Compilation of instream flow & estuary inflow statistics for the Sabine and Neches River Basins and Sabine Lake April 2010
FLOWS ATLAS Compilation of instream flow & estuary inflow statistics for the Sabine and Neches River Basins and Sabine Lake Analyses and basic text prepared by J.F. Trungale Engineering and Science, Austin, TX for the National Wildlife Federation. This project made possible with financial support from the Houston Endowment, the Meadows Foundation, and the Cynthia and George Mitchell Foundation. ii
Table of Contents List of Tables... iv List of Figures... vi... 1 1.0 Background... 1 2.0 Magnitude measures at River Sites... 3 3.0 Magnitude measures, Estuary... 3 4.0 Duration measures at River Sites, Context for BBEST-recommendations... 4 5.0 Examples... 5 iii
List of Tables Table 1 - River sites identified by the Sabine/Neches BBEST.... 1 Table 2-1 Monthly Percentiles at Big Sandy Creek near Big Sandy.... 6 Table 2-2 Monthly Percentiles at Sabine River near Gladewater.... 7 Table 2-3 Monthly Percentiles at Sabine River near Beckville.... 8 Table 2-4 Monthly Percentiles at Sabine River near Bon Wier.... 9 Table 2-5 Monthly Percentiles at Big Cow Creek near Newton.... 10 Table 2-6 Monthly Percentiles at Sabine River near Ruliff.... 11 Table 2-7 Monthly Percentiles at Neches River near Neches.... 12 Table 2-8 Monthly Percentiles at Neches River near Rockland.... 13 Table 2-9 Monthly Percentiles at Angelina River near Alto.... 14 Table 2-10 Monthly Percentiles at Attoyac Bayou near Chireno.... 15 Table 2-11 Monthly Percentiles at Neches River at Evadale.... 16 Table 2-12 Monthly Percentiles at Village Creek near Kountze.... 17 Table 3-1 Seasonal Percentiles at Big Sandy Creek near Big Sandy.... 18 Table 3-2 Seasonal Percentiles at Sabine River near Gladewater... 19 Table 3-3 Seasonal Percentiles at Sabine River near Beckville.... 20 Table 3-4 Seasonal Percentiles at Sabine River near Bon Wier.... 21 Table 3-5 Seasonal Percentiles at Big Cow Creek near Newton.... 22 Table 3-6 Seasonal Percentiles at Sabine River near Ruliff.... 23 Table 3-7 Seasonal Percentiles at Neches River near Neches... 24 Table 3-8 Seasonal Percentiles at Neches River near Rockland.... 25 Table 3-9 Seasonal Percentiles at Angelina River near Alto... 26 Table 3-10 Seasonal Percentiles at Attoyac Bayou near Chireno.... 27 Table 3-11 Seasonal Percentiles at Neches River at Evadale.... 28 Table 3-12 Seasonal Percentiles at Village Creek near Kountze.... 29 Table 4-1 Estuary Inflow Percentiles for Sabine Lake.... 30 Table 4-2 Estuary Inflow Percentiles for Sabine Lake (Sabine Basin only).... 31 Table 4-3 Estuary Inflow Percentiles for Sabine Lake (Neches Basin only).... 32 Table 4-4 Estuary Inflow Percentiles for Sabine Lake (Coastal Basins only).... 33 Table 5-1 Duration of instream subsistence flow at Big Sandy Creek near Big Sandy.... 34 Table 5-2 Duration of instream subsistence flow at Sabine River near Gladewater.... 34 Table 5-3 Duration of instream subsistence flow at Sabine River near Beckville.... 35 Table 5-4 Duration of instream subsistence flow at Sabine River near Bon Wier.... 35 Table 5-5 Duration of instream subsistence flow at Big Cow Creek near Newton.... 36 Table 5-6 Duration of instream subsistence flow at Sabine River near Ruliff.... 36 Table 5-7 Duration of instream subsistence flow at Neches River near Neches.... 37 Table 5-8 Duration of instream subsistence flow at Neches River near Rockland.... 37 Table 5-9 Duration of instream subsistence flow at Angelina River near Alto.... 38 Table 5-10 Duration of instream subsistence flow at Attoyac Bayou near Chireno.... 38 iv
Table 5-11 Duration of instream subsistence flow at Neches River at Evadale.... 39 Table 5-12 Duration of instream subsistence flow at Village Creek near Kountze.... 39 v
List of Figures Figure 1 Map of sites in the Sabine and Neches River basins.... 2 Figure 2 Example of seasonal percentiles for a riverine site.... 5 Figure 3 Example of percentiles for a freshwater inflow site.... 5 vi
1.0 Background The purpose of this report is to document various calculations to help inform the development of instream flow and estuary inflow regimes and flow standards for the Senate Bill 3 (SB3) process in Texas. This Atlas presents flow statistics that we believe have great utility for SB3 stakeholders and scientists, as well as the public and covers the Sabine and Neches River basins and Sabine Lake estuary. Although there are an abundance of potential flow and inflow statistics that can be tabulated, this document presents some basic magnitude and duration measures. The magnitude measures document a full range of flow percentiles for river sites and for bay inflows in the basins while duration measures only pertain to characterization of very low flows at river sites. Table 1 lists the river sites identified for analysis by the Bay Basin Expert Science Team- (BBEST) for the Sabine and Neches Rivers. Table 1 - River sites identified by the Sabine/Neches BBEST. Sabine Neches Basins USGS Gauge No. Location 08019500 Big Sandy Creek near Big Sandy 08020000 Sabine River near Gladewater 08022040 Sabine Rv near Beckville 08028500 Sabine River near Bon Wier 08029500 Big Cow Creek near Newton 08030500 Sabine River near Ruliff 08030800 Attoyac Bayou near Chireno 08032000 Neches River near Neches 08033500 Neches Rv near Rockland 08036500 Angelina River near Alto 08041000 Neches River at Evadale 08041500 Village Creek near Kountze 1
Figure 1 Map of sites in the Sabine and Neches River basins. 2
