NODOSSacramento River Sediment Transport Characteristics-

Implications for NODOS River Diversions to Sites Reservoir

North Of Delta Offstream Storage

• November through March diversions from the Sacramento River. Diversions will occur when sediment and flows are high.

• Three diversion points in the present formulation, the TCCA, GCID, and New Delevan Pipeline and Pumping Plant. Delevan will both divert water from river and release water when needed.

LOCATION MAP OF THE UPPER SACRAMENTO VALLEY

PROPOSED DIVERSIONS TO SITES RESERVOIR

OUTLINE

• TYPES OF SEDIMENT• SEDIMENT SOURCES• SACRAMENTO RIVER SEDIMENT

CHARACTERISTICS• PROPOSED DIVERSIONS• SYNOPTIC SAMPLING PROGRAM• SEDIMENT IN PROPOSED SITES DIVERSIONS

SUSPENDED SEDIMENT LOAD AND BEDLOAD

“Suspended load is the amount of sediment transported in suspension. It is separate from bedload, which moves along

the bottom. The amount of suspended sediment is dependent on the sources, and the ability of the river to

maintain the sediment in suspension. On the Sacramento River, the relation between streamflow and suspended

sediment is mostly due to dams and watershed characteristics and not carrying capacity. Bedload is

dependent on the ability of the stream to transport the particle sizes in the streambed.”

BEDLOAD

• May deposit at the entrance.• May plug or cover fish screens.• May divert streamflow and cause the river to

meander away from the intakes.• Ongoing problem at the GCID and M&T

facilities.

SUSPENDED LOAD

• Enters the forebay, where some of the load deposits.

• Most of the suspended sediment will go through the pumps and deposit in afterbays, canals, and reservoirs.

SUSPENDED SEDIMENT SOURCES

• RESERVOIR OUTFLOW• TRIBUTARY WATERSHEDS• SACRAMENTO RIVER BANK EROSION

SACRAMENTO RIVER SEDIMENT CHARACTERISTICS-

WARNING!!!!!!!

• SUSPENDED SEDIMENT CURVES ALL SCREWED UP

• ABNORMAL SUSPENDED SEDIMENT TRANSPORT

• POOR CORRELATIONS BETWEEN FLOW AND SUSPENDED SEDIMENT PRIMARILY DUE TO DAMS AND BANK EROSION

• SHASTA AND KESWICK ON THE SACRAMENTO RIVER• WHISKEYTOWN ON CLEAR CREEK• BLACK BUTTE ON STONY CREEK• OROVILLE ON THE FEATHER RIVER• ENGLEBRIGHT ON THE YUBA• NEW CAMP FAR WEST ON BEAR RIVER• FOLSOM ON THE AMERICAN

SEDIMENT CHARACTERISTICS-LARGE DAMS

SEDIMENT CHARACTERISTICS-TRIBUTARY WATERSHEDS

• SEDIMENT IN RIVER PRIMARILY FROM UN-DAMMED TRIBUTARIES

• HUMAN ACTIVITIES SUCH AS LAND USE, ROADS, MINING, TIMBER HARVESTING ETC.

• FLOODS AND FIRES• LANDSLIDE DE-STABILIZATION EVENTS• BANK STABILIZATION SUCH AS ROCK RIPRAP• EASTSIDE VERSUS WESTSIDE

SEDIMENT CHARACTERISTICS-EARLY SEASON STORMS

• LAKE SHASTA FILLING• TRIBUTARIES MAIN CONTRIBUTOR OF

SEDIMENT WITH MINOR DILUTION FROM RESERVOIR

• RIVER HAS HIGH SEDIMENT CONCENTRATION WITH LOW TO MODERATE FLOW

• MORE SEDIMENT ON RISING LIMB

SEDIMENT CHARACTERISTICS-MID-TO-LATE SEASON STORMS

• HIGH SEDIMENT CONCENTRATION ON RISING LIMB FROM TRIBUTARIES

• SEDIMENT-FREE SHASTA FLOOD RELEASES REDUCE FALLING LIMB SEDIMENT

DRY-NORMAL-WET YEARS

• DRY– NO DAM FLOOD RELEASES AND MINIMUM FLOWS FROM DAM. MINIMAL SEDIMENT IN RIVER.

• NORMAL- FLOOD RELEASES NEAR END OF SEASON. MODERATE SEDIMENT.

