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San Francisco Public Utilities Commission
Correspondence Log
June 9, 2022 through June 22, 2022
Date Received From Subject
June 9, 2022 Brian Browne Probabilistic analysis of drought planning "Regulatory Failure or
Success?"
June 12, 2022 Eileen Boken One way to help heal Central Valley while correcting political favoritism
June 13, 2022 Spreck Rosekrans Commendation upon the retirement of Michael Carlin
Peter Drekmeier Drought Frequency Methodology
June 14, 2022 Dave Warner Public Comments – June 14, 2022 June 21, 2022 David Romano The fight for a starry night June 22, 2022 Nicole Sandkulla Thank you and Congratulations on Your Retirement
From: Brian Browne
To: Carlin, Michael (PUC); Ritchie, Steve; Hood, Donna
Cc: Peter Drekmeier; Elsbernd, Sean (MYR); bodisco
Subject: probabilistic analysis of drought planning -"Regulatory Failure or Success?" Date: Thursday, June 9, 2022 4:17:53 PM
CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe.
Dear Ms Hood and Messrs Ritchie and Carlin,
Your designer drought period has caught my interest.
How did you select the historic drought periods to quantify such? Here is the database I have for Tuolumne River flows. I believe it was sent to me by Mr. Carlin. Are these data correct? Do you have a more current and up to data set? Please forward.
I would like to assess the probabilities of your design drought based mainly on Tuolumne River Flows. Before starting it is of paramount importance I have the correct data set. Your help will be greatly appreciated.
I will share my results.
Now is a time that we should all be putting our oars in the water together for the common good. I am working on a tome "Regulatory Failure or Success?" based on my experiences as the economist on the Mayor's infrastructure Taskforce, as a member of the Revenue Bond Oversight Committee (I coauthored the enabling legislation [2002 Proposition P] - the outcome [implementation] of which did not reflect what was presented to and overwhelmingly approved by the voters) and other academic and industrial research pursuits with an emphasis on regulatory efficiency and resultant economic impacts. I believe you are aware of my 4th Estate outreach activities.
My work is self financed. Please get back to me ASAP.
Cheers,
Brian Browne
PS It is the work of Peter Drekmeier and the Tuolumne River Trust that catalyzed this particular thrust Acre Feet per Period
Year Jan Feb Mar Apr May June July Aug Sept Oct Nov
Dec CY
TOTAL
WY
Total
1901 223,000 436,000 245,000 257,000 532,000 590,000 252,000 51,900 10,700 13,700 35,900 86,400 2,733,6002,733,600
1902 22,500 84,000 139,000 292,000 398,000 401,000 84,200 27,000 6,140 7,840 41,000 50,9001,553,580 1,589,840 1903 123,000 93,700 195,000 341,000 479,000 439,000 83,400 16,500 7,010 5,400 59,300 26,6001,868,910 1,877,350 1904 26,000 217,000 334,000 350,000 656,000 517,000 164,000 46,500 37,600 197,000 45,400 28,5002,619,000 2,439,400 1905 45,200 103,000 200,000 227,000 345,000 337,000 81,300 14,900 6,420 2,410 3,530 8,2801,374,040 1,630,720 1906 180,000 120,000 453,000 400,000 699,000 852,000 731,000 133,000 27,800 12,400 16,100 92,4003,716,700 3,610,020 1907 149,000 238,000 697,000 579,000 642,000 662,000 498,000 133,000 30,600 18,300 18,000 38,0003,702,900 3,749,500 1908 58,700 47,000 112,000 207,000 251,000 182,000 62,600 23,900 5,060 13,800 12,800 21,100 996,960 1,023,560 1909 405,000 276,000 180,000 340,000 520,000 646,000 212,000 31,800 10,900 28,400 154,000 237,0003,041,100 2,669,400 1910 197,000 108,000 241,000 419,000 465,000 202,000 51,400 12,100 16,800 16,600 20,300 39,8001,789,000 2,131,700 1911 373,000 221,000 450,000 438,000 516,000 