2.0 Magnitude measures at River Sites magnitude is the most common measurement used to characterize environmental flows. Other parameters include duration, frequency, timing, rate of change, range of variability and volume. While these other parameters apply to specific components of the flow regime (which typically includes subsistence flows, base flows, high flow pulses and overbank flows), the magnitude measure is important for all of the flow components. magnitude is the primary parameter used to define base or low flow requirements. Base flows are the dominant flow condition in most rivers. These low-flow levels in a river impose a fundamental constraint on a river's aquatic communities because they determine the amount of aquatic habitat (e.g. runs, riffles, pools) and this has a strong influence on the diversity and number of organisms that can live in the river. An environmental flow regime may include base flows with both intra- and inter-annual variability. Aquatic organisms have adapted life history traits that respond to seasonal changes in flows and year-to-year variability is essential in order to balance the distinct habitat requirements of various species, guilds, and assemblages. Each of the sites listed in Table 1 was analyzed to determine the percentile flows, measured as a flow rate in units of cubic feet per second (cfs), in two ways. First is the most basic approach of using regular monthly categories. For instance, for any given site, all the flows that occurred during the month of January through a certain period of record were lumped together and flow percentiles (e.g. the 5 th, 10 th, percentiles) calculated for that month. The magnitude measure results of the monthly approach are in the Table series 2 (i.e. 2-1, 2-2, ). Because the BBESTs recommended flows on a seasonal basis, flow magnitude percentiles by season also are presented. Consistent with the approach used to define the recommendations, all of the daily flows in a season, as defined by the BBEST, were lumped together and statistics calculated based on this population. The results of the seasonal approach are presented in Table series 3. 3.0 Magnitude measures, Estuary The magnitude of flow is also an important consideration in the development of inflow recommendations for estuaries. The inflow magnitude is a significant factor regulating salinity conditions in the estuary especially during times of average to low inflow conditions. Higher flows are important in that they are most responsible for the transportation of nutrients and sediments into the estuary. While river flows are typically measured in terms of instantaneous flow rates, estuarine inflows are less sensitive to instantaneous fluctuations in flow and thus are generally evaluated in terms of monthly, seasonal, or even annual estimates. Thus Table series 3
4 includes volume percentiles for estuary inflows in units of acre feet per month, season, and year. 4.0 Duration measures at River Sites, Context for BBESTrecommendations In additional to flow magnitude, extended durations of low flow conditions can be an important factor affecting a sound ecological environment. Low flows may result in disconnected pools, along with confined and crowded habitat conditions, which may have a significant effect on predator-prey interactions and increase competition for scarce resources. Low flows also have direct relationships to degraded water quality conditions including increased temperature and decreased dissolved oxygen conditions. While most native species are adapted to natural drought conditions characteristic of some Texas summers, an increase of drought durations may lead to stress beyond the tolerance of some species. Series 5 tables present results of an analysis of the duration, in number of days, for which flows remain below the subsistence level recommended by the BBEST. These tables include results for different time periods: the entire period of record for which gage data are available, an earlier subset intended to reflect less altered flow conditions, and a more recent period reflective of current water management practices. 4
5.0 Examples The percentile statistics presented in the series 2, 3, and 4 tables are intended to provide some context from which to consider flow recommendations including those developed by the BBESTs. Percentile statistics are most easily explained with an example. Figure 2, is an example portion of a typical series 3 table of seasonal percentiles for a river site. In this case, the 4th percentile flow in the Spring season is reported as 366 cfs. This means that for all the days that occurred in the spring months during that period of record (1924-2008), on just 4 percent of those days flow was less than 366 cfs. The converse is also true, that on 96 percent of the days flow was greater than 366 cfs. The series 2 tables with monthly statistics can be understood the same way. Start January, 1924 End December, 2008 season percentile Winter Spring Summer Fall level Dec-Feb Mar-Jun Jul-Sep Oct-Nov min 98 66 8 28 1% 149 182 54 85 2% 175 260 66 96 3% 211 305 80 106 4% 248 366 95 116 5% 292 423 105 130 10% 441 680 173 208 15% 586 871 259 295 Figure 2 Example of seasonal percentiles for a riverine site. Figure 3 shows an example portion of a typical freshwater inflow table, as presented in the series 4 tables. The percentiles reported Start End January, 1941 December, 2005 percentile annual seaon Spring month level Mar-May Mar Apr May 0% 1,871 399 74 136 118 * * * * * * * * * * * * * * * * * * 40% 8,441 2,443 598 547 847 45% 10,731 2,748 684 619 997 50% 11,163 3,487 771 662 1,312 55% 11,571 3,614 857 710 1,385 60% 12,705 3,939 991 798 1,515 65% 13,433 4,103 1,329 987 1,678 * * * * * * * * * * * * * * * * * * 100% 21,960 9,196 4,456 5,290 4,571 Figure 3 Example of percentiles for a freshwater inflow site. in the freshwater inflow tables are somewhat different from the statistics presented in the river tables (Series 2 and 3). The river statistics present results based on different subsets of historical data for individual days (grouped by month or by season). However, the freshwater inflow tables include seasonal and annual totals, grouped and sorted by those totals. Thus, for example, from Figure 3, the 40 th percentile total inflow volume for the Spring season (sum of March, April and May volumes) is 2,443 (units of 1000 acre-feet). Thus inflows were less than or equal to 2,443,000 acft, in 40 percent of the Springs for the period and greater than this level in 60 percent of the Springs. 5
