3 - Whiteoak Bayou at railroad bridge west of Stude Park ...... 85.3 14, 750 173 4 _ ..... _ .. 18.1 4,950 273 O Westfield fcO

95050' »3°ZO>

X Numbers refer to discharge measurement stations In tables 11 and 14 95°so'

Numbers 'refer to precipitation Sugar Land stations in table 10 J 012545 MILES

FIOUBE 41. Isohyetal map of the Buffalo Bayou Basin showing discharge measuring places, intermediate drainage areas, rainfall stations, and total rainfall, in inches, December &-8,1935. 45

40

35

30

20

15

10 7/ 10 11 12 December FIGUEB 42. Hydrograpb of discharge, Buffalo Bayou at Eureka Cutoff railroad bridge at Houston, December 7-12,1935. IsD 280 CONTRIBUTIONS TO HYDROLOGY, 1937

TABLE 12. Run-off, in acre-feet, gage height, in feet, and discharge, in second-feet, on Buffalo Bayou at Eureka Cutoff bridge, Houston, December 7-12, 1935

Acre- Acre- Day feet Day feet

Dec. 7, noon to midnight 6,350 Dec. 1 3 . -.- .. . .. 44,000 Dec. 8 50,600 Dec. 1 L ______. __ _ _ . _ _ _ 25,000 71,800 Dec. 1 2, midnigl 9,120 Total 206,900

Dis­ Dis­ Dis­ Gage charge Gage charge Gage charge Time height (second- Time height (second- Time height (second- (feet) feet) (feet) feet) (feet) feet)

Dec. 7 Dec. 9 Dec. 11 1 p. m ...... 25.0 3,300 2 a. m _____ 60.8 40,030 12 noon...... 39.8 12, 410 6 _ ...... 30.7 6,420 6-_.._ 60.7 39,840 12 midnight __ 36.3 9,960 12 midnight .... 37.7 10,940 12 now I...... 59.1 35,980 6 p. m 57.7 32, 830 Dec. It Dec. 8 12 midnight . 55.6 29, 020 D c.10 34.5 8,725 45.0 16,400 52.0 23, 700 53.2 25,320 59.0 35,700 12 nooi 50.6 22, 060 12 midnight-­ 60.7 39,840 6 p. m 47.4 18, 700 12 midnight. ... 44.5 16,000

High-water altitudes along Buffalo Bayou were determined at several places by the Department of Public Works, city of Houston, and the data presented in table 13 were taken from profiles prepared therefrom. Figure 43 shows profiles plotted from the data presented in this table. PREVIOUS FLOODS The following information regarding previous floods in relation to that of December 1935 is quoted from the Monthly Weather Keview for December 1935, page 361: Levels run by the city engineer show a stage of 40.3 feet above mean tide level immediately below the confluence of the Buffalo and Whiteoak Bayous, as com­ pared with 34.3 feet on May 31, 1929, and 34.3 feet in 1879 (date unknown). The crest passed in the early morning of December 9. An unusually high stage is reported as having occurred in 1854, but no information concerning it is available. __^ .rTop of roadway on bridge ^--- -. 1 Eureka Cutoff bridge (G.H.& S.A.R.R. ) --- ^ s-H igh water, Dec. 9, 1935 2 Shepherd Drive bridge ^ Ms in Street bridge 3 Waugh Drive bridge 1 < - - -. [crown of irch) 4 Sabine Street bridge K - -^ 5 Capitol Avenue bridge M 3 ~ . ~T~ 6 Preston Avenue bridge & "\r 7 Smith Street bridge 4* ] 8 Franklin Avenue bridge m 2 o T 5 9 Milam Street bridge 0. \ f ^-- 10 San Jacinto Street bridge V ^ 30 9 ^ T \ ~~\.

\

.-Bot ;om of chaimel, June 1929 - sm jaCD bO , \ 14 13 12 11 10 98765 4 Distance In miles above turning basin FIGTJBE 43, High-water and stream-bed profiles of Buffalo Bayou from Post Oak Road to the turning basin at Houston, December 9,1935. to 00 282 CONTRIBUTIONS TO HYDROLOGY, 1937

TABLE 13. Crest stages, flood of December 9, 1985, and stream-bed altitudes determined June 1929, of Buffalo Bayou at Houston

Altitude above mea Q sea level Distance (feet) above basin Flood Stream Road­ (miles) crest bed way

Post Oak Road ______, ______14.90 62.4 Eureka Cutofl bridge ______14.06 60.2 8.7 56.5 12.31 56.3 7.1 Shepherd Drive bridge.. ______10.31 52.0 3.9 41.9 Waugh Drive bridge- ______9.50 50.1 .6 46.9 9.06 49.9 2.0 Sabine Street bridge ______7.94 47.9 -3.9 44.6 Capitol Avenue bridge. ______7.10 47.1 -3.9 40.5 6.78 46.7 -7.9 36.0 Smith Street bridge __ .. ______6.70 46.5 -4.9 36.7 Franklin Avenue bridge ______6.60 44.9 -4.4 35.9 6.50 41.0 -3.9 28.4 Main Street bridge ______6.39 40.3 -8.2 56.0 San Jacinto Street bridge ______6.25 39.7 -9.3 41.7 5.81 38.3 -14.0 5.62 37.2 -10.0 Houston Belt & Terminal Ry. Co. bridge.. ______5.31 36.5 -11.9 5.00 35.8 -13.9 4.82 34.1 -13.0 San Antonio & Aransas Pass R. R. bridge. ______4.19 32.1 -13.0 3.12 26.2 -13.0 1.25 19.4 -14.0 .88 18.1 15.9 .12 13.5 -16.5 Turning basin 0 12 7 -25.9

a Crown of concrete arch. SUMMARY OF MAXIMUM DISCHARGES Table 14 presents a summary of the maximum discharges that occurred on various streams in Texas during the major floods of 1935. The drainage area and discharge per square mile are given for each gaging station. For purposes of comparison the maximum previously recorded stages and the discharges, if known, are given. TABLE 14. Maximum stages and discharges on certain streams in Texas

