Water Quality Division

Blue Thumb Program

Data Interpretation  

Fred Creek: Evanston 

NE NW SE
Section 8-18N-13E
Tulsa County
Lat N 36 3’ 8”
Long W 95 56’ 48”
WBID#: OK 120420-01-0060G

The headwaters of Fred Creek begin at South 71st Street and Yale Avenue in Tulsa. The creek runs southwest through residential neighborhoods to the monitoring site at Evanston and continues through the Oral Roberts University Campus, through a light commercial area, then empties into the Arkansas River. The monitoring site is at the bridge where Evanston crosses the creek in a pooled area just east of the bridge itself. As this area has built up, portions of Fred Creek have been channelized.

The habitat at the creek has been assessed three times: 1993, 1996 and 1999 and is scheduled to be assessed again in the summer of 2007. The habitat has been better than the habitat in the average of high quality “reference” streams in the Central Irregular Plains ecoregion. Instream cover for fish is great, there is good canopy shade and the banks have good vegetative cover and are very stable. The creek has very low flow and the channel is very straight. There is a mixture of deep and shallow pools. Even though the habitat is better than reference conditions, according to the previous accumulated data the condition has been declining in the past several years. The habitat score has dropped 19 points from 110.3 in 1993 to 91.2 in 1999. It is still better than the reference average of 86.8.

There have been three collections of fish; 1993, 1996, and 1999. Another collection is scheduled for the summer of 2007. All three fish collections have been very poor. In comparison to reference averages, the number of species collected is extremely low as is the total number of fish collected. The fish that were collected were tolerant species. There were no intolerant species found. In fact, on 7/23/1999 only 14 fish were collected from the entire 400 m reach of stream and they were all the same tolerant species, the green sunfish. In comparison, you would expect a creek in this ecoregion to have 22 species of fish, three intolerant species, and six sunfish species alone.

Macroinvertebrate collections took place in the rocky riffles of Fred Creek. There were 11 summer collections beginning in 1993, and 5 winter collections since 2001. For the last five years, Fred Creek has about half the number of total species expected under reference conditions. Most significant was the absence of Ephemeroptera, Plecoptera and Tricoptera (EPT) species. With few exceptions, these insects are more sensitive to pollution than any other groups. As a stream deteriorates in quality, members of this group are the first to disappear. The diversity was also low, especially in the summer collections. The summer collections are about 30% as good as reference conditions; winter collections are about 40% of reference conditions.

Water chemistry shows that Fred Creek has had a continuing problem with low dissolved oxygen, especially during the hottest summer months. There was a period from July 2002 through January 2003 when it was below 5 mg/L oxygen the entire time and the oxygen saturation dropped to 14% on 11/21/2002. Also during the summer months the orthophosphate phosphorus is often near or above 0.1 mg/L phosphorus. Perhaps the nutrients being applied to neighborhood lawns are making their way into Fred Creek and causing algal blooms with the consequence that the oxygen levels are low in the morning before the sun has been up long.

Fred Creek drains an urban watershed with many impervious surfaces. As development has increased, portions of the creek have been channelized. The reach of stream monitored still has very good habitat for fish and benthic macroinvertebrates. Water chemistry shows problems with excess nutrients and the amount of oxygen in the water. The fish and macroinvertebrate collections show few species and individuals present; about 30% of what would be expected in high quality streams in the Central Irregular Plains ecoregion. Fred Creek at Evanston is not a healthy stream.

Fred Creek: Evanston
NE NW SE
Section 8-18N-13E
Tulsa County
N 36° 3’ 8”
W 95° 56’ 48”
WBID#: OK 120420-01-0060G

Blue Thumb Volunteer Monitoring Data Review of data collected between October 1994 and August 2007.

Fred Creek is located in the southern part of Tulsa County, which is located in the Central Irregular Plains ecoregion. The creek is an urban stream that has a watershed, or drainage area, of about four square miles that runs southwest from the intersection of 71st Street and Yale Avenue in Tulsa. The creek goes around the campus of Oral Roberts University (ORU), around Wal-Mart, near many housing sectors of the area, and under many streets. It runs throughout the city and empties into the Arkansas River. The monitoring site of the creek is on South Evanston Avenue.

From October of 1994 to August of 2007 there has been a trend of habitat loss in the creek. Much of the creek has been straightened and channelized. Where it is still natural, there is a lot of in-stream cover, places where fish and insects can hide beneath, behind, or within. The water depth of the pools varies highly, though there are not many riffles. The creek is quite shady and there are many different types of plants growing along the banks to help with the vegetation going into the creek. While the banks are stable, in many places they have been “stabilized” by the city. Because of all of the hard surfaces in the drainage area, Fred Creek floods during rain events and has very low flow the rest of the time. In the natural places, Fred Creek has habitat almost as good as the average high quality streams in the ecoregion.

From October of 1996 to August of 2007 fish were collected three times. If this creek were healthy there should have been about 550 individuals from 22 different species caught, but in all the times of fishing there have been less than 100 individuals (26, 14, and 95) from at most three of four different types caught; the Bluegill sunfish, Green sunfish, Largemouth bass and the Central stoneroller. All these fish are very tolerant to pollution and there were no sensitive species caught. This creek has the lowest ranking of E (from A to E), which means that there are few species and individuals present. The tolerant species are dominant and diseased fish are frequent.

From the winter of 1998 to 2007 bugs were collected from the riffles in the creek. In most of the collections the sensitive bug species in this creek were absent. From the summer of 1997 to 2007 bugs were also collected. While there were more sensitive bug species found than in the winter collections, there were between zero and two species found when you would expect to find seven in a healthy stream. The majority of the bug conditions ranked C, meaning that there were fewer species due the loss of most sensitive species.
The median oxygen saturation in Fred Creek was 71%, with highs occasionally over 100% and occasional lows of 25%. This is clearly less than optimal. The pH level of the creek is normal at 8. The soluble nitrogen level of the creek has a median value of 0.09 mg/L N, with occasional highs of 1.2 mg/L N. The orthophosphate of the creek has a median of 0.05 mg/L P and rarely reaches over 0.16 mg/L P. The median of the chloride level in the creek is 40 mg/L Cl. Bacteria tests show that the levels of E. coli are often high. This means that the creek is not suitable for swimming.

Fred Creek is located in southern Tulsa County. It has drainage of about 4 square miles and empties into the Arkansas River. Over the years it has had a trend in the loss of habitat. As an urban stream, its course doesn’t vary much and it rarely diverts from a straight line. While the remaining natural habitat is good, the fish collections in this creek are very poor. The fish condition is ranked at an E, which means that there are few species and individuals present. The tolerant species in this creek are dominant and diseased fish in this creek are frequent. In the winter and summer when bugs were collected there were many of the sensitive species missing. The majority of the bug conditions were ranked at a C; this means that there were fewer species due to the loss of the sensitive species. The chemistry of the creek is fair; nutrients are slightly higher than normal the dissolved oxygen is low. The fecal coliform, E. coli, in this creek is very high. This means that the creek is not suitable for swimming.

By Helen Talaese