Biological and Chemical Assessment of Water Quality in ... · Orlando and other inland areas. Soon, however, farmers began to clear the rich muck lands south of the lake to plant

Biological and Chemical Assessmentof Water Quality

inTributaries of Lake Jesup,Seminole County, Florida

Results of Sampling, July 1996 - September 1997

Surface Water Assessment and Monitoring SectionDivision of Water Facilities

Florida Department of Environmental ProtectionCentral District, Orlando

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Executive Summary

The water quality of eleven tributaries of Lake Jesup was examined from July 1996 throughSeptember 1997. Assessment tools included the following:

• biological assessment using the Stream Condition Index (SCI)

• water chemistry measurements of various nutrients

• determination of fecal coliform levels

• habitat assessment

• measurement of physicochemical parameters (DO, pH, temperature, and specific conductance)

The streams in the Winter Springs/Casselberry area (Soldier, Gee, Howell, and Bear Creeks) hadfair to good water quality. Nutrient levels were higher than the average for Florida streams, thoughnot excessive. Fecal coliform levels ranged from 170 to 620 colonies/100 mL, the highest being atSoldier Creek. All five sites (two sites at Howell Creek) rated good to very good on the StreamCondition Index (SCI). Results suggest that stormwater runoff and habitat alteration are the mainsources of degradation in these streams. Improvement or establishment of stormwater retentionsystems and possible re-establishment of riparian buffer zones are suggestions for improvement ofwater quality.

Four streams were monitored in Black Hammock near Oviedo: Sweetwater Creek, Black SweetwaterCreek, Salt Creek, and Shortcut Canal. Water quality was generally poor in these streams. In mostcases, nutrient levels were quite high. Fecal coliform readings ranged from 420 colonies/ 100mL atShortcut Canal to 1,300 at Black Sweetwater Creek. Biological assessment ranked the streams fromgood to poor; most had low numbers of macroinvertebrate taxa with few good water quality indicatorspecies present. Results suggest that the poor biological assessments are not due to the presenceof saline groundwater in this area. Shortcut Canal rated better than the other three streams on mostcounts. Black Sweetwater Creek was severely degraded. All of these streams are highly modified toserve as conduits for agriculturalrunoff. These box-cut ditches receive nutrient- and bacteria-enriched water from the numerous farmsin the area. We suggest that the Black Hammock area is a good candidate for an EcosystemManagement effort.

Elder Springs Run and the Airport Ditch were the two streams assessed in the Sanford area. Resultsfrom these two very different streams were fairly good. Nutrient levels were in the medium range.The Airport Ditch, which is made up almost completely of runoff from the Sanford Orlando RegionalAirport, had lower nutrient levels than Elder Springs Run. Fecals, though somewhat high at bothsites, did not exceed standards. Both sites received a good rating on the SCI, with macroinvertebratetaxa similar to those found in the Winter Springs area streams. Enhanced stormwater systems andagricultural best management practices would help to improve water quality in this area.

Overall, nutrients and fecal coliforms are fairly high in these streams. Most likely, these are results ofnonpoint source runoff from urban areas in Winter Springs, Casselberry, and Sanford, and fromagricultural activities in Oviedo. Without a doubt, the Black Hammock streams contain the highestconcentrations of nutrients of all the Lake Jesup tributaries sampled.

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PURPOSELake Jesup has been identified as one of themost hypereutrophic lakes in central Florida.Its often pea-green color is due to theproliferation of unicellular algae resultingprimarily from large amounts of nutrients. Fishkills, related to low oxygen conditions, arefrequent. As recently as May 1983, effluentsfrom several municipal wastewater treatmentplants directly or indirectly entered the lake viaits tributaries. Since then, all of these havediverted their effluent to the Iron Bridgeregional wastewater treatment plant. Morethan 20 years of such inputs, however, alongwith the constriction of the lake’s outlet to theSt. Johns River and runoff from the intensiveagricultural and cattle raising activities in thewatershed, have resulted in deposits (up to9.5 feet thick) of organic muck lining much ofthe lake bottom. Although the streams feedingthe lake no longer receive WWTP effluents,they have the potential to carry substantialloads of nonpoint source pollution from thesprawling urban development of the northernpart of Orange County and surrounding parts