Maximum stage and discharge Maximum stage and discharge, 1935 previously recorded

Drainage Lati­ Longi­ Discharge No. on Stream and place of determination area Period of maps tude tude (square record Discharge miles) Date Stage (second- Date Stage Second- (feet) feet) (feet) Second- feet per feet square mile

Buffalo Bayou Basin 1 Buffalo Bayou at Eureka Cutoff bridge, 0 / 0 1 29 45 95 27 319 1855-1935 May 1929 « 19, 000 Dec. 9 * 40, 030 125 2 Buffalo Bayou at Lockwood Drive bridge, 29 45 95 19 458 1855-1935 May 1929 « 30, 500 Dec. 9 ' 52, 750 115 3 Whiteoak Bayou at railroad bridge west of 29 47 95 23 85.3 1855-1935 ( ) Dec. 9 '14,750 173 4 Little Whiteoak Bayou at Sylvester Street, 29 49 95 23 18.1 1855-1935 ( ) Dec. 9 '4,950 273 Colorado River Basin 5 31 13 98 34 <« 30, 600 1900-1935 Sept. 1900 57.5 « 184, 000 May 19 41.00 '86,000 4.57 6 30 16 97 45 <« 38, 150 1843-1935 July 1869 43.0 June 15 42.0 > 481, 000 18.3 7 30 01 97 10 <« 39, 650 1913-1935 Dec. 1913 *47.4 June 16 42.5 ' 305, 000 11.0 8 29 35 96 25 <« 40, 940 1913-1935 Dec. 1913 » 32.0 June 19 29.45 ' 177, 000 »6.07 9 30 30 99 47 914 1875-1935 1889 22.9 June 14 20.70 / 47, 400 51.9 10 30 30 99 44 1,762 1889-1935 < ) June 14 43.3 '319,000 181 11 30 43 98 53 3,514 1889-1935 1889 28.4 June 14 37.0 ' 388, 000 110 12 30 15 99 57 540 June 14 (») ' 160, 000 296 13 30 18 99 53 218 1923-1935 < ) June 14 * 69, 300 318 14 30 25 98 05 1,294 1869-1935 May 1929 40.4 155, 000 June 15 32.0 105,000 81.1 Ouadalupe River Basin 15 Quadalupe River near Spring Branch ...... 29 52 98 23 1,432 1900-1935 July 1932 * 42. 10 « 121, 000 June 15 41.30 114, 000 79.6 16 28 57 98 04 2,067 1875-1935 Oct. 1913 28.36 June 15 '17.97 / 14, 300 6.92 17 Cibolo Creek near Falls City... ___ . _ .. ... 29 01 97 56 831 1913-1935 Oct. 1913 38 June 14 33.0 28,600 34.4 See footnotes at end of table.

bO 00 CO TABLE 14. Maximum stages and discharges on certain streams in Texas Continued to

Maximum stage and discharge Maximum stage and discharge, 1935 previously recorded Drainage Lati­ Longi­ Period of Discharge No. on Stream and place of determination area maps tude tude (square record Discharge miles) Date Stage (second- Date Stage Second- (feet) feet) (feet) Second- feet per feet square mile

Nueces River Basin 0 / 18 29 26 100 00 764 1903-1935 June 1913 29 June 14 26.0 ' 213, 000 279 19 Nueces River near Uvalde.. ______29 11 99 54 1,930 1910-1935 June 1913 26.4 ' 229, 000 June 14 A 36. 9 < 616, 000 319 20 28 26 99 16 5,260 1899-1935 June 1899 29.7 June 18 A 32. 4 < 82, 600 15.7 21 28 26 98 11 15, 600 1915-1935 Sept. 1919 * 46.0 85, 000 June 15 44.67 / 66, 700 4.28 22 29 44 100 24 402 June 14 (») « 580, 000 1,440 23 29 20 100 06 880 June 14 (*) ' 536, 000 609 24 29 29 99 42 485 1913-1935 July 1932 * 34. 44 ' 162, 000 June 14 29.4 < 86, 900 179 25 28 44 99 09 3,493 1915-1935 July 1932 *29.45 < 230, 000 June 2 23.68 / 68, 300 19.6 26 Frio River at Calliham ______28 30 98 21 5,491 1924-1935 July 1932 * 39. 2 < 109, 000 June 6 33.42 / 28, 600 5.21 27 29 31 99 49 120 June 14 (») < 64, 700 539 28 29 26 99 17 153 May 31 (») < 230, 000 1,500 29 28 39 98 18 1,171 1922-1935 Apr. 1922 32.1 20,100 June 14 * 38. 0 « 38, 300 32.7 Rio Grande Basin 30 29 20 100 54 123, 318 1900-1935 Sept. 1932 34.5 «' 605, 000 June 14 "23.63 195, 000 31 28 43 100 31 126, 962 1900-1935 Sept. 1932 49.0 ' 569, 000 June 15 33.23 199,000 32 29 21 100 53 62 1931-1935 Sept. 1934 14.47 11,300 June 14 23.20 45,000 726 33 29 15 100 46 524 1932-1935 Sept. 1932 17.10 44,800 June 14 30.2 < 215, 000 410 34 29 12 100 42 229 1928-1935 Aug. 1932 21.08 * 54, 650 June 14 « 11. 15 14, 600 63.8