817,000 451,000 63,800 15,600 9,350 8,450 13,9003,377,100 3,422,100 1912 27,700 27,700 60,600 101,000 333,000 384,000 65,800 12,400 7,080 3,530 26,500 12,6001,061,910 1,050,980 1913 22,000 28,900 53,300 173,000 392,000 241,000 72,000 32,000 24,500 3,900 13,500 15,3001,071,400 1,081,330 1914 416,000 195,000 235,000 313,000 568,000 541,000 259,000 52,400 11,600 5,550 5,400 7,5002,609,450 2,623,700 1915 56,100 200,000 180,000 303,000 472,000 578,000 208,000 23,600 5,730 4,840 3,630 11,1002,046,000 2,044,880 1916 221,000 183,000 403,000 431,000 491,000 505,000 196,000 34,400 14,200 71,300 35,900 66,4002,652,200 2,498,170 1917 53,900 224,000 141,000 281,000 437,000 678,000 199,000 26,600 8,930 4,470 5,910 11,1002,070,910 2,223,030 1918 12,200 54,570 267,020 280,390 347,280 415,320 42,200 8,020 13,110 52,230 34,170 32,7101,559,220 1,461,590 1919 20,430 77,990 117,890 268,610 563,190 143,950 24,950 7,100 3,960 5,860 4,190 24,7301,262,850 1,347,180 1920 24,790 29,030 161,640 231,040 478,570 315,070 48,310 12,450 6,630 41,080 53,300 69,5501,471,460 1,342,310 1921 196,200 155,940 231,770 254,350 442,190 458,320 95,170 13,500 6,560 5,800 6,080 54,6001,920,480 2,017,930 1922 71,720 189,460 181,280 260,350 717,530 751,930 194,560 27,220 10,390 10,600 31,610 123,9302,570,580 2,470,920 1923 113,590 79,520 113,110 265,740 521,300 319,130 157,840 27,340 22,270 28,510 13,620 13,7601,675,730 1,785,980 1924 25,340 41,620 37,860 138,860 209,400 16,850 16,810 0 0 14,660 47,910 51,050 600,360 542,630 1925 44,260 227,090 165,640 350,330 538,440 352,380 111,860 22,650 5,850 15,120 16,210 32,7601,882,590 1,932,120 1926 18,950 100,580 127,440 382,300 303,780 89,230 18,910 3,250 1,380 5,480 74,080 60,0201,185,400 1,109,910 1927 63,200 223,130 159,720 351,500 454,090 476,180 146,290 24,590 13,120 15,340 87,010 44,1102,058,280 2,051,400 1928 51,260 82,210 343,420 263,770 447,770 152,650 27,620 7,300 2,560 0 5,790 18,1201,402,470 1,525,020 1929 19,060 40,450 99,400 148,100 378,120 224,690 40,740 4,570 0 1,860 1,240 23,030 981,260 979,040 1930 39,030 70,060 146,570 245,920 274,800 286,230 48,840 9,990 0 9,020 20,370 10,7201,161,550 1,147,570 1931 26,090 44,490 66,270 154,030 209,320 49,010 10,220 940 1,810 1,680 6,040 93,660 663,560 602,290 1932 79,370 240,200 171,590 245,050 524,150 532,660 175,840 31,970 12,040 5,720 3,200 10,8602,032,650 2,114,250 1933 26,900 31,480 82,590 170,940 250,820 426,150 75,100 16,070 4,540 0 7,960 40,8501,133,400 1,104,370 1934 64,910 89,980 150,250 186,390 149,040 95,090 12,070 6,110 4,570 11,180 47,620 51,950 869,160 807,220 1935 105,900 107,270 136,890 465,490 530,700 511,480 109,590 20,730 4,070 11,590 19,590 18,1602,041,460 2,102,870 1936 104,790 351,980 207,530 392,940 520,230 390,220 122,450 17,810 2,920 4,320 8,610 27,3202,151,1202,160,210 1937 31,430 273,900 209,510 295,600 633,900 399,410 91,360 16,850 4,800 9,150 18,760 312,5602,297,230 1,997,010 1938 101,940 322,740 424,840 422,380 720,160 711,600 305,190 55,470 19,540 40,250 43,490 36,7203,204,320 3,424,330 1939 42,590 59,920 144,110 281,900 216,040 74,340 17,340 7,480 16,830 44,940 16,620 20,250 942,360 981,010 1940 226,490 250,000 344,140 324,860 571,100 347,500 54,160 10,760 2,020 11,310 15,010 129,0602,286,410 2,212,840 1941 115,450 219,000 260,080 279,590 662,680 534,440 224,060 30,490 8,190 7,040 37,560 161,5302,540,110 2,489,360 1942 164,810 142,430 148,710 336,990 471,990 597,580 253,440 30,160 3,280 5,050 86,410 92,8502,333,700 2,355,520 1943 246,320 163,760 371,920 385,170 494,530 352,890 140,900 24,800 5,210 11,600 15,630 20,9302,233,660 2,369,810 1944 42,730 80,410 135,220 164,620 455,800 267,180 87,630 11,200 2,360 9,120 89,050 81,3101,426,630 1,295,310 1945 