• WET- FLOOD RELEASES MORE COMMON. HIGH SEDIMENT IN RIVER FROM TRIBUTARIES AND BANK EROSION. LOW FROM DAM RELEASES.

ANNUAL FLOWSacramento River above Bend Bridge near Red Bluff, USGS 11377100

Annual Volume

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

1892

1895

1898

1901

1904

1907

1910

1913

1916

1919

1922

1925

1928

1931

1934

1937

1940

1943

1946

1949

1952

1955

1958

1961

1964

1967

1970

1973

1976

1979

1982

1985

1988

1991

1994

1997

2000

Water Year

Thou

sand

Acr

e-Fe

et

Period of Record:10/1/1891 - 9/30/2001

Drainage Area:8900 sq. mi.

Post-ShastaPre-Shasta

RESULT

• NEED TO KNOW THE SYSTEM• EXPECT LONG-TERM CHANGES• NEED TO ACCOUNT FOR SHASTA DAM

OPERATION• NEED TO KNOW THE TRIBUTARIES• SEDIMENT CHARACTERISTICS OF RIVER

CHANGES DOWNSTREAM

STUDY REACHSHASTA DAM TO COLUSA

SEDIMENT CHARACTERISTICS OF THE REDDING TO RED BLUFF REACH

• MUCH MORE sediment when dam releases are low and tributaries are flooding

• LOWER sediment when releases are high and tributaries subsided

• NEARLY Sediment-free releases during summer

• HUGE effect on sediment curves- poor correlation between flow and sediment

COTTONWOOD CREEKBut also Cow, Stillwater, Bear, Battle, Clear, not to mention

Paynes, Blue Tent, Dibble, Reeds and Red Bank that are below the Bend Gage.

COTTONWOOD CREEK MAJOR SEDIMENT CONTRIBUTOR

RED BLUFF TO COLUSA

• MORE COMPLEX SINCE IT IS AN ALLUVIAL STREAM WITH BANK EROSION WITHIN A MEANDER BELT

• FLOOD PLAIN DEPOSITION

• LEVEES

BANK EROSION

IMPORTANCE OF MOISTURE CONTENT

• MORE MOISTURE MEANS MORE WEIGHT• WATER LUBRICATES• WATER REDUCES SURFACE TENSION

BETWEEN CLAY PARTICLES• POSITIVE PORE PRESSURE AS RIVER RECEDES• RESULTS IN MORE BANK EROSION AND

MORE SEDIMENT ON FALLING LIMB

TRIBUTARY SEDIMENT CONTRIBUTIONRED BLUFF TO COLUSA

• EAST SIDE• ANTELOPE• MILL• TOOMES• DEER• PINE• BIG CHICO

• WEST SIDE• RED BANK• ELDER• THOMES- Another

major contributor• STONY CREEK- Dams

THOMES CREEK

“Thomes Creek has the highest sediment yield per unit area of any Sacramento Valley stream . In December 1964 it produced 67 million tonsIn a single storm event.”

CONVEYANCES FORPROPOSED PROJECT

• TCCA- 2,100 CFS• GCID- 1,800 CFS• DELEVAN- 2,000 CFS

TCCA RED BLUFF DIVERSION

• 2100 CFS TO SITES ALONG TEHAMA-COLUSA CANAL.

• NEW PUMPING PLANT, SCREENS, FOREBAY TO BE COMPLETED IN 2012 WITH 2,500 CFS CAPACITY. NO MORE RBDD.

• SEDIMENT IN DIVERSION MOSTLY FROM TRIBUTARIES, SOME WHICH ARE NOT GAGED.

• GREATEST EFFECT ON RIVER GEOMORPHOLOGY

USBR SEDIMENT STUDYTCCA DEPOSITION IN FOREBAY

GCID HAMILTON CITY DIVERSION

• 1,800 CFS TO SITES ALONG GLENN-COLUSA CANAL

• PROPOSED TERMINAL REGULATING RESERVOIR

• PRIOR WATER COMMITMENTS, BUT DIVERSION CAPACITY ABOVE 3,000 CFS

• SEDIMENT FROM TRIBUTARIES (THOMES CR.) AND BANK EROSION

GCID DIVERSION

DWR PROPOSED DELEVAN PUMPING PLANT

• 2,000 CFS THROUGH TWIN 12-FOOT DIAMETER PIPELINES TO FUNKS RESERVOIR.