« Record from Engineering Department, city of Houston. * Greatest stage known to local residents. Record from M. J. McCall, engineer for Harris County. ' Discharge by slope-area method. Stage less than in 1935. < Discharge from poorly defined rating curve. d 11,800 square miles noncontributing. * Stage 45 to 50 feet in 1900, discharge not determined. Discharge from extension of rating curve. ' Maximum stage June 13, 22.3 feet (backwater). / Discharge from well-defined rating curve. *» Record from Water Bull. 5, International Boundary Commission, United States and Mexico. Based on effective area. » Maximum for June, not maximum for year. INDEX

A Page Tan Blackwood Creek, Nebr., flood crest on___ 36 Abstracts of reports ______1, Blanchard Canyon, Calif., discharge of. 67,82 21, 53-54, 99-100, 163, 181-182, 223-224 Bloomington, Nebr., Republican River at, Acknowledgments for aid ____ 25, 55, 104, 183, 228 discharge of_ 45 Acre-foot, definition of ______227 Bonner Springs, Kans., Kansas River at, dis­ Agriculture, Avra-Altar Valley, Ariz ___ 170-171 charge of______39,46, pi. 13 Gila and San Simon Valley , Ariz. . . __ 187-188 Bonneville. See Lake Bonneville. Alluvial land, Avra-Altar Valley, Ariz., water­ Bostwick, Nebr., Republican River at, dis­ bearing qualities of ______173, pi. 41 charge of.__...- 49 Avra-Altar Valley, Ariz., wells in. 175-177, pi. 41 Brackettville, Tex., West Nueces River near, Gila Valley, Ariz., features of.... 163-164, pi. 47 discharge of . 252-256,284, pi. 52 Andrews, D. A., Ground water in Avra-Altar Brand Canyon, Calif., discharge of . 67-98 Valley, Ariz _ __ . 163-180, pis. 41-44 Brand Park, Glendale Highlands, Calif., land­ Arikaree River, Colo.-Nebr., discharge of. __ 36,45 slide in__.__...... __ 95, pi. 32 flood on... ______32-33 Brown, R. W., fossils identified by_____ 199 flood on, damage by ______40-44 Bryan, Kirk, quoted.__.______. 166,197-198 progress of crests ______33-34 Buffalo Bayou, discharge of, at Houston, Arroyo Seco, Calif. , discharge of ______97 Tex.... _....__... 277-282,283 Artesian conditions, in Avra-Altar Valley flood in, damage by.___ 276 Ariz...... 174 precipitation contributing to. 276-278 in Gila and San Simon Valley, Ariz. _ 208-212 in Ogden Valley, Utah....- ______. 120-122 0 Artesian reservoir, Ogden Valley, Utah, dis­ Calliham, Tex., Frio River at, discharge of. 275,284 charge from ______137-140 Cambrian quartzite, in Gila and San Simon probable effect of Pine View Reservoir Valley, Ariz.__..... ___ 195 on...... _ ... 143-144 Cambridge, Nebr., Republican River at. pi. 12 relation of, to stream flow ____ 144-146, pi. 37 Carrizo Springs, Tex., wells near, study of. 6-8, pi. 1 Artesian Park, Utah, Middle Fork of Ogden Castell, Tex., Llano River near, discharge River near ______112, 113 of .. 245,246,264-265,283 North Fork of Ogden River at, discharge Central Plateau of Texas, features of____.. 228 of...... 114, pl.39 Cerro Colorado, Ariz., geologic character South Fork of Ogden River near, discharge of .. . 172, pi. 42 of...... 111,113, pis. 37-38 Chambers, A. A., analyses by____ 179-180 wells at, analyses of water from ____ 160-161 Champion, Nebr., Frenchman Creek near, discharge from ______125, pi. 37 discharge of___ 48 Atascosa River, discharge of, at Whitsett, Check dams, Calif., features of....__ pis. 20,33 Tex_ ...... _ ..... 275-276, 284 Chief of Engineers, United States Army, flood on. _ ...... __ ...... 256-257 quoted..______49 Atlantic City area, N. J., wells in, salt-water Cibolo Creek, discharge of, near Falls City, leaks in ______4 Tex....__ ...... 267-268,283 Austin, Tex., Colorado River at, discharge Clay Center, Kans., Republican River at, dis­ Of .... _ ...... 241, 242, 259-260, 283 charge of._ . 45 B Climate, Avra-Altar Valley, Ariz. __ 167-168 Gila and San Simon Valley, Ariz. ..- 186-187 Baboquivari Mountains, Ariz., geologic char­ Ogden Valley, Utah.- . 105-106, pi. 35 acter of.. ______172, pi. 42 Coastal Plain of Texas, features of____... 229 Balcones fault zone, Tex., features of ____ 228-229 Colorado River, altitude and descent of 240 Barnston, Nebr., Big Blue River at, discharge discharge of, at Austin, Tex_____ 241, of...... 47 242,259-260,283 Bell, J. A., and Hawgood, H., quoted.. ___ 69 at Smithville, Tex 241,242,260-261,283 Beloit, Kans., Solomon River at, discharge of. 47 near Eagle Lake, Tex_._ 241,242,262,283 Big Blue River, discharge of, at Barnston, near San Saba, Tex. . 241,242,258-259,283 Nebr...... _ 47 flood on...._... 236-237,239-241,242, pis. 59-60 discharge of, at Hull, Kans. ____ . __ 48 Concan, Tex., Frio River at, discharge of. 273- at Manhattan, Kans______52 274,284 at Randolph, Kans ______48 Control, definition of______227 285 286 INDEX