55,600 304,840 164,410 284,260 455,070 462,260 163,060 16,760 0 60,310 98,300 207,7402,272,610 2,085,740 1946 118,910 69,890 155,800 347,840 488,510 264,550 56,170 7,930 3,360 16,070 64,000 76,7201,669,750 1,879,310 1947 41,880 80,220 136,060 192,220 352,500 110,750 20,880 0 2,880 38,200 28,160 17,1801,020,930 1,094,180 1948 39,700 25,860 73,010 221,050 436,250 433,760 87,730 5,170 2,480 5,150 8,210 17,7701,356,140 1,408,550 1949 19,900 39,120 123,240 318,250 436,420 240,370 29,470 4,510 3,720 3,920 14,220 13,4201,246,560 1,246,130 1950 77,460 124,320 128,310 329,130 467,440 319,390 62,240 6,510 0 24,440 521,560 508,9902,569,790 1,546,360 1951 159,240 138,910 168,700 253,810 372,860 256,730 60,100 9,570 270 9,020 30,850 121,4101,581,470 2,475,180 1952 218,690 147,760 239,840 466,420 791,330 594,180 291,860 54,090 16,910 8,670 11,860 53,0602,894,670 2,982,360 1953 145,090 63,530 106,650 269,600 259,520 414,410 169,820 17,790 5,400 7,330 17,170 24,2001,500,510 1,525,400 1954 41,890 101,380 213,200 349,170 447,550 185,140 37,920 3,080 1,150 4,060 15,380 49,9901,449,910 1,429,180 1955 66,700 61,170 82,400 143,950 366,450 292,180 39,300 920 1,200 3,970 12,960 649,6201,720,820 1,123,700 1956 431,300 156,100 178,530 281,790 559,660 581,820 244,240 40,680 12,170 21,370 24,260 24,2002,556,120 3,152,840 1957 35,040 123,750 153,540 172,500 379,990 404,980 67,160 8,740 2,040 11,300 18,390 48,0301,425,460 1,417,570 1958 58,120 176,740 256,770 425,000 761,400 579,220 231,900 54,870 16,630 5,890 5,830 5,2302,577,600 2,638,370 1959 78,640 116,210 119,020 224,040 231,480 138,830 18,220 1,500 44,720 5,320 9,530 12,300 999,810 989,610 1960 25,200 119,380 149,500 238,390 303,410 162,350 16,060 5,800 5,140 5,390 15,660 32,6901,078,970 1,052,380 1961 18,660 46,550 71,390 164,820 219,810 122,310 18,760 12,510 3,840 5,000 8,030 23,690 715,370 732,390 1962 23,870 233,310 139,020 389,030 362,480 445,580 116,890 14,060 4,990 17,280 8,750 29,4501,784,710 1,765,950 1963 93,090 308,730 112,200 247,530 533,660 463,440 179,130 31,870 16,030 17,680 104,940 48,0202,156,320 2,041,160 1964 53,550 51,800 75,270 169,190 323,070 225,030 41,220 12,350 8,160 8,850 52,250 517,1401,537,880 1,130,280 1965 288,700 141,060 140,880 326,030 448,980 476,530 227,610 87,410 22,930 7,440 129,570 88,8502,385,990 1966 77,750 74,930 146,420 298,540 354,860 86,350 22,320 9,310 9,760 7,080 67,330 221,6001,376,250 1,306,100 1967 134,970 115,040 306,310 289,540 648,920 743,530 472,500 77,530 20,260 9,940 11,140 31,6202,861,300 3,104,610 1968 47,230 134,490 122,790 187,490 287,670 141,010 18,660 10,030 4,560 12,660 80,850 81,2601,128,700 1,006,630 1969 577,550 286,000 263,460 489,690 960,270 716,380 316,150 54,810 13,180 38,510 39,310 112,2903,867,600 3,852,260 1970 408,401 134,261 191,575 161,494 410,581 336,311 95,259 22,778 11,611 10,708 86,508 123,2631,992,750 1,962,381 1971 120,518 94,171 146,321 194,344 348,928 418,237 110,670 19,622 9,844 6,181 34,871 76,5421,580,249 1,683,134 1972 59,357 78,033 181,513 155,728 344,130 219,544 28,337 11,399 10,977 11,383 36,095 86,2471,222,743 1,206,612 1973 139,557 186,063 173,431 259,406 655,184 400,351 57,348 19,710 5,921 17,349 171,392 136,4592,222,171 2,030,696 1974 179,857 68,703 228,524 273,856 560,604 441,592 122,525 28,530 9,509 14,696 12,097 35,3511,975,844 2,238,900 1975 53,853 144,319 224,186 176,275 582,040 596,315 151,335 27,588 14,616 70,108 55,730 31,6282,127,993 2,032,671 1976 7,882 37,803 70,677 99,529 208,988 39,626 14,404 20,664 13,559 12,105 8,503 3,370 537,110 670,598 1977 10,740 17,451 23,278 78,883 105,985 104,636 11,516 3,217 2,977 1,632 11,685 96,248 468,248 382,661 1978 189,911 195,757 331,027 353,550 601,599 663,082 315,794 