Fish Impinged at Basin Electric 

Leland Olds Station, GRE Stanton 

Station, and Minnkota M.R. Young 

Missouri River Station, Cooling 

Water Intake Structures

Final Data Summary

(June 2005 to June 2006)

Prepared by ENSR Corporation

August 2006
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 1

Fish Impinged at Basin Electric Leland Olds Station, GRE Stanton Station, 

and Minnkota M.R. Young Missouri River Station, Cooling Water Intake 

Structures

Final Data Summary

(June 2005 to June 2006)

Collection Periods

Samples were collected at two-week intervals unless interrupted by weather. For example, 

the regular collection events of October 5, 2005 were cancelled because of snow; the 

sampling event was rescheduled for, and completed on, October 10, 2005. In some cases, 

circumstances required that sampling be rescheduled at one site only. On April 7, 2006 data 

were collected at the Minnkota M.R. Young CWIS because there was a noticeable increase 

in the number of fish (36) collected on April 5 at Stanton and Leland olds relative to what had 

been collected on March 22 (12).

June 13-14, 2005 (M.R. Young Missouri 

River only)

June 15-16, 2005

June 28-29, 2005

July 12-13, 2005 

July 17-18, 2005 (M.R. Young Missouri River 

only) 

July 26-27, 2005

August 9-10, 2005

August 23-24, 2005

September 6-7, 2005

September 20-21, 2005

October 9-10, 2005

October 18-19, 2005

November 1-2, 2005

November 15-16, 2005

November 29-30, 2005

December 13-14, 2005

December 16, 2005 (GRE pm sample only)

December 27-28, 2005

January 10-11, 2006

January 24-25, 2006

January 25-26, 2006 (GRE am sample only)

February 7-8, 2006

February 21-22, 2006

March 7-8, 2006

March 21-22, 2006

April 4-5, 2006

April 7, 2006 (M.R. Young Missouri River pm 

sample only)

April 18-19, 2006

April 20-21, 2006 (GRE only)

May 2-3, 2006

May 16-17, 2006

May 30-31, 2006

June 13-14, 2006

June 27-28, 2006
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 2

Fish Collected

Because of the complete absence of fish in the collection basket at the Minnkota M.R. Young 

Missouri River CWIS during the first three months of the study, collection efforts were 

reduced at this facility. Data were collected at this facility at the end of the year (Dec. 28, 

2005), and no fish were found. No data were collected at the M.R. Young Missouri River 

CWIS during the first quarter of 2006. On April 5, 2006 36 fish were collected from Leland 

Olds and Stanton. While this isn’t an extremely large number of fish and no where near the 

number collected in late 2005, it did represent a substantial increase over the number 

collected on March 22, which was 12. Because of the increase in the number of fish 

collected, a PM event was scheduled at the M.R. Young Missouri River CWIS on April 7; no 

fish were collected. Additional collection events in 2006 at the M.R. Young Missouri River 

CWIS occurred on April 19 and June 14; no fish were collected on those dates.

After higher quantities of fish in June 2005, there was a drop in the number collected in the 

months of July and August at Leland Olds and Stanton. Beginning in September 2005, the 

number of fish increased and, through the rest of 2005,was similar to what was first observed 

in June of that year, with one exception (Figure 1). That exception was on November 30, 

when the total number of fish collected in the morning at Leland Olds and Stanton exceeded 

140 (combined) and the number of fish collected in the evening at the two stations exceeded 

100. Most of these fish were gizzard shad (Dorosoma cepedianum). In January 2006, the 

number of fish collected at Leland Olds and Stanton was similar to what was observed in the 

last few months of 2005. The January 11, 2006 event produced the second highest number 

of fish (after November 30, 2005), the majority of which were rainbow smelt (Osmerus 

mordax). 