Page Page Cotulla, Tex., Nueces Eiver at, discharge Fish Creek, Calif., discharge of 97 of...... __..._... 248,249,270-271,284 debris in______81-82,84, pis. 26-27 Coyote Mountains, Ariz., geologic character Flood, damage by, in Colorado 43 of-...... 171 damage by, in Kansas 43-44 Cretaceous rocks, in Avra-Altar Valley, Ariz 172 in La Canada Valley, Calif . 68-69, pi. 19 Culbertson, Nebr., Frenchman Creek at, dis­ in Nebraska. 43 charge of..... -.--. .- 46 in Eepublican Eiver-Kansas Eiver Eepublican Eiver at, discharge of 45 Basin______40-44 in Texas.. 237,276, pis. 56-57,60-«1 Flood discharges, in Eepublican Eiver- Kansas Eiver Basin, general Daingerfield, L. H., quoted...... 60-61,98 features of__. 32-33 Dalrymple, Tate, and others, Major Texas in Eepublican Eiver-Kansas Eiver Basin, floods Of 1935._..... 223-284, pis. 54-62 measurements of. 44-52 Debris, composition of ..- _... 88-92, pi. 30 in Texas ___.. _. ______257-284 measurement of______92-93, pi. 30 determination of.__ 229-232 movement of, across debris cone_____ 80-87 Fluorine, relation of, to mottled enamel of adaptation of stream bed to_ 74-80, pi. 24 teeth...... 220 by La Canada Valley flood__.__ 69-93 Follansbee, Eobert, and Spiegel, J. B., Flood factors influencing- . ..__ 74,88-92 on Eepublican and Kansas Eivers sources of______93-9C, pis. 17,21-22,31-34 May and June 1935.. 21-52, pis. 10-15 Deer Canyon, Calif., discharge of_.____ 83 Frenchman Creek, discharge of, at Culbertson, Definition of terms. _ . . 227 Nebr... . 46 Del Eio, Tex., Pinto Creek near, discharge of. 284 discharge of, near Champion, Nebr. 46 San Felipe Creek near, discharge of.___ 284 near Hamlet, Nebr_ 46 Delaware Eiver, discharge of, at Valley Falls, flood crest on. __.. . 36 Kans___ - ..._____ 48 Frio Eiver, discharge of, at Calliham, Tex... 275,284 Derby, Tex., Frio Eiver near, discharge of.. 274,284 discharge of, at Concan, Tex...... 273-274,284 D'Hanis, Tex., Seco Creek near, discharge of. 284 near Derby, Tex__.. 274,284 Drainage, Avra-Altar Valley, Ariz___ 167, pi. 43 flood on______...... 256 Ogden Valley, Utah ...... ___ 106-107 Texas....__._....._._..... 224-227, pi. 54 G Dry Frio Eiver. discharge of, near Eeagan Wells, Tex...... 284 Gazin, C. L., fossils identified by. ... 198 flood on... ___...... ___ 256 Geography, Avra-Altar Valley, Ariz . 165-171, Dunsmore Creek, Calif., debris in, composi­ pis. 41-44 tion of______91 Gila and San Simon Valley, Ariz.. 183-188, pi. 45 erosion by______84-86, pis. 27-28 Geologic history, Gila and San Simon Valley, Ariz., summary of... 204-205 E Geology, Avra-Altar Valley, Ariz 171-174, pi. 41 Gila and San Simon Valley, Ariz.. 194-205, pi. 46 Eagle Lake, Tex., Colorado Eiver near, dis­ Ogden Valley, Utah, general features of.. 107-110 charge of .. 241,242,262,283 Gila conglomerate, character, thickness, and Eagle Pass, Tex., Eio Grande at, discharge of.. 284 distribution of.. 196-198, pis. 45-46,50-52 Electrical-conductivity method of locating fossils from...... 198-200 salt-water leaks in wells_ 12-19, pis. 3-9 occurrence of....__..... 195 Ellsworth, Kans., Smoky Hill Eiver at, dis­ wells in...... 208-212, pi. 46 charge of._ ...______. 47,52 Gila Mountains, Ariz., geologic character of... 195 Endicott, Nebr., Little Blue Eiver near, dis­ Gila Eiver near Solomonsville, Ariz., dis­ charge of_ charge of______207, pi. 47 Engineer quoted______97-! Gila Valley, Ariz., features of . 190-194, pi. 47 Enterprise, Kans., Smoky Hill Eiver at, dis­ Gilbert, G. K., quoted ...... 74,75,197 charge of_ .. ..______47 Glaciation, effect of, on Ogden Valley, Utah _ 108 Erosion, causes of, in Gila Valley, Ariz___ 190-194, Graham Mountains, Ariz., geologic character pis. 47,49 of __.....___ 195, pi. 49 causes of, in San Simon Valley, Ariz__ 188-190 Green, Eobert A., analyses by. .. . 179-180 Ground water, development of, in Avra-Altar F Valley, Ariz..... 174-177, pi. 41 discharge of, Ogden Valley, Utah____ 136-141 Falls City, Tex., Cibolo Creek near, discharge occurrence of, Ogden Valley, Utah___ 119-120, Of ____.._.______267-268,283 pi. 36 San Antonio Eiver near, discharge of. _ 267,283 quality of, in Avra-Altar Valley, Ariz 177-180 Faults, occurrence of, in Gila and San Simon in Gila and San Simon Valley, Ariz.. 217-222 Valley, Ariz...... ___ 194-195 in Ogden Valley, Utah .. 142,160-161 occurrence of, in Ogden Valley, Utah___ 107 recharge of, Ogden Valley, Utah..___ 131-136 Fiedler, A. G., quoted...______8 source of, in Gila and San Simon Valley, Field work_____ 3,23,55,100-101,165,183,227-228 Ariz______.__-______207-217 Fire, Pickens Canyon, character and extent of. 60 in Ogden Valley, Utah..______120-121 INDEX 287