60,559 82,155 12,325 29,496 33,0862,868,341 2,902,999 1979 153,677 151,480 238,925 260,239 626,235 314,832 66,625 17,080 9,644 29,209 42,254 49,3671,959,567 1,913,644 1980 532,139 394,146 221,193 312,976 497,417 538,735 346,614 58,826 22,257 11,252 8,336 25,7752,969,666 3,045,133 1981 48,161 63,489 125,911 243,170 328,483 151,210 21,814 19,142 8,773 29,096 173,742 220,2451,433,236 1,055,516 1982 227,881 388,399 339,749 660,325 693,110 566,805 322,582 79,983 103,860 152,862 176,231 244,6063,956,393 3,805,777 1983 261,243 327,834 560,146 303,525 695,9331,016,194 629,625 205,170 58,030 43,833 310,276 402,1904,813,999 4,631,399 1984 175,424 150,674 199,589 202,815 535,744 329,550 92,967 21,172 6,534 26,106 85,226 48,2361,874,037 2,470,768 1986 129,323 616,493 492,540 319,713 540,315 506,647 144,170 30,006 17,643 18,326 8,274 13,1302,836,580 2,970,896 1987 6,352 37,076 88,982 194,340 203,457 64,654 10,193 8,082 2,725 10,666 26,144 50,314 702,985 655,591 1988 70,422 57,053 104,925 159,417 212,874 98,221 23,503 6,396 915 3,554 21,228 26,609 785,117 820,850 1989 36,544 61,500 285,046 309,418 320,768 207,394 28,061 2,106 9,679 48,807 24,878 21,6441,355,845 1,311,907 1990 38,235 52,727 129,680 220,291 181,713 100,254 20,080 3,600 682 1,249 8,477 4,504 761,492 842,591 1991 4,977 8,149 167,738 179,569 335,932 295,465 67,290 18,991 6,738 15,712 25,216 17,9341,143,711 1,099,079 1992 25,329 92,880 114,853 230,294 189,424 46,305 59,231 13,795 4,047 10,431 14,271 45,928 846,788 835,020 1993 278,432 161,069 319,015 334,965 630,922 524,051 225,810 53,823 24,843 18,787 7,484 18,4182,597,619 2,623,560 1994 21,904 53,241 108,309 195,219 275,062 118,698 32,885 25,176 9,502 10,217 64,214 57,836 972,263 884,685 1995 347,701 160,230 578,656 384,947 658,899 810,870 651,643 161,589 35,003 12,041 7,169 71,5643,880,312 3,921,805 1996 129,492 347,688 289,540 323,424 576,285 389,269 132,903 26,072 10,870 8,112 111,871 387,1372,732,663 2,316,317 19971,033,397 170,075 231,657 276,654 541,541 335,830 57,012 49,118 21,295 10,250 18,134 34,9872,779,950 3,223,699 1998 202,111 358,314 353,689 351,279 476,635 854,947 559,117 83,544 35,323 20,570 48,462 67,7483,411,739 3,338,330 1999 135,958 252,085 170,848 261,996 568,878 436,082 109,393 35,311 20,075 11,161 17,090 10,1272,029,004 2,127,406 2000 131,569 276,976 252,878 334,173 539,373 321,669 70,378 35,487 18,367 17,018 16,770 22,1592,036,817 2,019,248 2001 31,936 59,944 179,254 226,866 407,945 55,237 12,356 1,840 2,299 4,022 39,604 93,1231,114,426 1,033,624 2002 108,717 79,476 141,421 301,344 371,721 223,295 24,307 8,268 6,172 28 68,924 69,1191,402,792 1,401,470 2003 89,266 64,967 123,601 218,261 520,406 372,393 55,418 29,801 14,910 5,290 13,433 81,9671,589,713 1,627,094 2004 70,412 109,926 256,982 264,345 317,855 147,694 32,660 13,385 7,174 53,934 54,559 71,1051,400,031 1,321,123 2005 259,683 192,224 325,003 305,021 836,862 588,840 257,935 39,897 20,893 14,682 16,323 248,3953,105,758 3,005,956 2006 247,956 154,173 295,785 609,828 816,371 649,434 207,553 37,040 15,370 10,930 18,748 29,3013,092,489 3,312,910 2007 28,003 94,068 147,059 174,930 251,252 61,471 14,872 10,338 7,696 6,859 7,035 18,032 821,615 848,668 2008 77,731 100,736 123,659 188,561 360,341 203,979 32,469 4,989 4,401 4,312 61,501 27,4561,190,135 1,128,792 2009 107,965 115,404 231,165 261,458 564,834 224,025 59,140 15,673 6,388 56,344 10,585 40,4691,693,450 1,679,321 2010 90,140 105,834 159,640 247,578 384,421 623,112 140,844 13,441 8,755 108,837 80,573 334,2182,297,393 1,881,164 2011 173,387 137,561 416,854 431,888 516,538 775,690 446,577 81,111 25,890 37,436 18,211 4,9843,066,129 3,529,124 2012 48,983 31,594 110,276 291,315 250,804 62,416 17,005 11,293 6,222 2,455 39,088 185,4691,056,920 890,540 2013 73,463 52,730 128,231 238,350 241,669 97,759 21,357 9,208 5,618 4,410 4,636 6,143 883,575 1,095,398 2014 6,651 54,826 92,271 179,662 194,823 50,703 11,189 5,585 7,495 4,044 8,606 64,036 679,891 618,396 2015 23,532 112,963 58,464 87,769 144,333 60,765 16,423 4,035 4,891 14,196 37,122 102,138 666,631 589,861 From: aeboken