Table 2-1 Monthly Percentiles at Big Sandy Creek near Big Sandy. Statistic: Percentile flow magnitudes (cfs), by month. Site: Big Sandy Creek near Big Sandy, TX (USGS guage no. 08019500) Start January, 1940 End December, 2007 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 20 31 32 19 10 5 4 1 0 3 1 2 1% 24 38 38 26 16 8 7 4 1 7 3 12 2% 29 46 42 30 19 10 7 4 4 8 11 18 3% 31 50 46 34 21 12 8 5 5 9 16 20 4% 34 52 50 36 24 13 9 6 7 10 17 24 5% 36 55 53 39 26 14 9 6 7 12 18 26 10% 50 72 71 49 35 19 12 8 10 14 22 34 15% 61 84 79 60 44 24 15 10 12 15 28 41 20% 69 99 95 72 53 29 17 12 13 17 33 50 25% 78 112 119 83 63 35 20 13 15 19 38 59 30% 88 125 134 98 75 41 23 15 17 21 42 69 35% 99 137 147 109 90 47 25 16 19 23 46 80 40% 112 150 159 122 105 55 27 18 20 25 50 94 45% 127 163 176 139 120 64 30 19 23 28 55 109 50% 145 177 194 154 137 73 33 21 26 31 61 125 55% 164 192 215 173 157 82 37 24 28 35 68 140 60% 185 210 240 200 176 95 42 26 30 39 75 159 65% 209 235 269 224 202 109 48 29 33 44 87 179 70% 238 266 309 254 233 126 56 31 37 49 102 207 75% 273 310 364 291 270 154 69 34 42 55 124 236 80% 321 362 425 340 328 195 84 39 51 67 155 280 85% 410 458 522 436 433 275 109 44 68 83 189 355 90% 544 636 682 611 623 408 170 59 97 118 258 509 95% 840 920 981 969 1,103 661 300 95 151 194 512 777 96% 936 1,020 1,090 1,114 1,247 740 412 115 172 232 600 869 97% 1,030 1,144 1,210 1,348 1,470 868 513 142 201 299 713 1,068 98% 1,199 1,330 1,429 1,916 1,946 1,010 698 206 270 410 834 1,360 99% 1,499 1,876 1,826 2,930 2,606 1,408 1,027 255 377 665 1,237 1,808 max 3,420 5,310 17,900 11,400 6,540 6,000 4,000 776 1,640 3,750 5,320 5,530 6
Table 2-2 Monthly Percentiles at Sabine River near Gladewater. Statistic: Percentile flow magnitudes (cfs), by month. Site: Sabine River near Gladewater, TX (USGS guage no. 08020000) Start January, 1933 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 45 61 137 60 32 22 7 6 8 7 12 33 1% 90 152 173 115 68 28 13 10 9 11 25 62 2% 111 180 201 138 84 32 16 11 10 12 29 73 3% 120 227 222 151 99 41 18 12 11 16 36 81 4% 138 253 238 163 111 51 24 14 12 19 40 88 5% 158 273 257 172 122 56 24 14 14 21 44 96 10% 232 371 357 245 192 84 36 23 21 32 68 129 15% 291 440 453 338 256 115 48 28 29 41 94 178 20% 345 544 559 438 322 152 60 34 37 49 113 229 25% 414 665 682 544 391 197 74 39 45 61 140 265 30% 488 766 836 660 502 265 90 45 52 75 164 324 35% 573 862 1,020 800 679 352 108 52 62 86 196 392 40% 706 1,040 1,230 961 866 445 125 62 74 97 231 449 45% 866 1,250 1,460 1,256 1,120 547 146 74 87 112 273 538 50% 1,030 1,500 1,865 1,510 1,500 669 175 86 96 130 325 678 55% 1,280 1,820 2,260 1,845 2,000 839 212 101 107 150 392 867 60% 1,550 2,186 2,760 2,280 2,550 1,074 256 115 124 178 500 1,100 65% 1,910 2,600 3,340 2,760 3,140 1,410 322 128 142 218 636 1,460 70% 2,475 3,004 3,900 3,283 3,975 1,876 414 146 166 268 852 1,895 75% 3,233 3,600 4,753 3,923 4,705 2,453 519 169 216 327 1,143 2,403 80% 4,290 4,238 5,650 4,880 5,760 3,332 711 208 306 456 1,560 2,970 85% 5,268 4,911 6,510 6,080 6,838 4,473 1,040 269 448 683 2,110 3,878 90% 6,210 5,764 7,390 7,190 9,255 5,560 2,030 400 685 1,320 3,120 5,655 95% 8,110 7,911 9,920 8,981 14,800 7,791 3,510 892 1,311 2,850 5,311 8,323 96% 8,926 8,906 10,880 10,000 16,380 8,849 4,374 1,144 1,498 3,430 5,980 9,370 97% 10,035 11,200 12,600 12,426 19,170 10,600 5,574 1,530 1,780 4,047 6,730 11,235 98% 11,290 13,932 14,800 15,842 23,760 14,000 6,618 1,870 2,064 4,579 7,939 13,600 99% 14,345 17,970 16,900 23,621 36,945 20,263 8,180 2,790 3,256 5,709 9,521 18,545 max 40,600 34,600 32,900 133,000 57,400 64,500 19,200 5,690 4,670 8,410 44,500 38,900 7
Table 2-3 Monthly Percentiles at Sabine River near Beckville. Statistic: Percentile flow magnitudes (cfs), by month. Site: Sabine Rv near Beckville, TX (USGS guage no. 08022040) Start January, 1939 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 66 220 252 166 50 27 7 2 8 7 15 60 1% 116 277 310 223 128 47 21 12 10 12 37 76 2% 154 307 345 242 149 59 24 15 11 14 45 94 3% 172 347 376 262 177 69 28 18 13 20 50 107 4% 193 366 408 296 206 82 31 20 15 24 62 117 5% 217 413 424 323 231 89 35 22 18 26 69 127 10% 323 597 564 424 354 140 60 36 32 48 103 196 15% 431 727 767 575 468 204 84 47 46 59 134 259 20% 547 914 950 760 613 289 118 57 60 77 166 342 25% 669 1,143 1,240 920 780 418 149 72 76 92 202 421 30% 809 1,340 1,480 1,107 1,000 535 177 85 95 110 249 545 35% 950 1,650 1,760 1,340 1,262 678 205 100 112 128 310 646 40% 1,136 1,930 2,080 1,650 1,546 814 244 115 128 144 378 818 45% 1,440 2,220 2,500 2,000 2,060 1,010 291 132 144 166 451 1,021 50% 1,730 2,700 3,150 2,350 2,590 1,255 336 150 160 194 555 1,240 55% 2,120 3,234 3,730 2,765 3,149 1,570 394 170 182 236 660 1,470 60% 2,604 3,770 4,350 3,320 3,864 1,924 472 191 215 285 798 1,894 65% 3,237 4,251 5,010 3,934 4,830 2,484 586 219 250 343 1,044 2,440 70% 3,990 4,799 5,643 4,550 5,803 3,063 745 258 305 417 1,333 3,140 75% 5,003 5,480 6,360 5,318 6,600 3,933 956 309 391 535 1,780 3,780 80% 6,072 6,250 7,130 6,420 7,762 5,002 1,252 378 520 736 2,444 4,482 85% 7,586 7,395 8,190 7,733 9,527 6,092 2,033 475 745 1,107 3,320 5,800 90% 9,300 8,579 9,413 9,217 11,900 7,920 3,032 733 1,171 1,990 4,701 7,882 95% 11,200 10,900 12,000 11,900 15,500 11,005 5,496 1,620 1,820 3,461 6,774 10,900 96% 11,500 11,200 12,724 12,400 17,824 12,200 6,062 1,862 2,051 4,122 7,530 11,700 97% 11,893 11,869 13,886 13,500 20,086 14,803 7,427 2,120 2,321 4,668 8,121 12,400 98% 12,562 13,292 17,224 15,206 24,448 17,300 8,757 2,689 2,951 5,242 9,771 13,362 99% 13,900 16,815 21,962 23,518 35,400 23,503 11,524 4,342 4,591 6,036 12,100 15,193 max 33,700 32,000 39,000 120,000 69,400 48,600 17,200 10,000 6,360 8,600 35,400 36,400 8