of Seminole County into the lake. Thus, it isimportant to monitor these tributaries toassess the quality of water entering LakeJesup.Lake Jesup restoration efforts were begun bythe St. Johns River Water ManagementDistrict in 1994. Initial diagnostic activitiesincluded lake water quality monitoring andcirculation modeling to determine what effectsthe SR 46 constriction has had on theretention time of the lake. Since 1984,SJRWMD and other public agencies havepurchased some 6,700 acres of surroundingmarshlands for conservation, flood control,water quality improvement, and recreation. Adraft report of SJRWMD’s management planthus far has been prepared (Marzolf 1997). Itis hoped that the information contained in thisreport regarding water quality in Lake Jesup’stributaries will contribute to an understandingof the ecological health of the system as awhole, and help to identify land use patternswhich continue to contribute to thedegradation of Lake Jesup.

Map of Lake Jesup and vicinity, showing the eleven tributaries sampled.

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METHODSEleven sites on the ten largest streams andcanals flowing into Lake Jesup (see map)were monitored from July 9, 1996 throughSeptember 24, 1997. A number of smallertributaries also flow into the lake, but theywere not sampled in this study due to alack of flow during the sampling period orlimited access to the streams. Assessmentof the ecological condition of the streamswas based on four criteria:• macroinvertebrate community structure• water chemistry• physicochemical measurements• visual habitat assessmentsThe biological condition of the streams wasdetermined using the Stream ConditionIndex (SCI), an assessment tool developedby FDEP biologists in cooperation withTetra Tech, Inc. of Owings Mills, Md(Barbour et al. 1996). The SCI is anaggregation of seven different measures ofmacroinvert-ebrate community structure.Macroinverte-brates are small aquaticanimals without a backbone that spend allor part of their lives in specific streamhabitats. These include larval and adultinsects, crustaceans, molluscs, worms, andseveral other groups. They are used asindicators of ecosystem health due to theirrelative immobility within the stream, theirfairly long aquatic stages, and thesensitivity of many types to pollution,making them excellent integrators of waterquality changes over time. Used as anindicator of ecosystem health, the SCImeasures the degree of biologicalimpairment of a stream compared withsimilar reference (least impacted) streams.SCI methodology involves sampling theaquatic habitats present by collectingtwenty 0.5 m sweeps using a 0.3 m wide D-frame dipnet with 595 µm mesh. A randomsubsample of at least 100macroinvertebrates is then taken.

Core Metrics of the SCI.• Total number of macroinvertebrate taxa• Number of Ephemeroptera, Plecoptera, and

Trichoptera (EPT) taxa• Number of Chironomidae taxa• Percent dominant taxon• Percent Diptera• Florida Index• Percent filter feeders

Twelve different water chemistry analyseswere performed on samples taken at thesites. These included color, alkalinity, totalNH3, unionized NH3, total Kjeldahl nitrogen,nitrate/nitrite, total phosphorus, chlorides,sulfates, turbidity, and fecal coliformconcentration. Other physical parameters(dissolved oxygen, specific conductance,water temperature, and pH) were determin-ed using Hydrolab multi-meters. A visualdetermination of habitat quality was madeat each site. Samples were processed andanalyzed by FDEP’s Central Laboratory inTallahassee according to standardoperating procedures (FDEP 1994)