Page Fan Quadalupe River, discharge of, near Spring Kansas State Historical Society Transactions, Branch, Tex ..____ 266-267,283 quoted...______.__ 51 Kidwell, C. H., analyses by______179-180 H Kleberg County, Tex., wells in, study of _ 10, 16-18,19, pis. 6-9 Haigler, Nebr., Arikaree River at, discharge of. 39,45 Knechtel, M. M., Geology and ground-water Haines Canyon, Calif., check dam in_____ pi. 33 resources of the valley of Gila dischargeof ...... ____ 65-67 River and San Simon Creek, debris in, composition of ______91-92, pi. 30 Graham County, Ariz. 181-222, pis. 45-53 measurement of______92-93, pi. 30 Kramer, E. W., quoted. ______68 source of..______96, pi. 34 Hamlet, Nebr., Frenchman Creek near, dis­ charge of... 46 Hardy, Nebr., Republican River near, dis­ La Canada Valley, Calif., discharge of 65-68 charge of...______45 fire adjacent to.______.__.. 60 Hawgood, H., and Bell, J. A., quoted_____ 69 flood in, damage by______68-69, pi. 19 Hondo, Tex., Anvil Herald quoted..__ 232-233,236 debris in______69-93 Honolulu, Hawaii, wells in, study of._____ 8 rainfall in. ______58,60-65 Houston, Tex., Buffalo Bayou at, discharge of. 283 soil of... .__ 58 Hull, Elans., Big Blue River at, discharge of_ 48 topography and drainage of.. 56-58, pis. 16-18 Huntsville area, Utah, South Fork of Ogden vegetation in . 59 River near, discharge of...____ 111, Laguna, Tex., Nueces River at, discharge of.. 248, 113, pis. 37-38 249,268-269,284 Huntsville Spring Creek near, discharge Lake beds. See Gila conglomerate. of...... 112-113 Lake Bonneville, Utah, history of 108-110 Landslides, in La Canada Valley, Calif., fea­ tures of.______. 94-95, pis. 32, 34 Lawrence, Kans., Wakarusa River near, dis­ Igneous rocks, occurrence of, in Gila and San charge of.._.. 48 Simon Valley, Ariz______195 Lecompton, Kans., Kansas River at, discharge Indian traditions regarding floods, in the Re­ of._ 39,52 publican River-Kansas River Leggette, R. M., and Taylor, G. H., Geology Basin...... ______. 50-51 and ground-water resources of Og­ Isohyetals, definition of ______227 den Valley, Utah. . 99-161, pis. 35-40 Limestone, commercial production of, in Avra- Altar Valley, Ariz.....__...... 172 Lindsborg, Kans., Smoky Hill River at, dis­ Jarboe, J. H., quoted...... ____ 234 charge of.______47 Johnson grass, Avra-Altar Valley, irrigation Litigation, suspension of, among Ogden Valley, of.._.__....______... 171,173 Utah, water users______103 Junction, Tex., Llano River near, discharge of. 245, Little Blue River, discharge of, at Waterville, 246,264,283 Kans______48 North Llano River near, discharge of___ 245, discharge of, near Endicott, Nebr__ 48 246,263,283 Little Whiteoak Bayou, discharge of, at Hous­ Junction City, Kans., Kansas River near, dis­ ton, Tex _..___.__.... 283 charge of...... 39 Livingston, Penn, and Lynch, Walter, Meth­ Republican River at...... ___ 52 ods of locating salt-water leaks in water wells... 1-20, pis. 1-9 K Llano River, altitude and descent of 243 discharge of, near Castell, Tex.245,246,264-265,283 Kansas City, Kans., Kansas River at, dis­ near Junction, Tex_____ 245,246,264,283 chargeof...____.______39 flood on__....___ 236-237,241-245,246, pi. 56 Kansas River, discharge of.______37-39, pi. 13 Location of Avra-Altar Valley, Ariz. 163-165, pi. 41 discharge of, at Bonner Springs, Kans Gila and San Simon Valley, Ariz. 183-184, pi. 45 39,46, pi. 13 of Ogden Valley, Utah.. 101-103 at Kansas City, Kans. ..__ 39 Lohman, K. E., diatoms identified by.. 193-200 at Lecompton, Kans__... ____ 39,52 Lohr, E. W., analyses by...__... 160-161,179-180 at Ogden, Kans______... 39,45, pi. 13 Chemical character of the ground water in at Topeka, Kans_____ 39,46, pis. 11,13 the valley of Gila River and San at Wamego, Kans. 39,46, pi. 13 Simon Creek, Graham County, near Junction City, Kans.______39 Ariz______.__. _____ 217-222 near Manhattan, Kans______39 Los Angeles River, discharge of, at Los An­ early floods on ...... __ 49 geles. . 87 flood on, damage by______40-44 Lynch, Walter, with Livingston, Penn, Meth­ Kansas River Basin. See Republican River- ods of locating salt-water leaks in Kansas River Basin. water wells____ 1-20, pis. 1-9 288 INDEX