• BEDLOAD AND SUSPENDED LOAD FROM TRIBUTARIES AND BANK EROSION

• POTENTIAL BEDLOAD PROBLEM• POTENTIAL MINOR MEANDER PROBLEM• LEAST EFFECT ON RIVER GEOMORPH

DELEVAN PUMPING PLANTCURRENT DESIGN

DELEVAN PUMPING PLANT SACRAMENTO RIVER MEANDERS

SYNOPTIC SAMPLING PROGRAM

• SINGLE DEPTH-INTEGRATED SAMPLES USING USGS D-48 SUSPENDED SEDIMENT SAMPLER

• 2001 TO 2003 STORM EVENTS SAMPLED• SAMPLED AT TCCA, GCID, AND DELEVAN

DIVERSION SITES• COMPARED TO USGS GAGING STATION DATA

PURPOSE OF SAMPLING

• COMPARE TO USGS GAGE DATA• SAME ORDER OF MAGNITUDE• MORE CONFIDENCE THAT GAGE DATA

REPRESENTS SEDIMENT CONDITIONS AT THE DIVERSION POINT

• ALL SAMPLES PLOTTED WITHIN THE ENVELOPE OF THE USGS GAGE DATA

“FIRST CUT MODELING ANALYSIS” SACRAMENTO RIVER SEDIMENT IN DIVERSIONS

• NO CALSIM II AVAILABLE• SIMPLIFIED ASSUMPTIONS• 10,000 CFS FLOW MUST REMAIN IN RIVER PAST DELEVAN BEFORE ANY

DIVERSIONS CAN TAKE PLACE• SACRAMENTO RIVER DIVERSION FLOW TO TCCA FIRST, THEN GCID, THEN

DELEVAN• SPREADSHEET CALCULATES MEAN DAILY SEDIMENT AT BEND BRIDGE,

HAMILTON CITY, AND BUTTE CITY • NOVEMBER 1- MARCH 31 DIVERSION PERIOD• 1964 TO 2007- 44 WATER YEARS OF DAILY DATA SIMULATED• CALCULATES SEDIMENT IN DIVERSION BASED ON FLOW SPLIT BETWEEN