Table 2-4 Monthly Percentiles at Sabine River near Bon Wier. Statistic: Percentile flow magnitudes (cfs), by month. Site: Sabine River near Bon Wier, TX (USGS guage no. 08028500) Start January, 1924 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 479 528 554 326 362 251 246 172 160 143 134 195 1% 615 691 792 590 598 483 326 197 184 182 200 372 2% 695 789 896 651 764 528 390 232 210 199 242 483 3% 760 904 981 770 850 597 440 257 223 218 270 551 4% 822 1,001 1,060 844 913 666 480 271 237 234 290 602 5% 875 1,131 1,170 907 958 693 524 299 250 245 320 636 10% 1,190 1,760 1,640 1,160 1,290 920 685 408 334 309 423 796 15% 1,520 2,340 2,280 1,430 1,721 1,120 805 505 403 365 513 930 20% 1,890 3,124 3,116 1,938 2,090 1,400 912 595 500 439 580 1,078 25% 2,425 4,300 4,255 2,500 2,600 1,720 1,060 716 611 490 660 1,240 30% 3,210 5,573 5,466 3,300 3,000 2,080 1,250 850 720 547 766 1,450 35% 4,250 6,770 6,860 4,000 3,480 2,552 1,540 998 845 624 878 1,709 40% 5,292 7,824 8,200 5,040 4,074 2,910 1,890 1,146 973 690 1,030 2,050 45% 6,880 8,960 9,380 6,181 4,910 3,250 2,250 1,403 1,090 785 1,130 2,573 50% 8,380 10,300 10,500 7,620 5,930 3,715 2,690 1,790 1,250 870 1,250 3,200 55% 9,940 11,500 12,100 8,660 7,044 4,220 3,160 2,227 1,440 955 1,400 3,970 60% 11,800 12,800 14,200 10,100 8,288 4,704 3,788 2,574 1,720 1,040 1,600 5,200 65% 13,700 14,700 15,500 12,100 9,731 5,417 4,260 3,210 2,059 1,140 1,869 6,542 70% 15,600 15,800 16,200 14,200 11,580 6,393 4,758 3,988 2,653 1,298 2,380 7,970 75% 16,400 16,400 17,000 15,500 14,200 8,098 5,430 4,665 3,480 1,500 3,048 9,390 80% 17,800 17,500 18,200 16,620 16,300 9,920 5,954 5,402 4,210 1,772 4,062 11,600 85% 20,000 19,385 20,600 18,500 19,390 14,200 6,698 5,940 5,087 2,430 6,076 14,600 90% 23,300 22,100 23,900 23,010 24,720 18,200 7,776 6,620 6,235 4,088 8,141 17,200 95% 28,200 26,600 29,000 28,355 35,260 24,000 13,330 7,533 7,910 7,536 14,255 21,000 96% 29,264 28,884 30,264 29,516 37,864 26,200 14,800 7,730 8,410 8,431 15,404 22,300 97% 30,400 31,600 32,100 32,100 39,798 28,106 16,298 7,980 9,584 9,500 18,000 23,700 98% 32,100 37,186 34,596 36,900 44,860 31,002 19,664 9,436 11,502 10,732 21,604 27,800 99% 38,600 45,398 42,300 42,700 53,300 36,200 23,066 18,996 16,153 13,166 26,453 33,300 max 77,100 90,500 76,000 75,500 111,000 71,000 98,000 63,000 30,500 33,000 35,800 81,400 9
Table 2-5 Monthly Percentiles at Big Cow Creek near Newton. Statistic: Percentile flow magnitudes (cfs), by month. Site: Big Cow Creek near Newton, TX (USGS guage no. 08029500) Start January, 1953 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 28 30 35 21 19 12 10 12 13 14 17 24 1% 31 36 41 27 22 16 12 13 14 15 21 28 2% 34 40 43 30 25 17 15 15 16 17 23 31 3% 36 41 45 32 26 20 17 16 16 18 25 34 4% 38 43 45 34 28 20 18 18 17 18 26 35 5% 41 45 47 36 29 22 20 19 18 19 27 37 10% 48 54 54 43 34 27 24 22 22 22 31 41 15% 54 62 60 48 38 30 27 24 24 26 35 46 20% 59 68 65 52 42 32 29 27 27 28 38 50 25% 65 76 71 58 45 35 30 29 29 30 41 56 30% 73 84 78 63 48 39 32 30 31 32 44 64 35% 80 90 84 68 52 43 35 33 34 35 47 70 40% 87 97 93 72 56 47 38 35 36 38 51 77 45% 94 104 101 78 60 51 41 38 39 41 55 83 50% 104 112 110 83 66 55 45 42 41 43 60 90 55% 115 122 119 91 71 60 48 45 44 44 64 98 60% 126 135 126 97 80 65 52 49 46 48 70 109 65% 137 148 138 104 90 71 56 52 49 52 79 124 70% 154 165 150 115 100 79 64 56 53 55 90 137 75% 176 186 166 128 112 91 74 61 59 62 100 154 80% 207 228 192 148 132 110 85 67 67 72 120 184 85% 265 299 235 182 173 133 98 74 83 87 151 226 90% 375 411 310 269 253 184 122 88 98 117 225 321 95% 649 775 573 554 509 388 169 117 144 225 400 624 96% 737 844 665 632 633 471 198 127 172 278 477 763 97% 832 1,071 775 750 765 552 250 152 224 353 581 933 98% 1,070 1,265 894 1,000 918 789 326 187 391 542 749 1,043 99% 1,490 1,532 1,157 1,308 1,310 1,280 581 338 773 1,038 1,215 1,413 max 5,790 9,720 3,750 9,520 7,870 3,620 2,370 1,860 4,710 23,200 4,950 4,720 10
Table 2-6 Monthly Percentiles at Sabine River near Ruliff. Statistic: Percentile flow magnitudes (cfs), by month. Site: Sabine River near Ruliff, TX (USGS guage no. 08030500) Start January, 1925 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 949 1,080 1,140 641 570 431 417 315 270 270 292 296 1% 1,100 1,307 1,360 855 979 721 565 351 310 284 320 545 2% 1,180 1,400 1,440 1,110 1,140 873 637 405 340 299 362 779 3% 1,220 1,532 1,570 1,210 1,280 1,000 719 427 360 338 406 878 4% 1,260 1,759 1,650 1,308 1,370 1,080 765 450 379 359 450 968 5% 1,350 1,876 1,750 1,360 1,430 1,150 800 474 398 380 485 1,040 10% 1,946 2,660 2,586 1,750 1,913 1,440 1,000 632 478 470 665 1,300 15% 2,480 3,378 3,389 2,250 2,360 1,749 1,200 762 636 570 863 1,520 20% 2,876 4,338 4,510 3,100 2,780 2,100 1,440 905 805 695 975 1,680 25% 3,780 5,860 5,940 3,978 3,220 2,490 1,680 1,120 1,010 820 1,070 1,930 30% 4,900 7,762 7,590 4,900 3,670 2,880 2,049 1,350 1,170 910 1,187 2,220 35% 6,011 9,040 9,000 5,940 4,301 3,210 2,411 1,561 1,320 1,000 1,300 2,721 40% 7,470 10,600 10,200 7,096 5,022 3,580 2,810 1,920 1,470 1,100 1,430 3,160 45% 8,834 11,800 11,400 8,356 6,100 4,120 3,240 2,294 1,646 1,190 1,586 3,780 50% 10,600 13,200 12,800 9,600 7,155 4,635 3,695 2,660 1,860 1,295 1,760 4,660 55% 12,200 14,400 14,200 11,000 8,677 5,195 4,180 3,280 2,130 1,400 1,970 5,507 60% 14,080 15,400 15,300 12,500 10,100 5,964 4,608 3,866 2,470 1,510 2,300 6,796 65% 15,100 16,300 16,300 14,200 11,400 6,980 5,080 4,390 3,020 1,670 2,770 8,290 70% 16,200 17,000 17,610 15,430 13,600 8,700 5,610 4,960 3,703 1,831 3,383 9,850 75% 17,700 18,200 19,000 16,900 15,800 10,600 6,183 5,420 4,270 2,060 4,293 12,000 80% 19,840 19,760 20,700 18,500 17,400 12,800 6,860 5,934 5,042 2,660 5,700 13,900 85% 23,000 21,800 22,900 21,100 20,400 16,700 8,111 6,510 5,900 3,576 7,600 16,855 90% 27,370 25,180 26,170 25,700 26,300 20,000 9,751 7,050 7,321 5,657 9,950 19,470 95% 34,885 32,080 32,700 32,805 38,300 27,410 14,570 8,080 9,061 9,865 16,105 24,300 96% 36,700 34,100 34,888 34,124 40,600 29,500 16,388 8,420 9,882 11,000 18,000 26,000 97% 39,182 37,936 37,600 36,843 44,400 31,629 18,000 9,775 11,629 12,500 21,800 27,700 98% 42,800 45,168 40,300 40,224 49,058 36,348 21,600 12,670 13,862 14,194 26,400 31,582 99% 48,879 54,952 47,688 47,500 61,882 41,962 31,195 24,079 17,010 24,297 32,481 39,000 max 82,000 90,600 82,600 83,500 120,000 78,100 108,000 67,000 50,500 56,600 53,700 88,100 11