Page Page M Pickens Canyon, Calif., debris in, composition oL._ . . 88-89, pl.30 Manhattan, Kans., Big Blue River at, dis­ debris in, measurement of..__ __ 93 charge of.______52 movement of .______...__ 71-74, Kansas River near, discharge of_____ 39 77-80,86-88, pis. 16-17,19-26,28-30 Mansfield, W. C., fossils identified hy____ 199 source of... . 93-96,pis. 17,21-22,32-33 Max, Nehr., Repuhlican River at, discharge discharge of ____ .______66-68,83 Of.______._____...... _ 45 Pickna well. See Winter Haven, Tex., well Medicine Creek, Nebr., flood on, damage by.. 40-44 near. Meinzer, 0. E., quoted______209 Metainorphic rocks, occurrence of, in Qila and Final schist, occurrence of, in Qila and San San Simon Valley, Ariz_____ 195 Simon Valley, Ariz______195 Methods of locating salt-water leaks in wells.. 4-19, Pine View Reservoir, Ogden Valley, Utah, pis. 1-9 capacity of__...... _..... 142-143 Mining, Avra-Altar Valley, Ariz ..___ 171 probable effect of, on artesian reservoir. 143-144 Monthly Weather Review quoted.__ 225-226,280 Pinto Creek, discharge of, near Del Rio, Tex._ 284 Mottled enamel, cause of, in teeth______220 Pleistocene time, events of, in Qila and San Simon Valley, Ariz_____... 188-189 N Pleistocene(i) terrace gravel, character and distribution of, in Qila and San Newspapers quoted ______41,42 Simon Valley, Ariz_... 200 Niles, Kans., Solomon River at, discharge of. 47,52 Population, Avra-Altar Valley, Ariz. 170 North Llano River, altitude and descent of 243 Qila and San Simon Valley, Ariz._. __ 186 discharge of, near Junction, Tex. 245,246,263,283 Pozo Verde Mountains, Avra-Altar Valley, Nueces River, altitude and descent of.___ 247 Ariz., geologic character of- 171-172 discharge of, at Cotulla, Tex. 248,249,270-271,284 Pre-Cambrian rocks, occurrence of, in Avra- at Laguna, Tex 248,249,268-269,284 Altar Valley, Ariz ...... 171-172 near Three Rivers, Tex. 248,249,272-273,284 occurrence of, in Gila and San Simon Val­ near Uvalde, Tex...... 248,249,269-270,284 ley, Ariz .._ -.. .. 195 flood on.... . 236-237, 245, 246-249, pis. 57, 61 Previous investigations, in Avra-Altar Val­ ley, Ariz______.__ 165 in Gila and San Simon Valley, Ariz___ 185 Ogden, Kans., Kansas River at, discharge of. 39, in Ogden Valley, Utah..__._...._ 103-104 45, pi. 13 Pumping method of locating salt-water leaks Ogden, Utah, City of, cooperation with__ 99-161 in wells, operation of . . 4-8, pi. 1 Ogden River, Utah, analysis of water from.. 160-161 discharge of..__.______114-118, pi. 39 Q Middle Fork of, analyses of water from. 160-161 discharge of. .. __ 112-113 Quaternary alluvium, character and distribu­ North Fork of, analyses of water from.. 160-161 tion of, in Qila and San Simon discharge of______114, pi. 39 Valley, Ariz__...... 200-201, pi. 46 South Fork of, analyses of water from.. 160-161 wells in, in Gila and San Simon Valley, discharge of.._...... Ill, 113, pis. 37-38 Ariz.. 207-208 Ogden Valley, Utah, section in______109 Quaternary rocks, occurrence of, in Avra- Oro Blanco Mountains, Ariz., geologic char­ Altar Valley, Ariz. .. 172 acter of...... 171-172 occurrence of, in Gila and San Simon Val­ ley, Ariz.. . 195 Quinlan Mountains, Ariz., geologic character of.. . 171 Paint Creek, discharge of, near Telegraph, Tex_...... 245,283 R Paleozoic rocks, occurrence of, in Avra-Altar Valley, Ariz...... 172 Rainfall, Avra-Altar Valley, Ariz 168 Pedernales River, discharge of, near Spice- Gila River and San Simon Creek Valley, wood, Tex-_.__ 241,266,283 Ariz .. . . 187 Pediments, in Avra-Altar Valley, Ariz., geo­ La Canada Valley 58-59,60-65 logic character of______166,172-173 Ogden Valley, Utah... 105-106, pi. 35 in Avra-Altar Valley, Ariz., wells in__ 174-175, Republican River-Kansas River Basin 24-29, pi. 41 pi. 10 in Gila Valley, features of____ 192-193, pi. 49 Texas 233-234, 237-239,244,251,276-278, pi. 58 Peloncillo Mountains, Ariz., geologic character Randolph, Kans., Big Blue River at, dis­ of__ ._ 195 charge of. . 48 Permeability coefficient, definition of____ 120 Red Cloud, Nebr., Republican River at-..-, pi. 12 Peterson, J. Q., with Troxell, H. C., Flood in Republican River at Cambridge, Nebr. pi. 12 La Canada Valley, Calif., January at Red Cloud, Nebr . pi. 12 1,1934...... ____ 53-98, pis. 16-34 at Wakefield, Kans . pi. 14 INDEX 289