The number of fish collected at Leland Olds and Stanton decreased substantially in February 

2006. For the first time since July and August 2005, no fish were collected during some 

events. On February 22, no fish were collected at Stanton and on March 8 only one fish was 

collected, an emerald shiner (Notropis atherinoides) at Leland Olds in the evening. On April 

5 a total of 36 fish were collected, which is a substantial increase from the previous events in 

March. Twenty-three of those fish were emerald shiners collected from Stanton and only 

seven fish, also emerald shiners, were collected from Leland Olds. This was the largest 

number of fish collected in the second quarter of 2006.

Throughout the entire collection period, morning samples tended to yield more fish than the 

evening samples, although there were exceptions. More fish were collected at Stanton than 

at Leland Olds.

The maximum number of species collected in the second quarter of 2006 was four. During 

the last three sampling events in late May and June 2006 only two species were collected on 

any one date (Figure 2). 
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 3

Figure 1. Total Number of Fish Collected at Leland Olds and Stanton 

through June 2006

0

10

20

30

40

50

60

70

80

June 13-17

July 12-13

Aug 9-10

Sept 6-7

Oct 9-10

Nov 1-2

Nov 29-30

Dec 27-28

Jan 24-25, 25-26

Feb 21-22Mar 21-22

Apr 18-19, 20-21

May 16-17

June 13-14

Sampling Period

N

u

m

b

er of Fis

h

Leland Old AM Collection

Stanton AM Collection

Leland Olds PM Collection

Stanton PM Collection

Figure 2. Number of Species Collected at Leland Olds and Stanton 

through June 2006

0

1

2

3

4

5

June 13-17

July 12-13

Aug 9-10

Sept 6-7

Oct 9-10

Nov 1-2

Nov 29-30

Dec 27-28

Jan 24-25, 25-26

Feb 21-22Mar 21-22

Apr 18-19, 20-21

May 16-17

June 13-14

Sampling Period

N

u

m

b

er of S

p

e

cie

s

Leland Olds AM Collection

Stanton AM Collection

Leland Olds PM Collection

Stanton PM Collection
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 4

Nineteen species were identified in the collection baskets at Leland Olds and Stanton over 

the entire collection period (Figure 3). One new species was found in the second quarter of 

2006. One yellow perch (Perca flavescens) was collected during the April 15 morning event 

at Stanton.

Figure 3. Species Collected at Leland Olds and Stanton Stations 

through June 2006

0

20

40

60

80

100

120

140

160

Smelt

Emerald Shiner

Black Bullhead

Gizzard Shad

Goldeye

Carpsucker

Tadpole Madtom

Walleye

Northern Pike

White Sucker

Fathead Minnow

Shortnose Gar

Longnose Sucker

Freshwater Drum

Channel Catfish

Saugeye

Common Whitefish

Stonecat

Yellow Perch

Species

T

otal N

u

m

b

er of In

divid

u

al Fis

h

Leland Olds AM Collection

Stanton AM Collection

Leland Olds PM Collection

Stanton PM Collection

Over the collection period, substantial species shifts were seen. From June 2005 through 

January 2006, the rainbow smelt was, with a couple exceptions, the most common species 

collected. From June through August 2005 the emerald shiner was the second most 

common species collected. Gizzard shad were first collected on August 24 (at Leland Olds) 

and was found during all events through mid-December (Figure 4; note that the number of 

shad collected on November 30 [220] has been truncated in this figure to better illustrate the 

other values). Gizzard shad was most common at Leland Olds in the evening events. During 

that same period, emerald shiner disappeared from the collection baskets entirely. On 

December 14, gizzard shad made its last appearance at Leland Olds in the evening sample. 

On that same date, the emerald shiner reappeared at both Leland Olds and Stanton in both 

the morning and evening sampling events. 

In January 2006 emerald shiners were present in samples from both Leland Olds and 

Stanton. The total number of fish was low in February and early March, but in late March 

emerald shiners emerged as the dominant species in the collection basket and remained the 

most common fish for the rest of the study period. Fathead minnows tended to be somewhat 
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 5

more common in the first quarter of 2006 and were the most common species in the June 14 

sample.