Table 2-7 Monthly Percentiles at Neches River near Neches. Statistic: Percentile flow magnitudes (cfs), by month. Site: Neches River near Neches, TX (USGS guage no. 08032000) Start January, 1940 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 51 96 63 29 27 15 4 1 1 3 3 25 1% 65 125 86 62 36 22 7 2 2 4 9 36 2% 88 140 108 74 55 24 10 4 3 6 20 55 3% 93 151 118 82 71 27 14 6 4 7 24 66 4% 98 164 127 95 80 38 17 8 5 12 27 73 5% 100 169 138 102 88 46 19 9 6 13 30 77 10% 135 224 203 159 139 77 30 19 20 22 59 101 15% 167 285 276 235 184 89 41 24 27 31 77 119 20% 195 331 380 311 226 109 56 29 34 44 88 137 25% 224 396 473 390 276 133 67 36 46 55 99 159 30% 275 450 560 456 340 166 75 43 54 67 115 186 35% 312 538 660 522 444 201 82 50 61 76 128 207 40% 360 611 766 590 520 236 95 58 71 82 142 243 45% 446 712 876 665 596 298 109 65 79 89 165 287 50% 548 800 985 750 691 362 122 73 86 98 180 350 55% 644 901 1,090 848 805 452 138 80 92 111 201 415 60% 756 990 1,180 962 927 551 159 90 98 129 221 529 65% 885 1,090 1,280 1,050 1,070 659 181 98 108 147 250 638 70% 1,010 1,180 1,470 1,190 1,226 795 206 105 122 170 296 773 75% 1,205 1,350 1,690 1,350 1,460 925 245 117 140 200 380 916 80% 1,474 1,570 1,970 1,540 1,730 1,070 320 133 172 256 507 1,104 85% 1,820 1,870 2,250 1,780 2,200 1,320 440 156 206 336 746 1,340 90% 2,360 2,261 2,800 2,261 3,000 1,710 632 194 312 482 1,111 1,786 95% 3,291 3,197 3,541 3,517 4,411 2,621 1,001 295 667 843 1,820 2,550 96% 3,669 3,591 3,950 4,322 4,945 2,967 1,075 357 782 958 2,145 2,760 97% 4,133 4,352 4,397 4,937 5,680 3,420 1,219 496 1,079 1,159 2,469 3,140 98% 4,745 5,231 5,010 6,060 7,519 4,242 1,707 634 1,440 1,440 2,900 4,492 99% 5,588 6,151 6,348 9,213 12,362 6,025 2,765 975 1,959 1,989 4,190 6,425 max 15,500 15,100 12,400 44,100 26,200 13,500 18,700 4,670 3,790 5,100 10,700 15,800 12
Table 2-8 Monthly Percentiles at Neches River near Rockland. Statistic: Percentile flow magnitudes (cfs), by month. Site: Neches Rv near Rockland, TX (USGS guage no. 08033500) Start January, 1913 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 67 230 188 151 91 20 9 4 2 2 5 33 1% 104 270 345 230 166 71 27 9 6 4 21 99 2% 150 301 375 268 206 102 35 18 9 6 34 118 3% 215 338 393 325 256 119 42 21 12 8 40 141 4% 235 363 405 378 294 133 51 24 16 11 42 160 5% 256 408 435 425 328 151 59 27 20 20 50 176 10% 399 576 622 645 447 215 91 46 44 38 78 248 15% 540 874 899 912 574 281 119 61 56 55 110 298 20% 650 1,150 1,240 1,110 694 342 145 75 67 72 141 357 25% 833 1,450 1,550 1,300 879 399 170 88 80 88 168 415 30% 1,070 1,766 1,910 1,440 1,060 483 198 104 95 101 201 512 35% 1,400 2,050 2,183 1,687 1,300 615 229 119 110 113 235 633 40% 1,690 2,440 2,460 1,960 1,520 802 272 136 128 128 276 754 45% 2,058 2,730 2,790 2,210 1,880 958 318 154 145 151 349 950 50% 2,400 3,200 3,080 2,500 2,320 1,170 375 182 169 175 431 1,140 55% 2,780 3,560 3,440 2,835 2,830 1,440 434 206 192 208 519 1,400 60% 3,190 3,980 3,800 3,200 3,260 1,720 510 231 217 249 645 1,800 65% 3,688 4,360 4,290 3,600 3,780 2,024 633 261 256 284 784 2,298 70% 4,220 4,857 4,960 4,100 4,525 2,423 785 301 303 358 926 2,885 75% 4,960 5,440 5,750 4,773 5,400 2,870 995 345 370 480 1,100 3,520 80% 5,960 6,170 6,660 5,850 6,510 3,440 1,280 413 505 645 1,410 4,180 85% 7,185 7,257 7,750 7,203 7,908 4,220 1,750 567 692 881 2,212 5,115 90% 9,000 8,705 9,345 9,090 10,200 5,942 2,560 827 954 1,335 3,481 6,330 95% 12,400 11,345 11,300 11,800 14,000 9,140 3,868 1,330 1,681 2,860 6,776 9,003 96% 13,900 12,256 12,000 12,600 15,200 10,100 4,400 1,500 1,860 3,560 8,660 9,710 97% 15,100 13,267 13,300 13,663 17,850 11,500 5,738 1,910 2,086 4,268 10,963 11,000 98% 16,700 14,778 15,050 15,900 23,100 13,526 9,480 2,765 2,441 5,800 12,542 12,600 99% 19,350 18,278 18,600 21,300 29,900 19,384 13,500 4,650 3,166 7,725 15,421 14,325 max 35,800 33,600 30,400 45,200 49,700 34,200 41,600 13,300 10,300 41,500 26,900 24,800 13
Table 2-9 Monthly Percentiles at Angelina River near Alto. Statistic: Percentile flow magnitudes (cfs), by month. Site: Angelina River near Alto, TX (USGS guage no. 08036500) Start January, 1960 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 55 101 90 70 27 12 0 0 0 4 8 25 1% 93 129 153 111 54 20 5 4 5 5 18 48 2% 105 146 159 134 65 25 7 6 7 8 20 63 3% 114 154 169 145 72 30 9 10 8 14 22 77 4% 127 170 186 160 77 36 13 11 9 16 24 85 5% 134 184 216 175 84 40 16 13 10 18 27 90 10% 166 270 307 216 121 60 31 21 18 27 50 110 15% 226 368 379 271 156 70 44 30 27 38 63 130 20% 287 456 480 342 189 85 52 36 39 44 75 150 25% 368 541 600 412 231 111 59 45 45 51 94 182 30% 457 654 684 477 276 146 67 49 53 57 116 252 35% 561 750 774 562 328 176 77 55 59 62 143 308 40% 644 864 867 632 409 206 87 60 67 71 179 389 45% 752 971 982 688 498 250 103 65 73 81 219 489 50% 878 1,080 1,110 776 581 302 120 71 81 91 251 570 55% 980 1,230 1,239 888 702 374 140 80 91 104 297 684 60% 1,130 1,400 1,428 1,040 859 440 161 88 103 121 345 851 65% 1,337 1,640 1,597 1,250 1,017 520 194 96 115 146 420 1,060 70% 1,570 1,858 1,870 1,440 1,220 656 226 108 134 179 488 1,300 75% 1,800 2,090 2,180 1,600 1,445 854 279 128 160 228 609 1,500 80% 2,060 2,442 2,560 1,892 1,814 1,172 360 156 207 314 765 1,794 85% 2,513 2,914 2,993 2,333 2,336 1,467 519 196 274 444 1,020 2,180 90% 3,252 3,650 3,690 2,903 3,140 1,962 824 256 443 699 1,291 2,858 95% 4,663 5,312 5,230 4,566 4,346 3,336 1,371 563 883 1,361 1,841 3,930 96% 5,223 5,730 5,700 5,327 4,950 3,752 1,598 779 1,002 1,563 2,030 4,399 97% 6,201 6,413 6,276 6,137 5,750 4,229 1,835 1,024 1,219 1,885 2,508 5,244 98% 7,282 7,090 7,100 7,213 6,925 5,262 2,483 1,250 1,489 2,431 3,103 6,786 99% 8,987 8,410 8,575 8,935 9,300 6,845 4,530 1,638 1,879 3,325 4,159 8,866 max 23,100 23,700 41,600 33,000 15,200 26,500 29,000 5,330 2,600 6,900 7,780 17,800 14
Table 2-10 Monthly Percentiles at Attoyac Bayou near Chireno. Statistic: Percentile flow magnitudes (cfs), by month. Site: Attoyac Bayou near Chireno, TX (USGS guage no. 08030800) Start January, 1940 End September, 1985 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 29 51 68 37 23 13 5 1 2 2 8 23 1% 32 65 80 49 31 17 6 3 5 4 13 28 2% 43 78 88 54 38 19 8 5 5 4 15 34 3% 46 87 98 59 41 22 9 6 6 6 17 41 4% 56 98 106 66 46 24 10 8 8 7 18 46 5% 69 110 109 73 49 25 11 9 9 9 20 49 10% 95 140 142 105 68 34 17 13 13 14 28 62 15% 115 173 170 125 84 43 23 16 17 20 38 77 20% 137 216 203 153 106 51 29 18 22 25 46 88 25% 166 264 242 182 124 61 34 22 28 28 53 106 30% 192 314 280 206 148 70 39 26 32 34 66 124 35% 234 360 316 227 173 77 46 30 36 37 80 136 40% 286 414 352 248 206 86 51 34 40 43 92 155 45% 344 473 386 276 242 98 56 39 45 50 112 184 50% 399 536 437 320 296 117 64 44 51 56 125 232 55% 452 595 488 367 347 136 76 51 58 66 141 287 60% 527 655 544 428 411 168 90 58 68 73 159 360 65% 647 724 617 500 494 206 102 65 78 83 184 446 70% 743 796 675 593 610 249 118 73 88 93 226 564 75% 885 906 790 700 744 318 138 83 106 111 303 661 80% 1,070 1,080 935 870 871 450 168 100 126 144 382 848 85% 1,360 1,304 1,159 1,120 1,200 626 205 124 173 196 566 1,076 90% 1,626 1,620 1,406 1,482 1,596 858 282 168 266 301 844 1,350 95% 2,190 2,183 1,803 2,170 2,440 1,430 538 298 638 629 1,340 1,937 96% 2,347 2,338 1,942 2,490 2,717 1,590 637 360 719 698 1,420 2,119 97% 2,610 2,687 2,342 2,905 3,362 1,770 724 473 927 828 1,680 2,502 98% 3,180 3,166 2,611 4,092 4,722 2,121 826 611 1,440 985 2,126 2,982 99% 4,084 4,006 3,806 6,641 7,228 3,246 929 919 2,867 1,428 3,215 4,591 max 9,900 9,310 14,600 16,700 15,600 14,100 1,650 2,200 15,500 11,800 26,800 8,940 15