RIVER AND DIVERTED AMOUNT• SEDIMENT CALCS BASED ON USGS SEDIMENT SAMPLING

MEAN DAILY CALCULATION OF DIVERSION FLOW AND SEDIMENT

          WINTER DIVERSIONS OF FLOW AND SEDIMENT FOR TCCA, GCID, AND DELEVAN

          NOVEMBER 1 TO MARCH 31      

          WATER YEARS 1964 TO 2007      

DATE BUTTE CITY TCCA TCCA GCID GCID DELEVAN DELEVAN TCCA GCID DELEVAN

  FLOW FLOW SEDIMENT FLOW SEDIMENT FLOW SEDIMENT NO DIVERSION NO DIVERSION NO DIVERSION

  CFS CFS TONS/DAY CFS TONS/DAY CFS TONS/DAY DAYS DAYS DAYS

11/1/1963 8000 0 0 0 0 0 0 1 1 1

11/2/1963 8000 0 0 0 0 0 0 2 2 2

11/3/1963 8000 0 0 0 0 0 0 3 3 3

11/4/1963 8000 0 0 0 0 0 0 4 4 4

11/5/1963 8240 0 0 0 0 0 0 5 5 5

11/6/1963 9500 0 0 0 0 0 0 6 6 6

11/7/1963 10000 0 0 0 0 0 0 7 7 7

11/8/1963 9240 0 0 0 0 0 0 8 8 8

11/9/1963 9500 0 0 0 0 0 0 9 9 9

11/10/1963 11300 1300 41 0 0 0 0 9 10 10

11/11/1963 10000 0 0 0 0 0 0 10 11 11

11/12/1963 8980 0 0 0 0 0 0 11 12 12

11/13/1963 8720 0 0 0 0 0 0 12 13 13

11/14/1963 8980 0 0 0 0 0 0 13 14 14

11/15/1963 11800 1800 103 0 0 0 0 13 15 15

11/16/1963 14000 2100 91 1800 213 100 17 13 15 15

11/17/1963 11600 1600 60 0 0 0 0 13 16 16

11/18/1963 10800 800 28 0 0 0 0 13 17 17

11/19/1963 10300 300 12 0 0 0 0 13 18 18

11/20/1963 16000 2100 172 1800 351 2000 418 13 18 18

11/21/1963 16800 2100 103 1800 255 2000 450 13 18 18

11/22/1963 12900 2100 93 800 90 0 0 13 18 19

11/23/1963 13700 2100 187 1600 260 0 0 13 18 20

11/24/1963 25200 2100 210 1800 644 2000 831 13 18 20

11/25/1963 20400 2100 121 1800 328 2000 603 13 18 20

11/26/1963 15400 2100 102 1800 243 1500 296 13 18 20

11/27/1963 13700 2100 96 1600 191 0 0 13 18 21

11/28/1963 12900 2100 96 800 90 0 0 13 18 22

11/29/1963 12100 2100 89 0 0 0 0 13 19 23

11/30/1963 11800 1800 74 0 0 0 0 13 20 24

12/1/1963 11600 1600 65 0 0 0 0 13 21 25

12/2/1963 11300 1300 53 0 0 0 0 13 22 26

12/3/1963 11100 1100 40 0 0 0 0 13 23 27

12/4/1963 10300 300 11 0 0 0 0 13 24 28

12/5/1963 10500 500 20 0 0 0 0 13 25 29

12/6/1963 10800 800 32 0 0 0 0 13 26 30

12/7/1963 10500 500 21 0 0 0 0 13 27 31

12/8/1963 11100 1100 49 0 0 0 0 13 28 32

12/9/1963 11300 1300 59 0 0 0 0 13 29 33

12/10/1963 11600 1600 71 0 0 0 0 13 30 34

12/11/1963 11300 1300 58 0 0 0 0 13 31 35

12/12/1963 11300 1300 57 0 0 0 0 13 32 36

12/13/1963 11600 1600 70 0 0 0 0 13 33 37

12/14/1963 11600 1600 70 0 0 0 0 13 34 38

12/15/1963 11600 1600 69 0 0 0 0 13 35 39

12/16/1963 11600 1600 69 0 0 0 0 13 36 40

12/17/1963 11600 1600 69 0 0 0 0 13 37 41

12/18/1963 11600 1600 69 0 0 0 0 13 38 42

12/19/1963 11300 1300 56 0 0 0 0 13 39 43

12/20/1963 11600 1600 71 0 0 0 0 13 40 44

12/21/1963 11600 1600 70 0 0 0 0 13 41 45

12/22/1963 11600 1600 67 0 0 0 0 13 42 46

12/23/1963 11100 1100 45 0 0 0 0 13 43 47

12/24/1963 11100 1100 43 0 0 0 0 13 44 48

12/25/1963 10800 800 32 0 0 0 0 13 45 49

12/26/1963 10800 800 33 0 0 0 0 13 46 50

12/27/1963 10800 800 33 0 0 0 0 13 47 51

12/28/1963 10800 800 31 0 0 0 0 13 48 52

12/29/1963 10500 500 18 0 0 0 0 13 49 53

12/30/1963 10500 500 18 0 0 0 0 13 50 54

12/31/1963 10500 500 16 0 0 0 0 13 51 55

OUTPUTS

• DAILY AMOUNT OF SUSPENDED SEDIMENT AT THE THREE GAGES AND IN DIVERTED FLOW AT TCCA, GCID AND DELEVAN

• DAILY DIVERTED STREAM FLOW AT EACH OF THE THREE DIVERSION SITES

• ANNUAL SEDIMENT IN DIVERSIONS• NUMBER OF DIVERSION DAYS

BEND BRIDGE

• DAM EFFECTS• TWO ORDERS OF MAGNITUDE• LOW ESTIMATE OF SEDIMENT

Sediment Concentration vs. Discharge, Sacramento River at Bend Bridge

y = 2E-05x1.47

R2 = 0.4419

1

10

100

1000

10000

1000 10000 100000 1000000

Discharge (CFS)

Con

cent

ratio

n (m

g/L)

USGS SEDIMENT SAMPLING BUTTE CITY• LOG-LOG SCATTER PLOTS• BEST FIT EQUATION• LIMITED DATA • DROUGHT• “POOR CORRELATION “• “ORDER OF MAGNITUDE”

Sediment Concentration vs. Discharge, Sacramento River at Butte City

y = 3E-05x1.5103

R2 = 0.7586

1

10

100

1000

10000

1000 10000 100000 1000000

Discharge (CFS)

Con

cent

ratio

n (m

g/L)

