ENVS 202 Third Homework Assignment

Date Due: June 5

All about Dams and the Columbia river

A statistical comparison between the Dalles Dam and McNary Dam.

You have been assigned by your company, "Progress 'R Us", to study if there has been a decline in recent years of Salmon at McNary dam and if there is a mortality rate of fish between The Dalles Dam and McNary Dam. You have the following raw data from which to work with. When working with data like this its best to abbreviate it. So if you enter numbers into the the Tool don't be anal and put in a number of 126555 - just abbreviate that to 126 and remember that the units are thousands. It will save a lot of data entry time.

  YEARLY TOTALS OF SALMONIDS COUNTED OVER MCNARY DAM 1954-2002

 YEAR  CHINOOK* STEELHEAD  SOCKEYE    COHO*     TOTALS*

 1954    126,555    75,059   108,181       950    310,745
 1955    108,915    85,575   173,758       643    368,891
 1956    114,342    42,554   102,145       683    259,724
 1957    292,696   105,728    85,460     2,855    486,739
 1958    226,092    87,890   102,397     1,350    417,729
 1959    171,490   110,475    83,977     1,970    367,912
 1960    176,767    96,895    55,372     1,580    330,614
 1961    154,996   103,743    16,388     2,045    277,172
 1962    152,756   163,181    29,372     3,195    348,504
 1963    154,459   113,646    59,744     3,113    330,962
 1964    167,934   100,742    83,931     3,317    355,924
 1965    150,907   118,960    42,052     2,700    314,619
 1966    223,141   145,130   173,028     8,525    549,824
 1967    195,653    77,700   105,635    27,226    406,214
 1968    200,488   112,522   101,007    39,518    453,535
 1969    213,407    76,681    29,787    53,716    373,591
 1970    168,892    69,759    59,636    36,399    334,686
 1971    171,448   109,630    52,867    39,358    373,303
 1972    168,821    93,820    26,422    45,635    334,698
 1973    184,112    64,620    42,731    17,682    309,145
 1974    127,858    26,932    26,505    13,746    195,041
 1975    133,150    23,663    43,143     3,975    203,931
 1976    163,314    54,000    24,632     7,539    249,485
 1977    183,581    87,712    80,781     4,622    356,696
 1978    144,148    34,740    18,511    20,356    217,755
 1979     95,275    50,304    37,792    12,800    196,171
 1980     80,773    66,524    44,301       571    192,169
 1981     80,619    61,985    26,644     3,736    172,984
 1982    102,225    75,099    15,077     3,119    195,520
 1983    121,636   125,254    40,903     2,470    290,263
 1984    159,071   135,515    56,906     2,841    354,333
 1985    288,483   188,204    98,457     6,917    582,061
 1986    342,417   193,481    46,443     1,374    583,715
 1987    286,638   148,811    72,190       615    508,254
 1988    243,608   151,765    50,080     2,010    447,463
 1989    176,407   170,467    41,318     3,383    391,575
 1990    147,439    95,061    46,145     2,059    290,704
 1991    114,841   168,692    69,365     2,272    355,170
 1992    135,707   194,026    68,737     1,801    400,271
 1993    143,412    93,183    66,485       481    303,561
 1994    128,868    94,427    10,603     1,735    235,633
 1995    113,354   114,910     8,320     1,021    237,605
 1996    114,947   124,177    28,585     1,853    269,562 
 1997    162,946   129,817    38,043     2,580    333,386
 1998    114,604    99,705     9,391     6,173    229,873
 1999    121,946   101,799    11,794     4.935    240,474
 2000    191,070   161,135    60,242    12,178    424,625
 2001    489,784   493,168    97,188    24,918  1,105,058
 2002    417,090   368,244    39,424    13,313    838,071