BASIN CHARACTERISTICSLake Jesup, a Surface Water Improvementand Management (SWIM) priority waterbody, has a surface area of some 10,000acres (16,000 counting wetlands andfloodplain). It is one of three large lakesassociated with the St. Johns River whichlie wholly or partially within SeminoleCounty. The others, Lakes Harney andMonroe, lie on the border between Semin-ole and Volusia Counties. Although LakeJesup proper is contained within SeminoleCounty, its approximately 150 mi2 water-shed includes parts of Orange, Volusia,and Seminole Counties. It has a meandepth of just over one meter, with depthsapproaching seven meters in a few spots. Itis fed by several natural streams, man-made canals, and broad wetland areas,plus discharge from Clifton Springs at thesouthern shore of the lake just east ofHowell Creek. Urban development spread-ing in a northeasterly direction from theOrlando area and southeastward fromSanford has largely surrounded thewestern part of the lake. Rapid growth isalso taking place in the vicinity of Oviedonear Lake Jesup’s southeastern shore. Theeastern part of the lake, where it meets theSt. Johns River, is less intenselydeveloped, with considerable amounts ofagriculture and relatively undeveloped landin the vicinity. The SR 46 causewayconstricts Lake Jesup’s outlet to the St.Johns, and a canal (Government Cut)diverts the flow of the river past the lakeoutlet.

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HISTORICAL BACKGROUND

To understand the anthropogenic impactscurrently affecting Lake Jesup, it is usefulto summarize the recent historicalbackground of settlement and land use inthe area. Agricultural activities and laterextensive urban development have bothleft their mark on the ecological health ofthe system.

The earliest post-Native American coloniz-ation of the Lake Jesup vicinity took placenear what is now the city of Oviedo. In themid-1800s, a settlement then referred to asSolary’s Wharf was established on thesouth shore of Lake Jesup. Initially, the fewresidents dealt in river traffic, transportinggoods by boat on the St. Johns, throughLake Jesup, and then overland to and fromOrlando and other inland areas. Soon,however, farmers began to clear the richmuck lands south of the lake to plant crops.Eventually, the settlement began to movesouth from Lake Jesup, and by 1875 a postoffice, two general stores, several houses,and a hotel had been built in the vicinity ofLake Charm. In 1879, the post officemoved south from Lake Charm, and thenew settlement was named Oviedo by thepostmaster, after a university town inSpain. Farmers initially attempted to plantsome of the crops that they wereaccustomed to growing in more northernclimes, such as cotton and sugar cane, butthese did not prove successful. They laterfound that citrus and vegetables were muchmore appropriate crops for the area, and anexplosion of agriculture began, andcontinued for many years. By 1950, whenOviedo had a population of only 1,800,nearly one million crates of celery and one-third million crates of citrus were beingshipped out annually.

Agriculture remains important in Oviedo tothis day, but plays a much smaller role thanit did in earlier years. Much of the growingin the area now takes place in BlackHammock, which is located north of the cityof Oviedo near the southeast shore of LakeJesup. This area was once important as acenter for watercress production, but this

form of agriculture has now been largelydiscontinued in Black Hammock because ofthe tremendous amount of groundwaterneeded to maintain the watercress fields.Currently, strawberries and other row crops,citrus, and many types of ornamentalshrubs and trees are grown here. Farmlandin the area is extensively canalized, withthe ditches flowing north into the lake.

The story of Oviedo in the 1990s is one ofpopulation growth. Beginning with theestablishment of the University of CentralFlorida several miles south of Oviedo, andthe later development of several high-techindustries in the same vicinity, Oviedo soonbecame a “boom town,” as residentialdevelopments sprang up rapidly inresponse to population growth in theOrlando area. Today, Oviedo has nearly21,000 residents and is growing by leapsand bounds. Its 6,850 households have amedian annual income of over $40,000.Population density is roughly 460 personsper square mile (Oviedo Chamber ofCommerce 1997).

Fort Florida on the St. Johns River at Sanford(Photo courtesy Florida State Archives.)