All of the species collected at Leland Olds and Stanton are presented in Table 1.

Figure 4. Total Number of the Six Most Abundant Fish Collected at 

Leland Olds and Stanton

0

20

40

60

80

100

120

June 16June 29

July 13July 27

Aug 10Aug 24

Sept 7

Sept 21

Oct 10Oct 19

Nov 2

Nov 16Nov 30

Dec 14/16

Dec 28

Jan 11

Jan 25/26

Feb 8

Feb 22

Mar 8

Mar 22

Apr 5/7

Apr 19/21

May 3

May 17May 31

June 14June 28

Collection Date

N

u

m

b

er of Fis

h

Rainbow Smelt

Emerald Shiner

Gizzard Shad

Fathead Minnow

Longnose Sucker

Channel Catfish

(Actual value = 220) 

Fish Metrics

In the second quarter of 2006, gizzard shad were not collected and smelt were found only at 

Stanton on April 5, May 3 and May 17. Of the three most common study species, only the 

emerald shiner remained at Leland Olds. The mean total length of emerald shiners was 

consistent between 6 and 8 cm (Figure 5). While the length of smelt showed an increase at 

Leland Olds in late December 2005 and early 2006, other species remained constant (Figure 

5). The total length of fish collected at Stanton also remained fairly constant during the 

collection period, with most fish measuring between about 6 and 8 cm (Figure 6). 

The mean weight of the three most common fish tended to show more variability than length. 

As with length, the mean weight of smelt collected at Leland Olds also increased in late 

December 2005 and early 2006 (Figure 7). Mean weight of emerald shiners in 2006 was 

similar to what was observed in summer 2005, before this species disappeared from the 
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 6

collection basket. All mean weights of smelt and emerald shiners collected in 2006 at 

Stanton were equal to or less than 4 g (Figure 8). 

Table 1. Species and number collected

Species Leland Olds Stanton

Rainbow Smelt 132 218

Emerald Shiner 50 89

Black Bullhead 1 4

Gizzard Shad 177 129

Carpsucker 1 8

Goldeye 1 2

Tadpole Madtom 2 0

Walleye 1 0

Northern Pike 0 1

White Sucker 1 1

Fathead Minnow 5 11

Shortnose Gar 1 0

Longnose Sucker 13 7

Freshwater Drum 3 0

Channel Catfish 6 1

Saugeye 0 1

Common Whitefish 1 0

Stonecat 2 1

Yellow Perch 0 1
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 7

Figure 5. Mean total lengths of fish collected at Leland Olds Station

0

2

4

6

8

10

12

14

June 16, 2006June 29, 2006

July 13, 2006July 27, 2006

Aug 10, 2006Aug 24, 2006

Sept 7, 2006

Sept 21, 2006

Oct 10, 2006Oct 19, 2006

Nov 2, 2006

Nov 16, 2006Nov 30, 2006

Dec 14, 2006Dec 28, 2006

Jan 11, 2006Jan 25, 2006

Feb 8, 2006

Feb 22, 2006

Mar 8, 2006

Mar 22, 2006

Apr 5, 2006

Apr 19, 2006

May 3, 2006

May 17, 2006May 31, 2006

June 14, 2006June 28, 2006

Collection Date

T

otal L

e

n

gth (c

m)