Table 2-11 Monthly Percentiles at Neches River at Evadale. Statistic: Percentile flow magnitudes (cfs), by month. Site: Neches River at Evadale, TX (USGS guage no. 08041000) Start January, 1922 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 92 106 630 706 328 266 213 82 140 74 63 75 1% 244 287 930 1,001 717 536 315 174 172 155 115 160 2% 495 635 1,088 1,152 907 659 403 230 191 169 150 268 3% 585 962 1,180 1,270 1,010 780 451 268 206 184 178 363 4% 963 1,163 1,270 1,320 1,158 884 492 282 218 196 210 436 5% 1,050 1,299 1,380 1,490 1,240 965 547 290 230 217 230 480 10% 1,640 1,917 1,956 2,010 1,680 1,269 748 400 300 266 335 768 15% 1,930 2,350 2,540 2,644 2,160 1,490 927 507 384 341 425 1,010 20% 2,202 2,880 2,960 3,100 2,640 1,720 1,100 619 438 397 502 1,240 25% 2,590 3,720 3,700 3,660 3,150 2,160 1,290 700 508 465 633 1,460 30% 2,930 4,800 4,644 4,210 3,540 2,487 1,460 835 587 519 870 1,720 35% 3,410 5,549 5,826 5,010 4,006 2,940 1,660 969 736 597 1,100 1,920 40% 4,210 6,460 6,858 5,700 4,610 3,290 1,944 1,150 925 770 1,346 2,300 45% 5,190 7,497 7,910 6,580 5,400 3,580 2,240 1,420 1,090 1,040 1,601 2,590 50% 6,220 8,400 8,840 7,595 6,080 3,880 2,640 1,710 1,405 1,420 1,935 2,910 55% 7,130 9,480 10,200 8,480 7,050 4,400 3,050 1,990 1,750 1,840 2,340 3,390 60% 8,120 10,600 11,800 9,600 8,196 5,120 3,320 2,230 2,150 2,250 2,580 4,090 65% 9,270 11,700 13,800 11,100 9,730 6,069 3,490 2,760 2,650 2,470 2,770 5,114 70% 10,620 13,100 15,620 12,800 11,400 7,033 3,720 3,080 2,843 2,680 3,013 6,200 75% 12,600 14,500 17,000 14,600 13,700 8,188 4,090 3,260 3,020 2,840 3,300 7,420 80% 15,300 16,500 18,300 16,620 15,880 10,400 4,798 3,460 3,190 3,080 3,762 9,270 85% 18,100 18,700 19,600 19,000 18,300 14,500 6,610 3,660 3,420 3,330 4,897 11,300 90% 20,940 20,500 21,200 20,900 20,300 17,500 8,328 4,472 4,291 4,120 7,721 14,000 95% 25,000 22,600 24,400 24,110 26,040 21,100 13,400 6,650 5,911 6,764 13,200 20,020 96% 26,548 23,500 25,500 26,200 30,580 23,100 15,300 7,412 6,473 8,018 15,964 21,000 97% 28,400 24,800 26,824 28,600 37,824 26,373 16,900 9,030 7,069 8,972 20,000 23,700 98% 30,600 26,072 28,124 34,500 46,700 30,328 18,108 11,000 7,891 11,108 22,446 28,500 99% 34,120 33,800 31,904 45,410 59,600 39,564 19,304 13,844 10,083 18,512 27,000 34,816 max 44,600 73,400 73,400 71,500 92,100 83,800 47,400 18,500 18,400 41,000 47,100 59,600 16
Table 2-12 Monthly Percentiles at Village Creek near Kountze. Statistic: Percentile flow magnitudes (cfs), by month. Site: Village Creek near Kountze, TX (USGS guage no. 08041500) Start January, 1940 End December, 2008 month percentile level Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec min 83 118 137 70 55 44 20 22 18 16 24 37 1% 92 132 157 115 74 55 32 28 25 22 36 56 2% 120 145 175 134 82 58 36 31 30 26 44 85 3% 138 156 192 142 88 66 43 34 35 35 52 99 4% 147 177 204 152 94 72 50 38 40 37 55 109 5% 155 206 211 160 100 78 52 44 42 39 58 114 10% 207 295 255 207 129 92 69 53 54 50 80 147 15% 251 365 300 244 154 102 80 61 64 61 97 175 20% 310 449 362 273 177 116 94 70 71 74 115 209 25% 387 516 418 306 201 132 108 80 81 86 132 253 30% 476 586 483 338 237 152 122 89 91 92 150 306 35% 564 668 552 377 273 172 134 98 100 101 172 371 40% 648 766 631 418 315 200 148 108 110 112 197 430 45% 738 848 701 467 359 237 163 119 119 123 224 491 50% 831 935 778 519 415 286 183 132 129 137 255 586 55% 959 1,050 854 590 470 327 212 144 141 160 291 676 60% 1,100 1,190 948 666 546 386 248 160 154 174 345 794 65% 1,317 1,360 1,070 772 655 464 289 176 170 196 406 939 70% 1,500 1,573 1,240 914 794 570 337 194 199 229 482 1,100 75% 1,830 1,800 1,450 1,118 1,080 730 412 219 237 268 582 1,335 80% 2,230 2,130 1,760 1,412 1,400 944 520 255 312 332 789 1,664 85% 2,720 2,570 2,150 1,810 1,810 1,270 704 320 394 422 1,157 2,030 90% 3,550 3,310 2,710 2,300 2,672 1,881 1,052 450 588 626 1,790 2,680 95% 4,641 4,900 3,623 3,622 4,094 3,230 1,950 760 1,214 1,541 2,780 3,930 96% 5,180 5,331 3,905 4,045 4,580 3,672 2,200 961 1,502 2,035 3,330 4,490 97% 5,967 5,831 4,293 4,750 5,293 4,457 2,593 1,286 1,929 2,884 4,076 5,093 98% 7,422 6,861 4,845 5,894 6,282 5,468 3,344 2,009 2,481 4,310 5,516 5,841 99% 9,187 9,101 5,673 9,062 9,492 8,900 4,372 3,210 4,093 8,564 10,593 7,494 max 21,100 21,600 12,600 44,600 42,800 56,200 34,400 8,850 18,400 52,900 62,200 31,900 17
Table 3-1 Seasonal Percentiles at Big Sandy Creek near Big Sandy. Percentile flow magnitudes (cfs), by season. Site: Big Sandy Creek near Big Sandy, TX (USGS guage no. 08019500) Start January, 1940 End December, 2007 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 20 5 0 1 1% 31 11 4 7 2% 35 14 5 9 3% 39 17 6 12 4% 43 19 7 13 5% 47 21 7 14 10% 61 30 10 18 15% 74 39 12 21 20% 84 46 14 26 25% 98 57 16 31 30% 113 66 17 35 35% 128 77 19 41 40% 142 89 21 46 45% 157 104 24 52 50% 173 118 26 59 55% 190 135 29 68 60% 211 155 31 79 65% 238 179 35 95 70% 270 210 39 116 75% 314 250 45 141 80% 375 296 55 172 85% 464 388 73 216 90% 625 550 102 302 95% 920 900 184 556 96% 1,010 1,020 215 635 97% 1,150 1,210 254 747 98% 1,330 1,558 355 929 99% 1,710 2,465 614 1,369 max 17,900 11,400 4,000 5,530 18
Table 3-2 Seasonal Percentiles at Sabine River near Gladewater. Percentile flow magnitudes (cfs), by season. Site: Sabine River near Gladewater, TX (USGS guage no. 08020000) Start January, 1933 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 45 22 6 7 1% 115 39 10 14 2% 151 59 11 22 3% 176 70 13 25 4% 194 82 14 31 5% 217 95 16 36 10% 306 150 26 54 15% 379 210 32 78 20% 460 282 40 96 25% 552 362 48 116 30% 682 456 57 142 35% 808 573 71 173 40% 968 712 83 211 45% 1,180 890 96 254 50% 1,420 1,150 111 303 55% 1,730 1,490 125 372 60% 2,138 1,910 145 464 65% 2,627 2,420 171 604 70% 3,200 3,020 212 825 75% 3,840 3,820 273 1,160 80% 4,700 4,670 376 1,628 85% 5,540 5,830 535 2,373 90% 6,660 7,140 900 3,439 95% 8,803 10,500 1,940 5,760 96% 9,764 12,400 2,324 6,400 97% 11,200 14,900 2,910 7,233 98% 13,100 18,770 3,694 8,873 99% 16,642 28,055 5,663 12,918 max 40,600 133,000 19,200 44,500 19