To: Hood, Donna
Subject: One way to help heal Central Valley while correcting political favoritism Date: Sunday, June 12, 2022 12:53:42 PM
CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe.
Hi Donna,
I'll be commenting on this article during General Public Comment at the SFPUC Commission meeting on June 14, 2022.
https://news.yahoo.com/one-way-help-heal-central-110000747.html Best,
Eileen Boken
Coalition for San Francisco Neighborhoods
Sent from my Verizon, Samsung Galaxy smartphone
June 28, 2022
Mr. Anson Moran, President
San Francisco Public Utilities Commission
Re: Commendation upon the retirement of Michael Carlin
Dear President Moran:
Restore Hetch Hetchy recognizes the extraordinary service that Deputy General Manager Michael Carlin has provided to the San Francisco Public Utilities Commission and its retail and wholesale customers for the past 26 years.
Mr. Carlin has served with integrity and diligence. He has led with exceptional humility and is highly respected by his colleagues at the SFPUC as well as by his peers at water agencies throughout the state.
Mr. Carlin has also respected the public interests who advocate for fundamental changes at the SFPUC. Restore Hetch Hetchy does believe the Commission should invest in system improvements that would allow Hetch Hetchy Valley to be restored to its natural splendor for the benefit of wildlife and visitors to Yosemite National Park; after all, Hetch Hetchy Reservoir remains, after 99 years, as the greatest intrusion into any of America’s national parks. While we regret that Mr. Carlin has staunchly defended the status quo, we appreciate that he has treated our ongoing campaign for restoration with dignity.
Providing reliable water supply (and power, sewer, etc.) to our homes and businesses is an essential public service that is often overlooked. Restore Hetch Hetchy values the work of both the Commission and the Bay Area Water Supply and Conservation Agency.
Today, we recognize Michael Carlin for his service. Thank you, Michael, and Godspeed.
Sincerely
Spreck Rosekrans
Executive Director
BOARD OF DIRECTORS
Roger Williams, Chair
Virginia Johannessen, Vice- Chair
Peter Van Kuran, Treasurer
Mark Palley, Secretary
Kathy Bowler
Mark Cederborg
James Fousekis
Ann Hayden
Rex Hime
Lance Olson
Craig Reynolds
Lucho Rivera
Mecia Serafino
Ron Sundergill
Melanie Webber
STAFF
Spreck Rosekrans
Executive Director
Julene Freitas
Office Manager
Mike Gaffney
Community Outreach Liaison
Tiffany Rosso
Director of Development
3286 Adeline St. Suite 7
Berkeley, California 94703
510.893.3400
Tax ID # 77-0551533
OFFICES
San Francisco
Modesto
Sonora
Mailing Address
P.O. Box 3727
Sonora, CA 95370
Phone
(415) 882-7252
Website
www.tuolumne.org
BOARD MEMBERS
John Kreiter, Chair
Harrison “Hap” Dunning,
Vice Chair
Cindy Charles, Treasurer
Kerstyn Crumb, Secretary
Eric Heitz,
Chair Emeritus
Jose Borroel
Eddie Corwin
Bob Hackamack
Camille King
Marty McDonnell
Homero Mejia
John Nimmons
Eric Riemer
Marek Robinson
Bart Westcott
June 13, 2022
President Anson Moran and Commissioners
SFPUC
525 Golden Gate Ave.
San Francisco, CA 94102
Via Email
Dear President Moran and Commissioners:
It’s time for San Francisco to establish an independent “January 7 Committee” to investigate whether SFPUC staff has been withholding information from you and the public.