 Counts for the Dalles Dam

 1957    312,678   129,361    90,201     6,793    539,112
 1958    301,960   121,420   111,039     2,395    536,850
 1959    207,461   156,090    86,259     2,709    452,553
 1960    196,962   111,189    59,441     3,000    370,632
 1961    201,335   134,572    16,689     2,139    354,739
 1962    187,132   163,301    27,127     3,696    381,261
 1963    180,969   118,957    56,931     3,716    360,599
 1964    183,842   110,033    79,042     5,978    378,900
 1965    195,049   141,052    44,279    17,468    397,852
 1966    240,671   146,172   147,886    32,279    567,009
 1967    280,112   121,614   120,589    32,015    554,335
 1968    262,975   147,481   116,897    42,687    570,041
 1969    314,258   112,529    37,226    17,054    481,068
 1970    261,457    99,187    77,678    23,219    461,545
 1971    250,528   151,348    76,103    29,061    507,043
 1972    268,628   135,303    44,671    16,562    465,164
 1973    280,945   100,082    52,303    11,152    444,483
 1974    217,181    70,875    28,827    14,655    331,538
 1975    217,283    57,675    43,198    13,976    332,132
 1976    216,163    82,568    27,747    19,392    345,870
 1977    224,950   133,882    86,252    10,021    455,105
 1978    199,228    60,485    11,845    18,877    290,435
 1979    150,647    83,364    32,791     8,726    275,532
 1980    113,951    93,963    42,088     6,326    256,328
 1981    135,176   113,268    35,447     6,941    290,833
 1982    172,682   117,434    33,331     7,383    330,830
 1983    156,190   171,055    84,204     3,459    414,909
 1984    203,920   219,123   101,177     3,142    527,363
 1985    370,982   276,025   117,254     4,625    768,891
 1986    443,013   281,953    48,477     4,842    778,292
 1987    421,190   217,768    87,599     3,310    729,870
 1988    378,080   198,499    55,802     9,226    641,607
 1989    282,168   235,639    39,672    12,611    570,090
 1990    207,556   129,271    40,230     4,645    381,702
 1991    153,023   199,853    63,405     9,601    425,985
 1992    168,507   232,179    66,384     3,825    470,898
 1993    184,953   124,829    62,252     4,360    376,394 
 1994    161,758   112,253     9,356     4,376    287,743 
 1995    141,793   145,844     7,166     3,269    298,072
 1996    167,911   162,456    25,055     4,583    360,005 
 1997    223,801   164,756    32,430     4,729    425,716
 1998    154,132   116,682     8,826     8,970    288,610
 1999    199,491   198,253    13,715    15,041    426,500
 2000    316,214   258,952    73,383    29,413    677,962
 2001    629,334   628,444   102,562    64,478  1,424,818
 2002    583,155   504,485    40,554    12,786  1,140,980 


A. Where are McNary Dam and the Dalles Dam located and how much power does they produce?

B. Compute the following for both dams:

From that, establish the following:

Are the counts at each dam in the period of 1990-1999 significantly lower than that seen in the period 1960-1989?

Average the 2001 and 2002 counts together. What is the probability that you would get salmon counts this high, given the mean and dispersion in the period 1960-1999. How might this result change the thinking about the Pacific Northwest Salmon problem?

C. Make a graph of Chinook counts vs steelhead counts by combining the two data sets. Are they correlated? If they are correlated, explain how this might simplify your data analysis. If they are not correlated, explain how this might complicate your data analysis.

D. Now look at the data carefully to see if you can identify any 5 year periods in which the Salmon counts at either dam were low compared to the average count in the 40 year period your derived above.

E. Located between the Dalles and McNary Dam is John Day Dam. If there is salmon loss due to John Day dam, then less fish should be counted, on average, at McNary Dam than at the Dalles. Use the data to try and determine the mortality rate (in terms of percentage of fish) of John Day Dam.

F. Based on your study of these two dams, write a press release in language that Joe Six pack can understand about what you conclude the effect of the dams are on salmon survival.

3. Currently there is a feasibility study about breaching the 4 Dams on the lower Snake River. What are some of the pros and cons associated with this procedure and would you support the breach or be opposed to it?

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