Chapter 4 AN ANALYSIS OF STRAWBERRY CREEK'S WATER QUALITY. Lori A. Cheung

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1 Chapte 4 AN ANALYSS OF STRAWBERRY CREEK'S WATER QUALTY Loi A. Cheung ntoduction "f thee is magic on this planet, it is in wate" (Mille, 982, p. 357). ndeed, the quality of life that we enjoy depends to a geat extent upon the quality of ou wate. Stawbey Ceek, flowing though the beautiful U.C. Bekeley campus, seems to elax the huied atmosphee of the academic institution. The ceek oiginates in the Bekeley Hills and flows westwad until it eventually eaches San Fancisco Bay. Histoically, Stawbey Ceek was once "choked with fish" and povided an impotant esouce fo Bekeley (Stine, 984, pes. comm.). Today, howeve, the divesity and abundance of all oganisms ae geatly deceased. One eason fo the decline in numbes of species and populations is that the ceek seves as a catchment fo uban unoff, which caies pollutants along with it. This poject focuses on the wate quality of Stawbey Ceek on the U.C. Bekeley campus and at its outflow into San Fancisco Bay via the Univesity Avenue stom dain (Figue ). The eseach investi gated the diffeences in the levels of total colifom counts, dissolved oxygen, and ph at thee study sites on campus and at one site nea the stom dain. Wate samples wee collected duing and afte ainy peiods to detemine if wate quality is affected by the inceased unoff. The esults of this poject wee compaed with those of past studies to see if changes in wate quality ae occuing. Backgound Colifoms ae a goup of micooganisms that seve as indicatos of micobial diseases tansmitted via wate. The moe commonly known diseases include typhoid feve, cholea, salmonellosis, and infectious hepatitis (Bock and Smith, 984). None of the micooganisms causing these diseases ae easily isolated fom wate no eadily enumeated. Because of the difficulty in detemining the pesence of these mico oganisms diectly, indicato micooganisms ae used. Thei pesence can be easily detemined, thei density can be estimated, and thei occuence is indicative of human o animal wastes (APHA, 976). The colifom goup ae suitable indicatos because they ae common inhabitants of the intestinal tact of both humans and othe wam-blooded animals and ae geneally pesent in lage numbes. t is theefo-e likely that if colifoms ae found in wate, the wate has eceived fecal contamination ano may be unsafe fo potable o eceational use. The Regional Wate Quality Contol Soad (RWQCB) standad fo wate contact spots (REC- wate uses) is 240 oganisms pe 00 ml fo total colifoms (RWQCB, 982)

2 «CREEKS ABOVE GROUND a a. CREEKS UNDERGROUND San Fancisco Bay 2000 Figue. Map of the ceeks of Bekeley shpwing the study sites located on the Univesity of Califonia campus and at the Univesity Avenue stom dain. Base Map: Maste Plan Revision Committee, Bekeley Planning Dept., 975