You will recall that on January 7 two Commissioners requested information comparing historic demand projections from the Water Enterprise and Finance Division, along with actual demand. The aim was to determine which division has been more accurate over time. More than five months have passed, and staff has yet to produce this relatively simple document.
For more than seven months, environmental and fishing groups have requested information related to the Long-Term Vulnerability Assessment (LTVA). Numerous written and oral requests have gone unanswered. Of particular interest to us has been the return period (likelihood of occurrence) of the Design Drought. This is critical information the Commission will need when deliberating on whether it is prudent to remove a year from the Design Drought.
Two weeks ago, in response to a Sunshine Ordinance request, we received a document titled
“Hydrological Drought Frequency Analysis for the Upper Tuolumne River,” dated December 8, 2020. The document clearly demonstrates that a considerable amount of time was spent determining the projected return period of the Design Drought. Yet this information never made it into the LTVA.
The following table was included in the presentation.
2 The following graph from the uncovered document shows water supply deficits (from full storage) caused by known droughts. At full storage, the SFPUC has more than 1.4 million acre- feet of water. We have not been given a presentation on the document, but assume the graph suggests that if the historical record were to repeat, and water demand was 227 mgd (the baseline figure used in the LTVA, which is 16% higher than current demand of 195 mgd), a repeat of the most severe drought (1987-92) would result in full storage being reduced by 797 thousand acre-feet.
Below, TRT added the Design Drought to the graph for comparison.
It is clear that the Design Drought is extremely unlikely to occur. We hope you will be more assertive in directing staff to respond to information requests, both from you and the public.
Thank you for your attention to this matter.
Sincerely,
Peter Drekmeier
Policy Director
Hydrological Drought Frequency
Analysis for the Upper
Tuolumne River
December 8th, 2020
Design Drought: it’s an hydrological drought
Design Drought is a synthetic event that combines two observed droughts 1987-1992 followed by 1976-1977
Defining Deficit and Drought
• Definition of Annual Deficit
𝑑𝑑 𝑡𝑡 = La Grange Natural Flow(𝑡𝑡) − District Entitlement(𝑡𝑡) − 𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓 • Definition of Cumulative Annual Deficit
𝐷𝐷 𝑡𝑡 = 0 = 0
𝐷𝐷 𝑡𝑡 + 1 = min � 0
D t + La Grange Flow(t) − District Entitlement(t) − 𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓𝐓 • Threshold
• So far, we used SJPL Flow in 2013 of 240 MGD (269 TAF) as the baseline diversion needed for SFPUC (highe
st historical value)
• Extract the ma ximum deficit and duration in each drought What threshold do we want to use?
Threshold to define hydrological drought
The threshold can be based on:
• WAC: average
• SJPL diversion: average, maximum
• Other
Historical SJPL annual diversion
1 mgd = 1.12 TAF/year
Methodology
1. Run Up Country hydrology models for 500 climate realizations
2. Extract maximum deficit and duration of drought events from ob
served and simulated streamflow (Sequent Peak Algorithm)
3. Calculate return period
1. Fit two probability distribution for: maximum deficit and duration
2. Define a copula function that represents the dependence structure of defi
cits and duration
3. Calculate return periods
Application of Maximum Deficit to La Grange observed streamflow “historical mean demand” = historical irrigation district entitlement + 269TAF -450
-400
-350
-300
-250
-200
-150
-100
-50
0 Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7
Cumulative deficit
Duration
Cumulative
deficit
Extract drought events in historical records (95 years) 1976-77 1987-92 2012-16
Extract drought events in paleo record (1100 years)
Bias correction of paleo record based on error in historical record
Extract annual WAC in paleo record
Simulated streamflow using a weather generator and
hydrologic model
• Weather generator trained on pr ecip
and temp data from 1956-2011 for 13
gage stations
• 15-year periodicity to precipitation was
in
cluded (but unexplained in the
literature)
• (500 + 9) realizations x 50 years =
25 ,450 years
Extract drought events in the simulated data
Joint Return Periods of Deficit and Duration
• Three sources of hydrological data:
1) 95-year-lo ng historical natural flow at La Grange (1921 -2015) 2) 9 representative climate realizations of 50-y ear long streamflow simulated using PRMS model plus 500 other stochastic realizations using PRMS 3) paleo record at La Grange reconstructed from tree rings for the period 900-2012. • Total number of drought events identified by the SPA is 3,490:
1) 18 f
rom the historical streamflow
2) 3,316 from the PRMS streamflow realizations
3) 156 from the paleo streamflow
• Fitting probability distributions to deficit and duration. • Frank Copula for copula-based bivariate frequency analysis Fitting probability distribution for Deficit
Fitting probability distribution for Duration
Return periods of historical drought
Return periods of historical drought
Return periods of historical drought
Drought
Event
Deficit
(TAF)
Duration
(Year)
Return Period (Year)
(best estimate and 95% confidence interval)
Deficit Duration Deficit and
Duration
1976-77 517 2 217
(188; 255)
30 (29; 31)
316
(273; 371)
1987-92 797 6 1,456
(1,031; 2,140)
486
(422; 563)
20,406
(14,589; 29,851)
2012-16 752 4 1,093
(820; 1,520)
121
(110; 133)
4,250
(3,190; 5,899)
Design Drought 1,309 8 25,293
(12,940; 56,679)
1,954
(1,620; 2,376)
1,371,578
(720,390;
2,997,390)
Change in Return Period with Climate Change
500-year Return Period 1000-year Return Period
From: Dave Warner
To: Hood, Donna
Subject: My public comments for the record
Date: Tuesday, June 14, 2022 1:55:33 PM
Attachments: SFPUC Public comment 2022-06-14 Governance.pdf CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe.
Hi Donna,
Thanks for all your support and work for the commission meetings.
Attached is a copy of my public comments at today's meeting.
Best regards,
Dave
SFPUC Public Comment 2022-06-14
I’m Dave Warner from Palo Alto. I’m going to speak about governance.
I was shaken from the results of Mr. Drekmeier’s last Public Records Act (PRA) request. The PRA provided a detailed analysis on the frequency of the design drought, something that’s been requested many times, going back at least two years. To my understanding, not even commission president Moran had seen the analysis. Supposedly staff hadn’t shared the analysis because of data quality issues as described in an undated memo to file. But even the memo to file had a wealth of information. It’s bad news when a PRA provides significant information that previously hadn’t been disclosed.
This brings me to governance. We have an outstanding set of commissioners. You each are highly talented and bring valuable expertise and views to the commission. You also work remarkably well together.
Not to put words in your mouth, but I think you would say that a public agency such as the SFPUC should be transparent, unbiased and responsive.
This is where the problem is. As hard as it is for me to say this because of my admiration for you, you have little ability to oversee and influence staff.
The PRA is a glaring example of a transparency problem. You as commissioners should have had prior knowledge of what was provided and it shouldn’t have been a surprise to you or the public.
The list and age of open items you have with staff reflects the responsiveness problem. When I’ve served Boards of Directors, the expectation is that Board requests are resolved quickly, not measured in months or quarters.
My request of you is problem recognition. Is staff’s level of transparency a concern? Is bias a concern? Is responsiveness a concern? Most importantly, does staff reflect the values you think are important for a public institution and have you been able to influence the SFPUC’s behavior? I have high hopes for the new sheriff in town, GM Herrera. But even so, if you agree with the problem, direct, frank discussion needs to be had, with expectations understood.
Thank you. I will provide a copy of my comments for the record.
From: David Romano
To: Board of Supervisors, (BOS); Commission, Recpark (REC); [email protected]; Commission Cc: SFUN - San Franciscans for Urban Nature
Subject: The fight for a starry night
Date: Tuesday, June 21, 2022 8:41:05 AM
CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe.
Dear Supervisors and Commissioners,
When next you are considering putting more lights in public spaces, or making public policy regarding lighting, please take the natural world into account.
The
following quotations help provide context for the importance of this issue. “Remember to look up at the stars and not down at your feet,” advised the brilliant physicist Stephen Hawking, encouraging us to be curious and find sources of inspiration. The night sky has long served as a source of myth and mystery for the human species, something everyone, from rich to poor, could share and revel in.
But in recent times, with electric lighting spreading across the planet, the stars are becoming a rarer sight. Eighty percent of Americans see only murky darkness when they look up at the stars – for them, the Milky Way is obscured by light pollution.
This affects us, and the species around us, in many more ways than we can imagine.