Across Lake Jesup to the northwest is thecity of Sanford. The area was first settled inthe 1830s as a U.S. Army outpost, andnamed Fort Mellon after Captain CharlesMellon, who was killed in an Indian attack.The name was later changed to Mellonville.The city was incorporated in 1877 andnamed Sanford after Henry S. Sanford,who bought 12,500 acres in the Mellonvillevicinity and instituted the raising of citrus

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and other crops in the area. Prior to the bigfreeze of 1895, Sanford was the largestshipper of citrus in the world. After thefreeze, however, farmers in the Sanfordarea turned to vegetables (especiallycelery), and also to ferns. A number ofcattle farms were also established.Population growth in Sanford has beenmore modest than that south of the lake inthe Orlando metropolitan area. However,there are currently more than 35,000residents living in Sanford, at a density ofapproximately 700 people per square mile.It is expected that population growth inSanford will accelerate when SR 417 (theGreeneway) is extended northwest to I-4 inthe near future, making the commute fromOrlando to Sanford much more convenient.

The youngest of the major urban centerslocated on the shores of Lake Jesup is thecity of Winter Springs. Originally a part ofOrlando, it went by the name “The NorthernVillage of Orlando.” It was incorporated asa city in 1959. In 1972, its citizens voted tochange the name of the town to WinterSprings. Although there is some agriculturein the area, the defining aspect of WinterSprings’ story is urban growth. Since 1970,it has seen a population growth of morethan 800%. Its current population exceeds27,000, with some 10,000 households anda population density of 1,735 persons persquare mile. Winter Springs is currently thelargest municipality in Seminole County.Despite the fact that a considerable portionof the residential development in WinterSprings has taken place since the 1986 stormwater ruling came into effect, thepotential for nonpoint source runoff fromextensive areas of impervious surface ishigh.

Another important chapter in the saga ofLake Jesup’s deterioration deals with thephysical alteration of its connection with theSt. Johns River. In the early part of thetwentieth century, two canals were cutthrough the marshy peninsula formed at theconfluence of the lake and the river tofacilitate boat traffic. The Old Ferry Canalprobably was cut through shortly before theturn of the century by steamboatsrepeatedly traversing the marsh during high

water. Government Cut Canal, a moreofficial endeavor, was probably constructedsometime in the late 1910s or early 1920s.By 1908, a causeway had been built acrossthe area, with bridges spanning bothchannels (inflow and outflow) of the river. Inthe early 1950s, the inflow (south) channelof the river was filled in, and the currentbridge over the other channel built. Thiseffectively cut off the flow of the St. Johnsfrom Lake Jesup, sending it throughGovernment Cut, and leaving only the northchannel connecting the lake to the river.

Thus, a long history of intense agriculture inthe watershed, recent burgeoningpopulation growth in surrounding cities, andsevere restriction of the lake’s outlet to theSt. Johns River have undoubtedlycontributed to the hypereutrophication ofLake Jesup.

Sanford steamboat launch,postcard, circa 1895.

(Photograph courtesy ofFlorida State Archives.)

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Lake Jesup Tributaries Drainage Basins

HOWELL CREEK

GEE CREEK

BEAR CREEK

LAKE JESSUP OUTLET

SOLDIER CREEK REACH

SALTCREEK

PHELPS

CREEK

ELDERSPRINGS

RUN CHUB CREEK

SWEETWATER

CREEK S

HORTCUT

CANAL

WHARF CREEK

UNNAMED DITCH

BLACK

SWEETWATER

CREEK

2 0 2 4 6 8 10 12 14 16 18 20 22 Miles

N

EW

S

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Locator Map

Lake Jesup

Seminole County

Howell Creek Basin

N

EW

S

Basin Land UseArea = 34.04 square milesÊÚ = FDEP Sampling Site

ÊÚ

1 0 1 2 3 4 5 6 7 8 Miles

Percent Land Use

Urban

Agriculture

Rangeland

Upland Forests

Water

Wetlands

Barren Lands

Utilit ies

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RESULTS

Howell Creek

Howell Creek originates in a series of smalllakes in the vicinity of downtown Orlando.The stream then passes through LakeHowell at the southern edge of the city ofCasselberry, and afterwards through theWinter Springs/Tuskawilla area beforeflowing into Lake Jesup. Land use in thearea is approximately two-thirds residentialdevelopment, with most of the remainderbeing undeveloped land. Numerousnonpoint sources drain into Howell Creek,especially in the extensively urbanizedupper reaches of the stream.