Page Republican River discharge of . 32-33,37-39, pi. 13 Scandia, Kans., Republican River at, flood discharge of, at Bloomington, Nebr__ 45 discharge of .... . 45, pis. 13,14 at Bostwick, Nebr.. 49 Schwennesen, A. T., quoted_ ... 191 at Clay Center, Kans______45, pi. 13 Seco Creek, discharge of, near D'Hanis, Tex.. 284 at Culbertson, Nebr. 45, pi. 11 earlier floods on_.....__ __ 236 at Junction City, Kans __ 52 flood on, discharge from.. . 234-236 at Mas, Nebr.- ______45 general features of-- 232-233 at Scandia, Kans..___.__ 45, pis. 13,14 rainfall causing ____.....__ 233-234 near Hardy, Nebr.______45, pi. 13 Second-feet, definition of ___ -- 227 near Superior, Nebr. . .. 49-50 Second-feet per square mile, definition of 227 earlier floods on_ .. __..... 49-51 Sedimentary rocks, formations of, in Gila and flood on, damage by...__ __..... 40-44 San Simon Valley, Ariz...... 196-205 crests of______33-36, pis. 11-14 Sediments, character and thickness of, in Og- North Fork of, discharge of_--___.-- 46 den Valley, Utah... .__.... 107-110 South Fork of, discharge of- ...- 32-34,37-39 Sespe Creek, Calif., discharge of..---__-. 97 Republican River-Kansas River Basin, gaging Shields Canyon, Calif., crest discharge of 67,82 stations in.._____.___ 44, pi. 15 Sierrita Mountains, Ariz., geologic character gaging stations in, daily discharge at.. 46-48,52 Of- . 171,172, pis. 43-44 previous floods in______49-51 Silverbell Mountains, Ariz., geologic charac­ Indian traditions regarding_____ 50-51 ter of __- 172 rainfall in______24-29, pi. 10 Smith, H. V., and Smith, M. C., quoted 220 topography of... ______29-31 Smithville, Tes., Colorado River at, discharge Rio Qrande, discharge of, at Eagle Pass, Tes. 284 of...._...... __ 241,242,260-261,283 discharge of, near Del Rio, Tes_____ 284 Smoky Hill River, discharge of, at Ellswortb, Rio Qrande Basin, flood in_...._._.__ 257 Kans_._.______47,52 Rio Hondo, discharge of, near Montebello, discharge of, at Enterprise, Kans 47 Calif- . 97 at Lindsborg, Kans__ 47 Roberts Canyon, Calif., debris in, composition Snyder Hill, Ariz., geologic character of. 172 of __....__... 88-89 Soil, conservation of, in Gila Valley, Ariz 194 Rogers Creek, Calif., debris in, composition erosion of, relation of, to rainfall 93-94, of.. .. 88-S9 pis. 31-32, 34 discharge of______.....____.. 97 features of, in La Canada Valley, Calif. 58 Roswell, N. Mes., wells near, study of.-__ 8 Soldier Creek, discharge of, at Topeka, Kans. _ 48 Rothe, Josie, quoted______232-233 Solomon River, discharge of, at Beloit, Kans....__._.__ __ 47, pi. 11 discharge of, at Niles, Kans ..._ 47,52 Solomonsville, Ariz., Gila River near.... 207, pi. 47 Saline River, discharge of, at Tescott, Kans.. 47 San Simon Creek near______pi. 48 discharge of, near Salina, Kans._____ 52 South Llano River, altitude and descent of-... 243 near Wilson, Kans____._____.. 47 discharge of, near Telegraph, Tex 245,283 Salt-water leaks in wells, electrical-conduc­ Spicer, H. C., depth-temperature study of tivity method of locating.. 12-19, pis. 3-9 wells by.__ _..___ 217 pumping method of locating..____ 4-8, pi. 1 Spicewood, Tes., Pedernales River near, dis­ sampler method of locating_._ 10-12, pis. 3-4 charge of-_--___-- 266 San Antonio River, discharge of, near Falls Spiegel, J. B., with Follansbee, Robert, Flood City, Tes 267,283 San Felipe Creek, discharge of, near Del Rio, on Republican and Kansas Rivers, May and June 1935..-. 21-52, pis. 10-15 Tex- _ 284 Spring Branch, Tes., Guadalupe River near, San Gabriel River, discharge of, at Pico, Calif. 97 discharge of . 266-267 San Jose Creek, Calif., discharge of._____ 97 Springs, in Avra-Altar Valley, Ariz 172 -San Luis Mountains, Ariz., geologic character in Gila and San Simon Valley, Ariz... 214-217, of ...... 171-172 pis. 46, 52, 53 San Saba, Tex., Colorado River near, dis­ in Gila and San Simon Valley, Ariz., charge of______... 258-259 water from, analyses of- 222 San Simon Creek, Ariz., age of._____ 189, pi. 48 in Ogden Valley, Utah... 115,136,137,139 San Simon Valley, Ariz., features of___ 188-190, pis. 47-48 Stage-discharge relation, definition of_ 227 Sanitation, emergency measures for_____ 43-44 Staked Plains of Tesas, features of____ 228 Santa Ana River, Calif., debris in, composi­ Stranger Creek near Tonganosie, Kans., dis­ tion of . 88-89 charge of--____ _ 48 Santa Paula Creek, Calif., crest discharge of 97 Stream flow, in Ogden Valley, Utah_... 144-146 Santa Teresa Mountains, Ariz., geologic charac­ Structure, features of, in Gila and San Simon ter of.______.___....__ 195 Valley, Ariz. _. 194-195 Sarasota County, Fla., wells in, study of__ 10, Superior, Nebr., Republican River near, dis­ 18,19, pis. 3-6, 8 charge of_._ . 49-50 Sawpit Creek, Calif., debris in, composition Surface water, analyses of, from Ogden Valley, of...... ____... 88-89 Utah...... 160-161 290 INDEX