SIMULATED NODOS WINTER DIVERSIONSNOVEMBER 1 – MARCH 31, 1964 TO 2007

ANNUAL AVERAGES

WATER BUTTE CITY TCCA TCCA TCCA GCID GCID GCID DELEVAN DELEVAN DELEVAN TCCA TCCA GCID GCID DELEVAN DELEVAN YEAR FLOW FLOW SEDIMENT SEDIMENT FLOW SEDIMENT SEDIMENT FLOW SEDIMENT SEDIMENT DIVERSION NO DIVERSION DIVERSION NO DIVERSION DIVERSION NO DIVERSION

  CFS CFS TONS TONS/DAY CFS TONS TONS/DAY CFS TONS TONS/DAY DAYS DAYS DAYS DAYS DAYS DAYS                                 

1964 10731 841 6563 43 262 7601 50 159 8260 54 84 67 28 123 14 1371965 23400 1017 45330 300 807 87809 582 843 146149 968 77 74 69 82 67 841966 15860 1655 17982 120 1123 33515 223 756 41693 278 132 19 104 47 76 751967 21635 1490 34376 228 1099 66698 442 1042 106866 708 115 36 99 52 84 671968 16529 1096 19732 130 716 36774 242 618 58215 383 88 63 67 84 50 1011969 30906 1462 54649 362 1154 112748 747 1235 206334 1366 108 43 102 49 95 561970 34561 1516 98063 649 1250 161665 1071 1308 252984 1675 111 40 108 43 102 491971 24753 1634 42305 280 1293 81749 541 1335 130982 867 126 25 110 41 105 461972 11154 708 6571 43 346 10789 71 318 14193 93 63 88 34 117 24 1271973 28777 1851 41950 278 1518 94940 629 1516 168972 1119 138 13 128 23 125 261974 42198 2003 106551 706 1701 190169 1259 1881 301310 1995 144 7 144 7 142 91975 20360 1369 28168 187 791 57009 378 748 91373 605 108 43 71 80 65 861976 9942 710 5632 37 234 5079 33 74 2771 18 61 90 41 110 8 1431977 5387 7 30 0 0 0 0 0 0 0 1 150 0 151 0 1511978 23961 1232 34371 228 966 88843 588 952 146584 971 94 57 85 66 78 731979 10560 524 4628 31 326 13863 92 299 19877 132 45 106 30 121 24 1271980 27144 1355 53703 353 989 98866 650 926 176065 1158 104 47 92 59 73 781981 11670 610 7727 51 413 19174 127 383 27317 181 52 99 37 114 31 1201982 31108 1887 62290 413 1590 119974 795 1657 192983 1278 137 14 134 17 131 201983 48128 1819 142604 944 1419 236534 1566 1474 395805 2621 134 17 126 25 114 371984 27911 1801 48373 318 1323 101426 667 1317 163882 1078 140 11 116 35 104 471985 12437 730 9346 62 520 19925 132 547 28874 191 58 93 45 106 42 1091986 28371 972 73414 486 772 129323 856 820 212785 1409 75 76 65 86 64 871987 9476 371 2814 19 221 9101 60 189 12358 82 31 120 23 128 15 1361988 8790 391 3015 20 270 10221 67 239 13060 86 32 119 23 128 19 1321989 10053 500 4740 31 334 13102 87 303 18390 122 38 113 31 120 26 1251990 7086 129 861 6 63 1922 13 40 2388 16 12 139 7 144 4 1471991 6597 230 1277 8 152 5517 37 150 7319 48 17 134 13 138 12 1391992 8681 409 3995 26 288 11784 78 277 18417 121 31 120 26 125 21 1301993 20409 1154 28517 189 813 64705 429 840 111406 738 90 61 72 79 65 861994 7274 227 1047 7 130 2171 14 95 3674 24 20 131 13 138 8 1431995 35344 1228 89652 594 959 165508 1096 983 281821 1866 91 60 84 67 76 751996 17722 814 30412 200 635 56915 374 970 124213 817 62 89 54 97 52 991997 25729 1190 66306 439 895 123635 819 937 157194 1041 96 55 77 74 73 781998 39037 1385 94475 626 1096 189232 1253 1174 306727 2031 104 47 95 56 90 611999 24198 1576 38071 252 1238 72211 478 1311 123334 817 120 31 106 45 101 502000 24073 1055 49015 322 845 81364 535 865 147261 969 77 74 72 79 66 852001 9003 413 3395 22 256 9550 63 198 14383 95 34 117 24 127 17 1342002 13494 801 10336 68 497 21767 144 468 40582 269 69 82 46 105 38 1132003 19977 1321 23445 155 978 58784 389 959 96131 637 99 52 89 62 78 732004 23341 1343 45466 299 980 78872 519 930 132296 870 105 46 88 63 75 762005 11227 707 5414 36 480 14691 97 383 23869 158 58 93 45 106 33 1182006 30402 1440 69026 457 1154 122468 811 1230 199445 1321 105 46 100 51 94 572007 8556 264 2371 16 136 4726 31 97 5516 37 23 128 14 137 9 142