But
more and more, cities and towns across the country are doing something about this loss of the night sky. Silverton recently passed a resolution for the town to switch to lower-Kelvin lighting in order to decrease light pollution. Durango has had a dark sky ordinance in place for nearly two decades. But what do regulations like this mean for the community? How successful have they been? We consulted some local experts to find out.
Protecting the nocturnal world
Bettymaya Foott, director of engagement for the International Dark-Sky Association, stressed that light pollution does more than ruin a pretty view of the stars. “Think about adding artificial light to a habitat as the equivalent of bulldozing a rainforest,” she said, reminding us that every species is impacted by it in some way.
Many birds, for instance, use stars, moonlight and other “celestial cues” to migrate overnight, said Foott. When they see a brighter, closer artificial light, they are drawn to it instead, leading them to lose their sense of direction. In their confused state, they are vulnerable to predators and other dangers that they wouldn’t normally have to face. The same goes for moths, which use the moon as a guide in nature. While the moon is a reliable beacon that moves in a predictable manner, our lights are not – moths can circle street lights for hours, thinking they are flying in a straight line.
On the coast, light pollution also confuses creatures like sea turtles, an already endangered species, which follow the sun and moon when nesting and hatching.
Bright, artificial lights and human presence can scare mother sea turtles away from nesting spots. After hatching, baby sea turtles usually follow the reflection of moonlight on the ocean. Now, they instead can be lured by city lights inland, toward countless dangers.
Too much artificial light at night is also doing us humans more harm than good.
According to an article by the Dark-Sky Association, circadian cycles are disrupted by too much light, especially blue light, which at night tricks our bodies into thinking it’s daytime. This leads to insomnia and a decrease in melatonin production, causing a whole host of additional problems and increasing the risk of everything from anxiety and depression to cancer. Blue light isn’t just coming from screens, either. Lit-up advertising and overly bright public lighting also emit it. - The fight for a starry night by
Elizabeth Barrett - 05/19/202, The Durango
Telegraph
----------------------
During migration season, millions of birds fly though Oregon as they head north for the summer. “We’re talking about songbirds, we’re talking about waterfowl, we’re talking about birds of prey,” said Portland Audubon conservation director Bob Sallinger. Most of their journey happens after the sun goes down. “You can’t see them at night, but the sky is literally full of birds,” Sallinger said Portland Audobon shared a “lights-out alert” on Tuesday, based on data published by Colorado State University’s AreoEco Lab. The lab forecasts bird migration patterns across the country and suggests varying levels of lights-out alerts based on how many birds are passing overhead. “Light has serious impacts on migration,” Sallinger said. “A lot of birds migrate at night and it blocks out the stars. They use the stars to navigate.”
Light pollution can disorient birds, causing them to exhaust themselves. It also can draw them into urban areas where they can face hazards, like crashing into windows. “Having people reduce unnecessary lighting during migratory periods does help,” Sallinger said. “That can be as simple as shutting off your porch lights and your outside lights at night.”
- Oregonians asked to turn off lights as millions
of migrating birds head north by Alex Hasenstab (OPB)
Thank you for your consideration of the above.
David Romano
San Francisco, CA
Bay Area Water Supply & Conservation Agency
June 22, 2022
Mr. Michael Carlin
Deputy General Manager and Chief Operating Officer
San Francisco Public Utilities Commission
525 Golden Gate Avenue, 13th Floor
San Francisco, CA 94102
On behalf of the Bay Area Water Supply and Conservation Agency, its 26 member agencies, and their water customers in Alameda, Santa Clara, and San Mateo Counties, I want to express our appreciation for your nearly three decades of service to the San Francisco Regional Water System that we all rely upon.
During your time at the San Francisco Public Utilities Commission (SFPUC), you were instrumental in efforts that have resulted in the Regional Water System being rebuilt to withstand a major credible earthquake and a robust Water Enterprise Capital Improvement Program designed to ensure that the Regional Water System will continue to provide a reliable water supply well into the future .
You and I have worked together for over twenty years serving this Regional Water System and its water customers. During this time and given our respective roles, there have been times where we have been on opposite sides of an issue. However, I have never questioned your dedication to public service and your loyalty to the Regional Water System . I appreciate having worked with you, and the BAWSCA region is grateful for your service .
We congratulate you on your upcoming retirement and wish you well in your new endeavors and good health for many decades to come.
( /J~ ' ~ 4/Y
1 Ncol
C
cc: SFPUC Commission
BAWSCA Board of Directors
155 Bove! Road, Suite 650 • San Mateo , CA 94402 • ph 650 349 3000 • fx 650 349 8395 • www.bawsca .org