Table 3-3 Seasonal Percentiles at Sabine River near Beckville. Percentile flow magnitudes (cfs), by season. Site: Sabine Rv near Beckville, TX (USGS guage no. 08022040) Start January, 1939 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 66 27 2 7 1% 170 68 11 18 2% 233 98 15 29 3% 277 121 18 40 4% 305 143 22 47 5% 335 166 24 54 10% 474 281 40 81 15% 610 400 53 110 20% 767 522 71 138 25% 940 677 88 170 30% 1,160 841 108 214 35% 1,410 1,052 128 266 40% 1,700 1,290 147 336 45% 2,017 1,600 169 404 50% 2,420 2,010 193 498 55% 2,980 2,450 225 615 60% 3,582 2,980 266 789 65% 4,230 3,680 319 1,060 70% 4,940 4,480 387 1,350 75% 5,690 5,420 487 1,863 80% 6,636 6,400 668 2,620 85% 7,770 7,800 966 3,542 90% 9,203 9,861 1,550 5,011 95% 11,300 12,900 2,840 7,530 96% 11,800 14,224 3,434 8,319 97% 12,449 16,500 4,303 9,500 98% 13,666 19,800 5,584 11,000 99% 18,700 27,600 7,679 13,200 max 39,000 120,000 17,200 36,400 20
Table 3-4 Seasonal Percentiles at Sabine River near Bon Wier. Percentile flow magnitudes (cfs), by season. Site: Sabine River near Bon Wier, TX (USGS guage no. 08028500) Start January, 1924 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 479 251 160 134 1% 675 506 205 199 2% 772 629 235 234 3% 860 700 260 259 4% 941 770 288 282 5% 1,020 839 315 311 10% 1,450 1,080 423 418 15% 1,950 1,400 540 516 20% 2,550 1,780 670 610 25% 3,500 2,220 785 702 30% 4,550 2,740 913 820 35% 5,930 3,190 1,050 926 40% 7,220 3,706 1,220 1,040 45% 8,490 4,350 1,450 1,160 50% 9,800 5,170 1,795 1,320 55% 11,200 6,150 2,200 1,520 60% 12,800 7,550 2,664 1,790 65% 14,900 8,850 3,290 2,260 70% 15,900 10,600 3,950 2,963 75% 16,600 13,100 4,603 4,043 80% 17,800 15,600 5,322 6,020 85% 20,000 17,600 6,000 7,970 90% 23,000 22,000 6,960 10,900 95% 28,100 29,100 8,540 16,505 96% 29,600 31,528 9,985 18,000 97% 31,000 34,800 12,000 20,000 98% 34,200 38,800 15,000 22,462 99% 42,558 45,796 20,681 27,200 max 90,500 111,000 98,000 81,400 21
Table 3-5 Seasonal Percentiles at Big Cow Creek near Newton. Percentile flow magnitudes (cfs), by season. Site: Big Cow Creek near Newton, TX (USGS guage no. 08029500) Start January, 1953 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 28 12 10 14 1% 34 19 14 18 2% 38 22 15 19 3% 41 24 17 21 4% 43 26 18 22 5% 44 27 19 24 10% 52 32 23 28 15% 58 36 25 32 20% 64 41 27 36 25% 70 45 29 40 30% 78 49 31 43 35% 85 53 34 46 40% 92 58 36 50 45% 100 63 39 54 50% 109 68 42 60 55% 119 74 45 66 60% 128 81 49 73 65% 141 90 52 82 70% 155 100 57 93 75% 176 112 63 107 80% 206 130 72 129 85% 260 164 85 162 90% 370 238 104 226 95% 669 480 145 408 96% 759 579 165 510 97% 868 703 202 658 98% 1,080 912 295 892 99% 1,459 1,300 544 1,260 max 9,720 9,520 4,710 23,200 22
Table 3-6 Seasonal Percentiles at Sabine River near Ruliff. Percentile flow magnitudes (cfs), by season. Site: Sabine River near Ruliff, TX (USGS guage no. 08030500) Start January, 1925 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 949 431 270 270 1% 1,198 845 342 307 2% 1,300 1,010 393 353 3% 1,400 1,143 423 400 4% 1,520 1,220 450 440 5% 1,650 1,310 475 470 10% 2,330 1,640 678 662 15% 2,940 2,080 852 855 20% 3,810 2,566 1,040 995 25% 5,000 3,050 1,240 1,130 30% 6,420 3,509 1,430 1,250 35% 8,000 4,130 1,640 1,390 40% 9,420 4,800 1,940 1,540 45% 10,800 5,674 2,280 1,700 50% 12,200 6,700 2,690 1,910 55% 13,800 8,120 3,199 2,200 60% 15,000 9,520 3,770 2,720 65% 15,900 11,000 4,290 3,330 70% 17,000 12,900 4,839 4,299 75% 18,400 15,100 5,410 5,603 80% 20,200 17,000 6,026 7,456 85% 22,600 19,700 6,770 9,919 90% 26,400 23,600 7,730 13,300 95% 33,100 32,900 10,700 19,465 96% 35,560 35,500 12,400 21,700 97% 38,500 38,500 14,200 24,119 98% 42,480 43,000 17,000 26,800 99% 51,100 51,656 26,292 33,473 max 90,600 120,000 108,000 88,100 23
Table 3-7 Seasonal Percentiles at Neches River near Neches. Percentile flow magnitudes (cfs), by season. Site: Neches River near Neches, TX (USGS guage no. 08032000) Start January, 1940 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 51 15 1 3 1% 86 27 2 6 2% 98 41 5 13 3% 106 57 6 17 4% 119 68 9 21 5% 129 75 11 24 10% 171 102 22 44 15% 215 139 28 68 20% 276 186 37 80 25% 330 233 47 90 30% 402 294 56 104 35% 486 369 64 120 40% 574 452 73 136 45% 671 528 80 156 50% 775 610 89 179 55% 890 707 98 202 60% 994 820 108 234 65% 1,100 940 121 279 70% 1,220 1,070 138 353 75% 1,440 1,230 162 464 80% 1,680 1,460 192 620 85% 2,010 1,760 240 863 90% 2,500 2,320 372 1,173 95% 3,390 3,562 708 1,860 96% 3,809 4,109 840 2,100 97% 4,302 4,867 1,026 2,408 98% 5,029 5,946 1,250 2,920 99% 6,020 9,114 2,000 4,502 max 15,500 44,100 18,700 15,800 24
Table 3-8 Seasonal Percentiles at Neches River near Rockland. Percentile flow magnitudes (cfs), by season. Site: Neches Rv near Rockland, TX (USGS guage no. 08033500) Start January, 1913 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 67 20 2 2 1% 208 116 9 8 2% 256 153 16 20 3% 307 182 21 29 4% 345 208 27 37 5% 375 231 33 40 10% 512 350 53 71 15% 702 461 68 104 20% 960 608 87 128 25% 1,260 785 104 160 30% 1,560 988 122 197 35% 1,880 1,190 141 244 40% 2,210 1,390 164 286 45% 2,530 1,650 190 354 50% 2,900 1,960 215 435 55% 3,260 2,310 253 547 60% 3,680 2,710 292 684 65% 4,140 3,140 345 855 70% 4,690 3,620 406 1,070 75% 5,390 4,280 525 1,400 80% 6,260 5,340 692 2,020 85% 7,416 6,638 948 3,000 90% 9,070 8,580 1,370 4,420 95% 11,600 11,925 2,444 6,894 96% 12,600 13,000 2,858 7,815 97% 14,000 14,300 3,440 9,290 98% 15,800 17,600 4,280 11,438 99% 18,800 24,760 7,905 14,100 max 35,800 49,700 41,600 41,500 25