3 The thee majo causes of bacteial contamination of Stawbey Ceek ae: () the deposition of animal fecal mateial in aeas subject to unoff, (2) coss connections with sanitay sewes, and (3) malfunctioning septic tanks (ABAG, 978). Dissolved oxygen (DO) is anothe impotant wate quality facto to assess. DO, a fundamental e quiement fo plant and animal populations in a body of wate, is dependent upon the physical, chemical, and biochemical activities pevailing in that wate (Rand and Petocelli, 985). The pimay cause of wate deoxygenation is the pesence of oxygen-demanding wastes, such as domestic sewage, animal wastes, and decaying plant matte. These wastes do not use DO diectly, but the bacteia and othe micoogan isms that decompose them do (Mille, 982). Consequently, if wate systems ae oveloaded with wastes, the esulting population explosion of decomposes will consume much of the DO supply, with the esult that fish and othe aquatic life cannot suvive. The DO standad set by the RWQCB fo wates inland i i fom the Golden Gate Bidge is 5 ppm (RWQCB, 982). The ph of natual wate is an impotant index of acidity o alkalinity and is the esult of the acidic/basic inteaction of a numbe of mineal and oganic components of wate. n pue of slightly polluted wate, the values of ph ae detemined mainly by the coelation between the concentations of fee cabon dioxide, bicabonate, and cabonate ions (HD-WHO, 978). This coelation, in tun, depends on the intensity of photosynthesis and the biochemical oxidation of oganic substances, as well as on the chemical convesions of some mineal substances. The RWQCB standad fo ph is that it should not be less than 6.5 no geate than 8.5 (RWQCB, 982). The eason fo this objective is that most aquatic oganisms live in an aquatic envionment within this ange (Rand and Petocelli, 985). The ph of a solution is expessed as the logaithm of the ecipocal of the hydogen ion activity in moles pe lite. - The ph scale extends fom 0, vey acidic, to 4, vey alkaline, with 7 coesponding to exact neutality at 25 C (APHA, 976). Past Studies Many of the past wate quality tests pefomed on Stawbey Ceek focused on the micobiological aspect, namely, colifom levels. Pesently, few data ae available on dissolved oxygen and ph values at these locations. Colifom tests at the Univesity Avenue stom dain wee conducted by the East Bay Municipal Utility f Distict (EBMUD) (Shape, 977) and Reed (985). Colifom studies on the U.C. Bekeley campus wee done by the U.C. 3ekeley Office of Envionmental Health and Safety ;Heea, 977), the City of Bekeley (Gebe, 978), and Lee (982). The only DO and ph data available fo Stawbey Ceek ae those of Fazie (983). Methodology Thee study sites ae located on the U.C. Bekeley campus and one at the Univesity Avenue stom dain (Figue ). The map of the campus shows study sites A, B, and C in geate detail (Figue 2).

4 ' J mk Figue 2. Map of the U.C. Bekeley campus showing study sites A, B, and C. Base Map: Publications Office, U.C. Bekeley, 986. Site A is located in font of the amphitheate, 0 m east of the Sathe Gate bidge on the south fok of Stawbey Ceek. Site B is 5 mdownsteam fom the bidge located between Giannini Hall and the Life Sciences Building on the noth fok. Site C is on the southwest cone of the Eucalyptus Gove, 5 mbelow the mege of the noth and south foks of the ceek. Site Dis 0 m southeast of the Uni vesity Avenue stom dain in the shelteed inlet. Wate samples wee collected in 70 ml steile plastic bottles which wee insed with the sample two times befoe the wate was collected. The samples fom sites A, B, and C wee taken in the middle of the ceek in flowing wate. The samples fom site Dwee taken 0.5 maway fom the wate's edge in moving wate. The samples wee collected by immesing the bottles 3 cm below the wate's suface and allowing them to fill. The wate was bought back to a U.C. Bekeley Depatment of Public Health laboatoy fo colifom analysis. The tests wee begun within 2 hous of collection. af

5 DO and ph tests wee pefomed at the study aeas. A Leeds and Nothup Potable Dissolved Oxygen Mete Model Numbe 7932 was used to detemine the DO of the wate. A Leeds and Nothup Potable ph Mete was used to detemine ph. and accuate eading. The pobe of each mete was placed diectly into the ceek fo a diect At each site, thee eadings wee taken and the aveage ecoded. Wate quality tests wee conducted on Octobe 23, Novembe, and Novembe 22, 985 duing a dy peiod and on Febuay 20, 986 afte a ainstom. ADO test was not conducted on Febuay 20 due to equipment malfunctions. The Febuay 20 tests wee not made duing the fist stom of the yea. Duing 986 the total amount of pecipitation pio to the wet weathe sample was 6.28 inches (U.S. Weathe Bueau, U.C. Bekeley Station). At site D the wate is subject to tidal influence. Octobe 23 and Novembe 22 occued duing a low tide. Tests conducted duing the late aftenoon of Tests wee pefomed duing high tide on the late aftenoon of Novembe and the late moning of Febuay 20. The Mcst Pobable Numbe (MPN) method was used to examine the wate fo colifom counts. Thee ae thee pats to this technique: the pesumptive test, the confimed test, and the completed test. Usually, only the fist two tests ae caied out, the pocedue followed in this poject. Fo the pesumptive test, ten-fold dilutions of the wate sample wee planted in lauyl typtose fementation tubes and in cubated fo 24-2 hous at 35 C C. f no gas was poduced o if gas poduction was doubtful, the tubes wee incubated anothe 24 hous. Fo the confimed test, a small potion of the media fom the positive pesumptive tubes was inoculated in billiant geen bile both and incubated fo 48-3 hous at 35 C C. f gas appeaed, the colifom goup was confimed. The MPN of colifoms is calculated by efeing the combination of positive tubes and the dilutions used to tables in Standad Methods fo Examination of Wate and Wastewate (APHA, 976). Results Not all of the wate quality paametes tested in Stawbey Ceek met RWQCB standads. Colifom levels wee exceedingly high and violated the standad; howeve, DO and ph wee within standads at the time of testing. The data collected fom the colifom tests (Table ) show that the colifom levels wee all above the RWQCB standad of 240 MPN/00 ml. Sites A, B, and Chad simila colifom levels thoughout the study. Most MPN values wee eithe of the same magnitude o diffeed by 0 times. The colifom densities at the campus sites anged fom.09 x 04 to 0 x 04 MPN/00 ml. The Sathe Gate bidge site (site A) had the least contamination with a mean density of.5 x 04 MPN/00 ml. The stom dain site (site D) nad the geatest mean density, 600 x 0 MPN/00 ml. The dissolved oxygen data (Table 2) indicate that all of the sites met the RWQC3 standad of 5 ppm. Sites A, B, and C had elatively high DO levels, anging fom 8.5 to 0.0 ppm. The highest DO concenta tions wee at site A on each testing date. Site Ahad a mean DO level of 9.5 ppm. Both sites B and C had a mean DO level of 9.2 ppm. The lowest DO concentations wee at site Dwith a mean DO level of 7.4 ppm.