Page Pagt Surface water, discharge measurements of, in Velocity method of locating salt-water leaks in Gila and San Simon Valley, Ariz. 207 wells, operation of______8-10, pi. 2 in Odgen Valley, Utah.. 111-118, pis. 37-39 Verdugo Canyon, discharge of, at Wabasso irrigation with, in Gila and San Simon Way, Calif.. .. 67-68- Valley, Ariz..___..... 206-207, pi. 47 Verdugo Mountains, Calif., run-off in..... 98, pi. 34 Sycamore Creek, discharge of, near Del Rio, Tex ...... 284 W Sycamore Creek Basin, flood in______257 Wabasso Way, Calif., Verdugo Canyon at, discharge of______.___.... 67-68- T Wakarusa River, discharge of, near Lawrence, Tanque, Ariz., San Simon Creek near__ pis. 47-48 Kans______...___ 48- Taylor, G. H., with Leggette, R. M., Geology Wakefleld, Kans., Republican River at___ pi. 14 and ground-water resources of Wamego, Kans., -Kansas River at, discharge Ogden Valley, Utah.. 99-161, pis. 35-40 of...... 39, 46, pi. 13 Telegraph, Tex., Paint Creek near, discharge Water, history of use of, in Ogden Valley, of...... 245,283 Utah...... 10$ South Llano River near, discharge of_ 245,283 municipal supplies of, in Gila and San Terms, definition of..______227 Simon Valley, Ariz______206 Tertiary rocks, occurrence of, in Avra-Altar quality of, in Avra-Altar Valley, Ariz.... 177-180- Valley, Ariz______172, pi. 42 in Gila and San Simon Valley, Ariz. 217-222 occurrence of, in Gila and San Simon in Ogden Valley, Utah...... 142,160-161 Valley, Ariz______195 uses of, in Gila and San Simon Valley, Tertiary time, events of, in Gila and San Ariz...... 205- Simon Valley, Ariz...... _.. 188 Water level, in Ogden Valley, Utah, fluctua­ Tescott, Kans., Saline River at, discharge of_ 47 tions of______126-131 Texas Board of Water Engineers, cooperation In Ogden Valley, Utah, records of 154-1591 with.______1-20, 223-284 Water spreading, in Ogden Valley, Utah, pos­ Three Rivers, Tex., Nueces River near, dis­ sibilities of. 135-136- charge of ___ 248, 249, 272-273,284 Waterman Mountains, Ariz., geologic char­ Tonganoxie, Kans., Stranger Creek near, dis­ acter of______.. 172 charge of...... _..__ 48 Waterville, Kans., Little Blue River at, dis­ Topeka, Kans., Kansas River at, discharge charge of..___ __ . 48- of..______39, 46, pi. 13 Wells, construction of, to avoid contamination Soldier Creek at, discharge of______48 by salt water_. .. 19-201 Topography, Gila and San Simon Valley, deep, in Gila and San Simon Valley, Ariz______. 183-184, pi. 45 Ariz...... 212-214, pi. 5* La Canada Valley.._____ 56-58, pis. 16-18 depth-temperature relations in.. 217 Republican River-Kansas River Basin__ 29-31 in Avra-Altar Valley, Ariz. _ 174-177, pi. 41 Texas_____._____.__ 228-229, pi. 55 water from, analyses of__ 179-180* Transportation and settlements, Avra-Altar in Gila and San Simon Valley, Ariz., logs Valley, Ariz_____..___ 169-170 of .. . 202-20* Gila and San Simon Valley, Ariz____ 185-186 records of._____ .... 222 (Inserts) Troxell, H. C., and Peterson, J. Q., Flood in water from, analyses of. 222" La Canada Valley, Calif., Jan. l, in Gila conglomerate, Gila and San Simon 1934______53-98, pis. 16-34 Valley, Ariz. ..____ 208-212, pi. 46 Tucson Mountains, Ariz., geologic character in Ogden Valley, Utah, logs of.. pi. 40- of 172 records of...... 122-131,146-153, pis. 37-38 Turnbull Mountains, Ariz., geologic character water from, analyses of. 160-161 of __.. 195 in Quaternary alluvium, Gila and San Twin Falls South Side project, Idaho, wells in, Simon Valley, Ariz...... 207-208, pi. 46- study of __ __._____ 8 locating salt-water leaks in 1-20, pis. 1-9 observation, in Ogden Valley, Utah. 122-123, pis. U 36-3» salt-water leaks in, areas studied 3 United States Army, Chief of Engineers, West Nueces River, altitude and descent of 250- quoted______49 flood on._....__..... 236-237,247,249-256 United States Weather Bureau quoted___ 276 discharge of, near Brackettville, Tex__252-256, Uvalde, Tex., Nueces River near, discharge 284, pi. 62- Of...... __...... 248, 249,269-270,284 near Cline, Tex___ . 284 Whiteoak Bayou, discharge of, at Houston, Tex.-.._...... _ _ - 283- Valley Falls, Kans., Delaware River at, dis­ Whitsett, Tex., Atascosa River at, discharge charge of-______.__ 48 Of _._.___.__ 275-276,284 Vegetation, Avra-Altar Valley, Ariz.. 169, pis. 43-44 Wilson, Kans., Saline River near, discharge of. 4T Gila and San Simon Valley, Ariz__ .. 187 Winter Garden area, Texas, wells in, study La Canada Valley______59 of__.._- 5,9-10,13,14,15,19, pis. 3-» Ogden Valley, Utah..____._____ 106 Winter Haven, Tex., well near, study of.. 5-6,16, IT