AM - Smelt

PM - Smelt

AM - Emrld Shiner

PM - Emrld Shiner

AM - Gizzard Shad

PM - Gizzard Shad

Figure 6. Mean total lengths of fish collected at Stanton Station

0

2

4

6

8

10

12

14

June 16, 2006June 29, 2006

July 13, 2006July 27, 2006

Aug 10, 2006Aug 24, 2006

Sept 7, 2006

Sept 21, 2006

Oct 10, 2006Oct 19, 2006

Nov 2, 2006

Nov 16, 2006Nov 30, 2006

Dec 14, 2006Dec 28, 2006

Jan 11, 2006Jan 25, 2006

Feb 8, 2006

Feb 22, 2006

Mar 8, 2006

Mar 22, 2006

Apr 5, 2006

Apr 21, 2006

May 3, 2006

May 17, 2006May 31, 2006

June 14, 2006June 28, 2006

Collection Date

T

otal L

e

n

gth (c

m)

AM - Smelt

PM - Smelt

AM - Emrld Shiner

PM - Emrld Shiner

AM - Gizzard Shad

PM - Gizzard Shad
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 8

Figure 7. Mean weight of fish collected at Leland Olds Station

0

2

4

6

8

10

12

June 16, 2006June 29, 2006

July 13, 2006July 27, 2006

Aug 10, 2006Aug 24, 2006

Sept 7, 2006

Sept 21, 2006

Oct 10, 2006Oct 19, 2006

Nov 2, 2006

Nov 16, 2006Nov 30, 2006

Dec 14, 2006Dec 28, 2006

Jan 11, 2006Jan 25, 2006

Feb 8, 2006

Feb 22, 2006

Mar 8, 2006

Mar 22, 2006

Apr 5, 2006

Apr 19, 2006

May 3, 2006

May 17, 2006May 31, 2006

June 14, 2006June 28, 2006

Collection Date

W

eig

ht (g)

AM - Smelt

PM - Smelt

AM - Emrld Shiner

PM - Emrld Shiner

AM - Gizzard Shad

PM - Gizzard Shad

Figure 8. Mean weight of fish collected at Stanton Station

0

2

4

6

8

10

12

14

June 16, 2006June 29, 2006

July 13, 2006July 27, 2006

Aug 10, 2006Aug 24, 2006

Sept 7, 2006

Sept 21, 2006

Oct 10, 2006Oct 19, 2006

Nov 2, 2006

Nov 16, 2006Nov 30, 2006

Dec 14, 2006Dec 28, 2006

Jan 11, 2006Jan 25, 2006

Feb 8, 2006

Feb 22, 2006

Mar 8, 2006

Mar 22, 2006

Apr 5, 2006

Apr 21, 2006

May 3, 2006

May 17, 2006May 31, 2006

June 14, 2006June 28, 2006

Collection Date

W

eig

ht (g)

AM - Smelt

PM - Smelt

AM - Emrld Shiner

PM - Emrld Shiner

AM - Gizzard Shad

PM - Gizzard Shad
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 9

In the second quarter of 2006 no large fish were collected. The heaviest and longest fish 

collected in the second quarter was the single yellow perch found at Stanton in the morning 

sample of April 5. It weighed 21 g and was 12.5 cm in length (total). The largest fish 

collected during the entire study period was a channel catfish (Ictalurus punctatus, 761 g and 

42 cm in total length), found in the collection basket at Leland Olds in the morning of 

February 22. 

Minimum and maximum weights of smelt, emerald shiners and gizzard shad were calculated 

and reviewed (Tables 2-5). The higher lengths and weights of smelt collected at Leland Olds

and, to a lesser degree, Stanton in late 2005 and early 2006 are reflected in the minimum 

and maximum weights for that species shown in Tables 2-5 . Maximum weights of smelt, in 

particular, were much higher in the morning samples collected from late December 2005 

through early February 2006. The largest specimens reached nearly 20 g. Minimum weights 

of smelt also tended to be higher during that same period, compared to earlier in 2005. The 

few smelt collected at Stanton at the end of March and the second quarter of 2006 were 

relatively small and comparable to fish collected during the summer of 2005. 