6 Total Coli foms (MPN x 04 goo ml) Octobe 23 Novembe Novembe 22 Febuay 20 mean (0.28 ins) (0.00 ins) (0.0? ins) (2.00 ins) Site A Site Site C Site D Table. Total colifom levels'at the study sites. The amount of pecipitation 48 hous pio to the testing date is in paenthesis. 0' = 0,000. Dissolved Oxygen (ppm) Octobe 23 Novembe Novembe 22 mean (0.28 ins) (0.00 ins) (0 02 ins) Site A Site B Site C Site D Table 2. Dissolved oxygen levels at the study sites. The amount of pecipitation 48 hous pio to the testing date is in paenthesis. The ph values anged fom 7.2 to 8.2 (Table 3) and wee within the RWQCB standad ange of 6.5 to 8.5. The ph at site Dwas consistently lowe than that at the othe thee sites, except on Novembe 22 wnen the ph at site D was the highest of the fou sites.

7 Pi " Octobe 23 Novembe Novembe 22 Febuay 20 (0.28 ins) (0.00 ins) (0.02 ins) (2.00 ins) Site A Site B Site C Site D Table 3. ph levels at the study sites. The amount of pecipitation 48 hous pio to the testing date is in paenthesis. f ~ Discussion Geneally somewhat lowe wate quality was found in the pesent study than in past studies pefomed on Stawbey Ceek. Compaed with pevious studies, this study showed an incease in the density of colifoms, a lowe dissolved oxygen level, and a elatively constant ph. At most sites the ainfall did not have much of an effect on the densities of colifoms. The wet weathe samples taken in this study vaied only by 0-fold fom the dy weathe samples. expected highe colifom densities because of the inceased unoff which pobably caied moe pollutants. The most likely eason why thee wasn't a maked effect was because the wate quality was not assessed afte the fist big ainstom, which could have flushed the bulk of the pollutants into the Bay. This hypothe sis pobably applies to othe past studies which have found lowe colifom densities afte ainstoms (Heea, 977). Site C had a 00-fold incease in colifoms afte the ainfall; the likely cause was that unteated wate was oveflowing fom a manhole cove located upsteam fom the site in the Eucalyptus Gove on the day of testing. The high colifom levels (Table ) indicate that the ceek is bacteiologically contaminated and unfit fo human contact. The data show that noth and south foks of Stawbey Ceek ae about equally contaminated. The eason why the campus sites had simila MPNs thoughout the study may be due to thei close poximity to each othe. The low density of colifoms at site Aon Novembe 22 was unexpected because the othe campus sites had 00 times geate MPNs on the same day. Pehaps thee was an inceased flow of clean wate into site Awhich diluted the numbe of colifoms that day. Dischage at the Uni vesity Avenue stom dain (site D) was exceedingly contaminated. On Octobe 23 and Novembe it had 00,000 times moe colifoms pe 00 ml than the RWQCB standad. Colifom densities at site Dae