Table 3-9 Seasonal Percentiles at Angelina River near Alto Percentile flow magnitudes (cfs), by season. Site: Angelina River near Alto, TX (USGS guage no. 08036500) Start January, 1960 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 55 12 0 4 1% 107 30 5 12 2% 130 42 7 18 3% 140 54 9 21 4% 152 61 10 24 5% 160 66 12 26 10% 239 96 23 46 15% 314 142 33 57 20% 401 180 42 69 25% 495 217 49 87 30% 600 265 56 104 35% 692 324 62 123 40% 794 396 68 145 45% 900 472 76 179 50% 1,010 557 86 229 55% 1,150 653 96 282 60% 1,330 765 109 353 65% 1,530 923 128 443 70% 1,760 1,120 150 562 75% 2,020 1,370 183 723 80% 2,350 1,630 229 981 85% 2,840 2,050 313 1,310 90% 3,570 2,742 494 1,750 95% 5,107 4,150 1,027 2,760 96% 5,670 4,634 1,200 3,157 97% 6,300 5,450 1,370 3,486 98% 7,110 6,578 1,669 4,057 99% 8,596 8,820 2,387 6,287 max 41,600 33,000 29,000 17,800 26
Table 3-10 Seasonal Percentiles at Attoyac Bayou near Chireno. Percentile flow magnitudes (cfs), by season. Site: Attoyac Bayou near Chireno, TX (USGS guage no. 08030800) Start January, 1940 End September, 1985 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 29 13 1 2 1% 46 22 5 6 2% 66 27 6 10 3% 78 31 8 12 4% 86 35 8 14 5% 90 39 9 16 10% 122 54 14 25 15% 148 69 17 34 20% 178 84 23 42 25% 213 103 28 50 30% 259 122 32 60 35% 304 146 36 72 40% 352 176 42 83 45% 394 206 47 96 50% 446 239 53 113 55% 511 274 60 132 60% 585 331 69 154 65% 660 399 79 186 70% 745 486 91 238 75% 864 610 108 328 80% 1,038 753 132 446 85% 1,260 965 170 622 90% 1,550 1,350 238 922 95% 2,070 2,050 504 1,382 96% 2,250 2,310 608 1,549 97% 2,500 2,672 702 1,820 98% 3,160 3,643 873 2,190 99% 4,032 5,741 1,346 3,130 max 14,600 16,700 15,500 26,800 27
Table 3-11 Seasonal Percentiles at Neches River at Evadale. Percentile flow magnitudes (cfs), by season. Site: Neches River at Evadale, TX (USGS guage no. 08041000) Start January, 1922 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 92 266 82 63 1% 448 691 189 135 2% 660 877 222 170 3% 982 999 252 196 4% 1,140 1,100 270 224 5% 1,240 1,180 290 243 10% 1,820 1,540 414 352 15% 2,210 1,950 513 451 20% 2,640 2,400 641 535 25% 3,080 2,940 780 740 30% 3,890 3,320 945 962 35% 4,849 3,750 1,120 1,240 40% 5,814 4,244 1,340 1,490 45% 6,840 4,920 1,614 1,820 50% 7,805 5,660 1,910 2,200 55% 8,770 6,580 2,220 2,460 60% 10,000 7,580 2,690 2,700 65% 11,400 8,714 2,980 2,920 70% 13,200 10,400 3,180 3,200 75% 15,200 12,700 3,400 3,680 80% 17,100 15,000 3,630 4,748 85% 19,000 17,560 4,210 6,566 90% 20,800 19,800 5,600 9,477 95% 24,000 23,700 8,390 14,400 96% 25,100 26,200 9,448 16,776 97% 26,800 30,000 11,300 20,000 98% 29,100 37,568 14,100 22,300 99% 33,345 48,500 17,300 28,597 max 73,400 92,100 47,400 59,600 28
Table 3-12 Seasonal Percentiles at Village Creek near Kountze. Percentile flow magnitudes (cfs), by season. Site: Village Creek near Kountze, TX (USGS guage no. 08041500) Start January, 1940 End December, 2008 season percentile Winter Spring Summer Fall level Jan-Mar Apr-Jun Jul-Sep Oct-Dec min 83 44 18 16 1% 129 64 28 33 2% 143 76 32 38 3% 156 83 36 44 4% 170 88 42 48 5% 187 93 45 51 10% 244 120 57 73 15% 300 145 67 91 20% 367 172 77 108 25% 438 203 88 124 30% 515 239 99 145 35% 590 276 109 167 40% 672 315 120 190 45% 758 358 132 222 50% 841 406 144 258 55% 944 467 159 309 60% 1,062 543 177 372 65% 1,240 639 200 449 70% 1,440 771 233 550 75% 1,700 958 282 690 80% 2,050 1,240 351 937 85% 2,490 1,640 453 1,300 90% 3,150 2,252 685 1,893 95% 4,350 3,720 1,390 3,087 96% 4,680 4,179 1,700 3,600 97% 5,332 4,790 2,120 4,288 98% 6,275 5,949 2,681 5,511 99% 8,179 9,107 4,001 8,432 max 21,600 56,200 34,400 62,200 29
Table 4-1 Estuary Inflow Percentiles for Sabine Lake. Inflow Statistic: Percentile flow magnitudes (1000 ACFT per month), by years, seasons and months. Total Inflow to Sabine Lake. Start January, 1941 End December, 2005 annual season month Winter Spring Summer Fall Dec-Feb Mar-May Jun-Aug Sep-Nov Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 0% 3,183 573 953 532 94 121 261 237 152 180 150 58 36 26 32 50 176 1% 3,800 721 1,012 643 120 193 275 260 268 243 151 91 38 29 41 54 192 2% 4,303 819 1,054 741 136 253 290 287 345 289 160 111 40 33 47 58 203 3% 4,659 852 1,073 821 137 298 307 322 372 314 180 115 40 39 48 60 207 4% 4,859 886 1,143 866 172 308 315 332 382 358 195 125 44 42 50 72 217 5% 4,990 916 1,239 920 202 314 322 353 393 395 206 134 49 49 51 82 225 10% 5,553 1,112 1,794 1,150 293 368 378 492 518 437 302 178 77 137 73 98 297 15% 7,201 1,402 2,209 1,459 700 445 518 612 584 454 402 224 135 168 107 172 363 20% 7,778 1,621 2,452 1,574 816 569 664 662 663 487 505 272 210 236 126 224 380 25% 8,562 1,803 2,649 1,819 1,037 675 939 910 837 665 550 354 312 291 151 282 415 30% 9,801 1,970 3,135 2,106 1,184 799 1,107 960 936 800 591 493 354 363 198 311 459 35% 10,960 2,159 3,949 2,302 1,382 929 1,251 1,099 1,020 930 609 558 431 443 270 348 505 40% 11,934 2,381 4,177 2,609 1,492 1,163 1,310 1,329 1,133 1,070 720 600 460 473 326 370 573 45% 13,480 2,588 4,509 2,876 1,571 1,226 1,454 1,738 1,174 1,126 779 625 486 512 352 394 675 50% 14,743 2,967 5,288 3,226 1,626 1,312 1,570 1,930 1,310 1,212 902 681 517 536 398 441 928 55% 15,977 3,418 5,477 3,496 1,726 1,396 1,705 1,978 1,495 1,461 1,053 747 592 561 406 485 1,006 60% 16,287 3,780 5,782 3,717 1,812 1,619 1,864 2,209 1,656 1,519 1,149 854 629 596 449 571 1,201 65% 17,399 4,073 6,046 3,920 1,950 1,976 2,028 2,380 1,757 1,876 1,432 976 660 641 506 647 1,428 70% 18,063 4,549 6,433 5,104 2,060 2,161 2,179 2,493 2,072 2,050 1,738 1,164 692 684 595 729 1,684 75% 19,020 5,122 6,664 5,571 2,403 2,260 2,496 2,528 2,198 2,453 1,949 1,294 760 830 727 805 1,733 80% 20,503 5,463 7,439 5,963 2,613 2,707 2,563 2,664 2,375 2,573 2,158 1,337 851 978 913 891 1,902 85% 21,230 5,858 8,125 6,957 2,922 3,181 2,722 2,853 2,616 2,852 2,477 1,480 930 1,196 1,108 1,176 2,251 90% 23,130 6,397 8,812 7,732 3,610 3,646 2,970 3,013 2,920 2,999 2,663 1,742 1,067 1,471 1,305 1,632 2,428 95% 25,606 7,856 9,478 8,442 4,195 4,047 3,132 3,382 3,613 3,982 3,396 1,891 1,255 1,986 2,074 2,499 2,757 96% 25,673 7,909 9,754 9,217 4,579 4,146 3,172 3,646 3,796 4,288 3,560 1,999 1,306 2,050 2,199 2,658 2,795 97% 25,787 8,055 10,057 10,169 5,056 4,264 3,244 3,982 3,988 4,769 3,777 2,141 1,360 2,060 2,279 2,730 2,841 98% 26,374 8,749 10,341 10,431 5,258 4,406 3,725 3,993 4,249 6,511 3,950 2,254 1,380 2,088 2,342 2,753 2,948 99% 27,490 9,158 10,923 11,363 5,496 5,167 4,146 4,381 5,073 7,568 4,273 3,543 1,413 2,422 2,865 2,841 3,170 100% 29,017 9,344 11,737 12,815 5,763 6,409 4,520 5,061 6,334 8,091 4,713 5,747 1,455 2,995 3,746 2,980 3,480 percentile level 30