Because gizzard shad were not found in collection baskets after mid-December 2005, weight 

and length data for 2006 are unavailable. The minimum and maximum weights of the 

emerald shiners which reappeared in December 2005 and dominated samples in the second 

quarter of 2006, do not suggest any demonstrable shift in the sample population size or age. 
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 10

Table 2. Changes in minimum and maximum weights of the three most common 

species found at the Basin Leland Olds CWIS during the morning collection events

Collection 

Date

Rainbow Smelt Emerald Shiner Gizzard Shad

Minimum Maximum Minimum Maximum Minimum Maximum

Leland Olds AM Sample Collection

June 16, 05 2.5 7.1 7.0 7.5

June 29, 05 4.5 5.0 4.5 4.5

July 13, 05

July 27, 05 4.0 4.0

Aug 10, 05 1.5 1.5

Aug 24, 05

Sept 7, 05 1.5 3.5

Sept 21, 05 1.5 1.5 2.5 3.5

Oct 10, 05 0.5 5.0 4.0 6.0

Oct 19, 05 1.0 1.0

Nov 2, 05 2.0 2.0 2.0 2.0

Nov 16, 05 3.0 4.5 4.5 9.0

Nov 30, 05 2.0 5.0 2.0 14.0

Dec 14, 05 1.0 2.5 1.5 2.5

Dec 28, 05 7.0 17.0

Jan 11, 06 2.0 16.0 3.0 3.0

Jan 25, 06 3.0 19.0

Feb 8, 06 5.0 11.0

Feb 22, 06 2.0 2.0

Mar 8, 06

Mar 22, 06 2.5 4.5

Apr 5, 06 2.5 6.0

Apr 19, 06 3.0 3.0

May 3, 06 2.5 2.5

May 17, 06

May 31, 06 3.5 3.5

June 14, 06 2.5 2.5

June 28, 06

Note: Weight is in grams
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 11

Table 3. Changes in minimum and maximum weights of the three most common 

species found at the Basin Leland Olds CWIS during the evening collection events

Collection 

Date

Rainbow Smelt Emerald Shiner Gizzard Shad

Minimum Maximum Minimum Maximum Minimum Maximum

Leland Olds PM Sample Collection

June 16, 05 3.0 3.0 4.0 5.0

June 29, 05 1.5 3.0 1.0 6.5

July 13, 05 3.0 3.0

July 27, 05

Aug 10, 05

Aug 24, 05 1.5 1.5 2.0 3.0

Sept 7, 05 3.0 6.0 1.5 2.5

Sept 21, 05 9.0 9.0 1.0 8.5

Oct 10, 05 2.5 8.5 3.5 5.0

Oct 19, 05 2.5 2.5 3.0 3.0

Nov 2, 05 0.5 3.0 2.5 6.0

Nov 16, 05 1.0 10.0 4.0 5.0

Nov 30, 05 1.5 1.5 3.0 12.0

Dec 14, 05 2.5 2.5 3.0 8.0

Dec 28, 05 3.0 5.0 2.0 2.0

Jan 11, 06 3.0 16.0

Jan 25, 06 1.0 12.0 2.0 2.0

Feb 8, 06

Feb 22, 06 9.0 9.0

Mar 8, 06 3.0 3.0

Mar 22, 06 5.5 5.5

Apr 5, 06

Apr 19, 06 1.0 2.5

May 3, 06 0.5 0.5

May 17, 06

May 31, 06 0.5 3.0

June 14, 06 2.0 2.0

June 28, 06 3.0 3.0

Note: Weight is in grams
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 12