8 expected to be highe than at the campus sites because wate collects pollutants, such as fecal matte, on the way downsteam and with inceased unoff. Side D is also a location whee unteated wastes fom the local steets dain into the Bay. Past studies also demonstated exteme contamination at the stom dain but with elatively lowe colifom densities than found in the pesent study (Table 4). On the basis of EBMUD's 976 data, it is impossible to be cetain that densities ae inceasing ove time because the data ae not sufficiently detailed. EBMUD found that colifoms geneally exceeded 24 x 04 MPN/00 ml but did not specify vihat Total Colifoms (MPN x 04/00 ml_) Month 976a 977a 985b Januay Febuay 2.4 Mach 24 + Api 2.4 May 24 + June July August 24 + Septembe 24 + Octobe 2.4 Novembe Table 4. Results of colifom tests pefomed at the Univesity Avenue stom dain in past studies. Souce: a) Shape, 977; b) Reed, 986. the actual densities wee. Othe data, howeve, indicate that colifom densities ae indeed inceasing ove time. EBMUD's 977 study found MPNs,000 times less than the densities obtained in the pesent study (Shape, 977). n 985, Reed found a colifom density 00 times less than the densities shown in the pesent study (Reed, 985). Pehaps the incease in bacteial contamination is due to an incease in the numbe of pets oaming the steets o pehaps the sewe lines ae deteioating quickly, leaving unteated sewage to flow feely into the stom dain. EBMUD has identified the gadual deteioation of sewe systems, accompanied by a chonic unde-investment in sewe system maintenance and impovements, as one of the East Bay's geatest wate quality poblems (EBMUD, 983). Past colifom studies pefomed on the U.C. Bekeley campus do not give a clea pictue of geneal tends in bacteial contamination. The colifom levels found in the pesent study ae eithe compaable

9 to those of past studies o show an incease in the density of colifoms (Table 5). The MPNs found in the pesent study ae of the same magnitude as the MPNs of Gebe (977). Howeve, both Heea (977) and Lee's (982) data show colifom densities that ae less than the levels found in the pesent study, suggesting that bacteial contamination is wosening ove time. Total Colifoms (MPN x 04/00 ml_) " Location 7//76 2/4/76 8/24/77 8/25/77 9/2/77 4/9/82 Stawbey Ceek nea Oxfod St. 2.4 South fok of - Stawbey Ceek Bidge acoss fom - Giannini Hallc - Table 5. Results of colifom tests pefomed on the U.C. Bekeley campus in oast studies. Souce: a) Gebe, 977; b) Heea, 977; c) Lee, The mean dissolved oxygen values in the pesent study ae lowe than those of Fazie (983). Fazie found DO levels nea o at satuation level: DO eadings anged fom 9.8 ppm to.4 ppm on campus, wheeas levels at the stom dain anged fom 8.8 ppm to 0.5 ppm. Fazie (983) attibutes the lowe DO values at the stom dain to the lowe DO level of the Bay. One eason why DO concentations may be lowe in the pesent study than in Fazie's is that thee may be moe oxygen-demanding substances in Stawbey Ceek today than in 983. Site Dpobably has the most oxygen-demanding wastes flowing into it fom the high amount of uban unoff that it eceives. The ph has emained elatively stable ove time and did not change significantly afte the wet weathe on Febuay 20. The ph levels found in the pesent study and in Fazie's study (983) both indicate that the wate is nealy neutal to slightly alkaline. Fazie's ph levels anged fom 7.6 to 8.4 in Stawbey Ceek, slightly lowe than levels in the pesent study. Conclusion Accoding to the esults obtained in this epot, the geatest dange in Stawbey Ceek's wate quality is the high colifom levels. The exceedingly high levels, especially at the Univesity Avenue stom dain, pose a potential health hazad. Since most of the wate that flows though the ceek even tually eaches San Fancisco Bay, any pollution pesent in Stawbey Ceek also affects the wate quality of the Bay.