AVERAGE 19953 1028 34500 228 751 65744 435 747 107592 712 80 71 67 84 59 92

SUM     1518006     2892718     4734061   3509 3135 2937 3707 2590 4054

TCCA SUMMARY• Sediment mostly from tributaries• Sediment concentration dependent on where flows coming from• Early season storms have high sediment concentration• Rising limb of hydrograph carries more sediment• Late season storms may have clear water dam releases on the falling limb• Bank erosion not a major contributor to TCCA sediment• Ungaged Tributaries between Bend gage and TCCA have high sediment

yields. THESE DO NOT SHOW UP ON THE BEND GAGE!!!!• TCCA sediment probably higher than calculated• Moving the pumps above Red Bank Creek will help, but still have Reeds,

Dibble, Blue Tent, Paynes Creeks• Average flow to Sites during winter diversion 1028 cfs (310,000 AF)• Average number of diversion days is 80 out of 151.25.• Average annual sediment is 34,500 tons with a low of 30 (1977) to a high

of 143,000 (1983)

GCID SUMMARY• Bank erosion major contributor to sediment at GCID. • Bedload deposition at inlet may restrict winter flows. • Thomes Creek has very high sediment concentrations. Rising limb carries

more sediment.• Thomes has late season sediment from landslides in wet years that may

persist for several months.• Bank erosion sediment expected to be higher on falling limb for major

storm events.• Normally have 6 week downtime in winter for maintenance• Average winter diversion is 751 cfs (225,300 AF).• Average number of diversion days is 67 out of 151.25.• Average sediment is 65,750 tons, varying from 0 (1977) to 236,500 (1983).

DELEVAN SUMMARY• Sediment from bank erosion and tributaries• Dam effects reduced by tributaries, distance, and bank

erosion.• Sediment 3X higher than TCCA• High sediment yields should be a major factor in design of

Delevan diversion facilities• Average winter flow to Sites 747 cfs (224,100 AF) with a low of

0 (1977) and a high of 1881 (1974)• Average sediment to Sites is 108,000 tons, with a low of 0

(1977) and a high of 396,000 (1983).• Average number of diversion days is 59 out of 151.25.

SUMMARY AND CONCLUSIONS• Human changes have affected the balance between erosion and

deposition• Floods, fires, timber harvesting, and landslides dramatically change

sediment yields• Dams capture sediment and release flows with low sediment

concentrations. Dams also capture winter flow and release during summer.

• Sediment in diverted flow dependent on where flow is coming from• Tributaries have high sediment compared to reservoir releases • Sediment concentrations increase downstream• Sediment movement changes dramatically from year to year• Average annual winter diversion to Sites 2526 cfs (758,000 AF)• Average annual yield of three diversions is about 208,000 tons, with

a low of 30 (1977) to a high of 775,000.

RECOMMENDATIONS• SEDIMENT SHOULD BE A MAJOR CONSIDERATION IN DESIGN

OF FACILITIES WITH ENLARGED FOREBAYS• OPERATIONAL DESIGN SHOULD INCLUDE SEDIMENT

REMOVAL DURING WINTER OPERATIONS• VERY LARGE VARIATION IN AMOUNT OF SEDIMENT

ENTRAINED FROM YEAR TO YEAR REQUIRES A LARGE SEDIMENT STORAGE AREA.

• FLEXIBLE FINANCING IS NEEDED SINCE O&M COSTS WILL VARY HUGELY FROM YEAR TO YEAR

• SEDIMENT CONCENTRATION SHOULD BE USED AS A FACTOR IN FORMULATING WHEN DIVERSIONS OCCUR

NEXT STEP

• INTEGRATE LATEST NMFS BO AND OCAP INTO ANALYSIS

• USE LATEST CALSIM II (USRDOM) FLOW ANALYSES OF FUTURE CONDITIONS

• COORDINATE WITH USBR DENVER OFFICE

THE END