Table 4. Changes in minimum and maximum weights of the three most common 

species collected at the GRE Stanton CWIS during the morning collection events

Collection 

Date

Rainbow Smelt Emerald Shiner Gizzard Shad

Minimum Maximum Minimum Maximum Minimum Maximum

Stanton AM Sample Collection

June 16, 05 2.0 5.5 2.5 5.0

June 29, 05 3.0 4.5

July 13, 05

July 27, 05 3.0 3.0

Aug 10, 05 4.0 4.0

Aug 24, 05 2.0 2.0

Sept 7, 05 0.5 5.0 4.0 4.0

Sept 21, 05 0.5 10.5

Oct 10, 05 0.5 7.5 4.5 4.5

Oct 19, 05 0.5 6.5 4.5 4.5

Nov 2, 05 1.0 3.5

Nov 16, 05 1.5 4.5 4.0 8.0

Nov 30, 05 2.0 10.0 3.0 13.0

Dec 14, 05 2.0 10.0 0.5 2.5

Dec 28, 05 1.0 6.0

Jan 11, 06 1.0 16.0 1.5 3.0

Jan 25, 06 1.0 2.0 0.5 3.0

Feb 8, 06 3.0 3.0

Feb 22, 06

Mar 8, 06

Mar 22, 06 0.5 0.5

Apr 5, 06 1.0 1.5 1.0 4.5

Apr 21, 06 0.5 4.0

May 3, 06 2.0 3.0 1.0 1.5

May 17, 06 1.0 3.0

May 31, 06 1.0 1.0

June 14, 06

June 28, 06 4.0 4.0

Note: Weight is in grams
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 13

Table 5. Changes in minimum and maximum weights of the three most common 

species collected at the GRE Stanton CWIS during the evening collection events

Collection 

Date

Rainbow Smelt Emerald Shiner Gizzard Shad

Minimum Maximum Minimum Maximum Minimum Maximum

Stanton PM Sample Collection

June 16, 05 1.0 1.0 1.0 3.0

June 29, 05 1.5 7.5 0.5 2.5

July 13, 05 4.5 4.5

July 27, 05

Aug 10, 05 2.5 6.0

Aug 24, 05

Sept 7, 05 0.5 8.5 2.5 2.5

Sept 21, 05 1.0 9.0 2.0 3.0

Oct 10, 05 1.5 8.0

Oct 19, 05 1.0 1.5 5.0 8.5

Nov 2, 05 0.5 2.5

Nov 16, 05 1.0 2.0 4.0 4.5

Nov 30, 05 3.0 9.0 3.0 15.0

Dec 14, 05 9.0 19.5 2.0 2.5

Dec 28, 05 0.5 2.0

Jan 11, 06 1.5 7.0

Jan 25, 06 1.0 3.0 1.0 2.0

Feb 8, 06

Feb 22, 06

Mar 8, 06

Mar 22, 06 4.0 4.0

Apr 5, 06 2.0 3.5

Apr 21, 06 1.5 3.5

May 3, 06 1.5 1.5 0.4 2.0

May 17, 06 1.0 6.0 1.5 7.0

May 31, 06

June 14, 06

June 28, 06

Note: Weight is in grams

Most fish recovered from the collection baskets were classified as dead, meaning that at the 

time of collection, there was no visible movement of the body, including gill covers, fins or 

tail. This does not necessarily mean that a fish was dead when impinged. In many cases the 

fish appear to be in good shape when collected which means they may have been alive 
Fish Impingement Investigation 

Interim Data Summary on Fish Collection, June 2005 – June 2006 Page 14

when impinged and subsequently died on the screens. At other times fish are decayed, 

which suggests death prior to impingement.

Summary

 A total of 19 fish species were identified since the beginning of the study in the 

combined Leland Olds and Stanton samples,

 No fish have been collected at the Minnkota M.R. Young CWIS,

 While very low numbers of fish were collected in the first quarter of 2006, the number 

of collected fish increased in the second quarter

 In the second quarter of 2006, through mid-May, the collection basket at Stanton 

generally yielded more fish; in late May and June Leland Olds typically yielded more 

fish, although numbers from both facilities were low,

 Gizzard shad were not collected in 2006,

 Rainbow smelt were collected in low numbers only at Stanton,

 Emerald shiners were the most common species in the second quarter of 2006, and

 Fathead minnows, though still present in low numbers, were more common in the 

second quarter of 2006.