10 Recent poposals fo a shoeline pak at the Bekeley watefont include an option to open Staw bey Ceek up and to channel it acoss the Bickyad aea (Siefken, 986, pes. comm.). Stawbey Ceek would geatly enhance the atmosphee of the pak, allowing visitos the oppotunity to enjoy the beauty and sound of the flowing wate. The ceek and the ipaian vegetation along it would pobably attact bids and othe animals to the site which othewise would not be pesent. A management plan to decease the high levels of colifoms should be implemented as soon as possible to decease the health hazad involved. The Association of Bay Aea Govenments (ABAG) has ecommended 7 majo types of suface unoff contol measues including: teatment and stoage of unoff, impove ment of steet sweeping, and management of sewe lines and septic tanks (ABAG, 975). All eight Bay Aea counties in the ABAG study epoted a bacteial contamination poblem. Thus, the poblem is wide spead and should be dealt with in the nea futue. "! The San Fancisco Bay ecosystem is a unique place thee ae biological, physical, and social aspects to this ecosystem that do not occu anywhee else. Wate quality must be managed effectively so that futue geneations can enjoy the Bay. REFERENCES CTED Ameican Public Health Association (APHA), 975. Standad Methods fo the Examination of Wate and Wastewate, 4th edition, Ameican Public Health Association, Washington, D.C., 93pp. Association of Bay Aea Govenments (ABAG), 975. San Fancisco Bay Aea Envionmental Management Plan, Volume : Policies, Actions, and Explanatoy Mateial; Association of Bay Aea Govenments, Oakland, Califonia, n.p. Bock, Thomas and David Smith, 984. Biology of Micooganisms; New Jesey: Pentice-Hall, nc., 847pp. ' " East 8ay Municipal Utility Distict (EBMUD), 983. East Bay Sewes: Past, Pesent, and Futue; East Bay Municipal Utility Distict, Oakland, Califonia, pp. Fazie, Thomas, C, 983. Wate quality in Stawbey Ceek. hi_ Bekeley Wate: ssues and Resouces, D. Sloan and S. Stine, eds., U.C. Bekeley Envionmental Sciences Senio Semina epot, Bekeley, Califonia, pp Gebe, Matin J., 978. Unpublished data, Maina and Stawbey Ceek Wate Quality Suvey, fo the City of Bekeley, Envionmental Health Section, 9pp. Heea, Josefina R., 977. Unpublished data on Stawbey Ceek, fo the Univesity of Califonia at Bekeley, Office of Envionmental Health and Safety, n.p. HD-WHO Woking Goup on the Quality of Wate (HD-WHO), 978. Wate Quality Suveys: A Guide fo the Collection and ntepetation of Wate Quality Data; Doset: Sydenhams Pinte, 350pp. Lee, bessie, 982. Wate quality of ceeks and stom dains. n The East Bay Shoeline, D. Sloan, ed., U.C. Bekeley Envionmental Sciences Senio Semina epot, Bekeley, Califonia, pp Mille, G.T., 932. Living in the Envionment; Belmont: Wadswoth Publishing Company, 500pp. Rand, Gay and Sam Petocelli, 985. Fundamental of Aquatic Toxicology: Methods and Application; New Yok: Hemisphee Publishing Cop., 528pp. Reed, Chales, 985. The effect of suface unoff on eceation-use wates, iji Open Space and Develop ment: Focus on the East Bay, D. Sloan, ed., U.C. Bekeley Envionmental Sciences Senio Semina epot, Bekeley, Califonia, pp !

11 Regional WAte Quality Contol Boad (RWQCB), 982. Wate Quality Contol Plan, San Fancisco Bay Basin, Oakland, Califonia: Regional Wate Quality Contol Boad, San Fancisco Bay Region, Oakland, Califonia, 82pp. Shape, Cliffod, 977. An analysis of the factos affecting the possible establishment of a commecial shellfish opeation in San Fancisco Bay along the Bekeley shoeline, epot fo the Califonia Depatment of Health Sevices (Sanitay Engineeing), 52pp. Siefken, Bob, Poject Manage, Lay Seman Associates. Pesonal communication, 986. Stine, Scott, Lectue, Division of Special Pogams, Envionmental Sciences, U.C. Pesonal communication, 984. Bekeley. U.S. Weathe Bueau, U.C. Bekeley Station, 986.