Howell Creek at SR 434

Despite this, biological and water chemistrysampling results suggest that water qualityin Howell Creek is fairly good at this time.The SCI ranked the Howell Creek site atSR 419 as “good,” with a total of 19macroinvertebrate taxa collected in thesubsample, including three from the EPT(larval mayflies, stoneflies, and caddisflies)group, and 14 points scored for FloridaIndex (good water quality) animals. At thetime of sampling, there had been recentheavy rains, and the water level was high.This caused some habitat types to belargely inaccessible to sampling withdipnets, and might have caused the SCIscores to be somewhat lower than theymight otherwise have been. Themacroinvertebrate fauna was dominated atthis site by fingernail clams (Pisidiidae),followed by the riffle beetle Microcylloepuspusillus.

All physical parameters measured werewithin normal ranges. Water chemistryanalyses showed that nutrient levels werenot especially high, most being roughly inthe 50th percentile range compared withother Florida streams (see below andAppendix 1). Fecal coliform bacterialcounts were fairly high (320colonies/100mL), but did not exceed statestandards for Class III waters. Habitatquality was good at the site.

Sampling was also carried out fartherupstream in Howell Creek at Winter SpringsBoulevard. The SCI assessment suggesteda healthy macroinvertebrate communityhere, rating it as “very good.” There were21 different taxa collected, seven of whichwere EPT. The Florida Index yielded ascore of 11 at this site. The most commonmacroinvertebrate species collected wasMicrocylloepus pusillus, the riffle beetle.

Water chemistry measurements weresimilar to those seen at the other HowellCreek site. Most were in about the 50thpercentile range or less, except forturbidity, which was in the 77th percentilewhen compared with other Florida streams.

Dissolved oxygen, conductivity, pH, waterclarity, and flow were all good. The habitatassessment, however, was suboptimal dueto a minimal riparian buffer zone and areasof erosion, plus a lack of some instreamhabitat types.

Howell Creek at Winter Springs Blvd.

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KEY ASSESSMENT PARAMETERS

Howell Creek at SR 4347/9/96

Howell Creek at Winter Springs Blvd.8/18/97

Biology Biology SCI score 23 (good) SCI score 27 (very good)

Florida Index 10 Florida Index 11 EPT 2 EPT 7

number of taxa 19 number of taxa 21 dominant taxon Pisidiidae dominant taxon Microcylloepus pusillus

Chemistry (value) (percentile)* Chemistry (value) (percentile)* dissolved oxygen 5.60 mg/L 50 dissolved oxygen 6.02 mg/L 60

conductivity 162 Τmhos/cm 30 conductivity 173 Τmhos/cm 30 pH 7.0 std. units 50 pH 6.9 std. units 50

unionized NH3 0.0003 mg/L 55 unionized NH3 0.0002 mg/L 50 TKN 0.67 mg/L 30 TKN 1.0 mg/L 50

nitrate/ nitrite 0.11 mg/L 60 nitrate/ nitrite 0.11 mg/L 60 total phosphorus 0.11 mg/L 60 total phosphorus 0.07 mg/L 50 fecal coliforms 320 colonies/100mL 85 fecal coliforms 320 colonies/100mL 85

Habitat Habitat assessment score 117 out of 145 points assessment score 102 out of 145 points

* Approximate percentile ranking compared with other Florida streams.

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Locator Map

Lake Jesup

Seminole County

Bear Creek Basin

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ÊÚ

1 0 1 2 3 4 Miles

Percent Land Use

Urban

Agriculture

Rangeland

Upland Forest s

Water

Wetlands

Barren Lands

Utilities

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Bear CreekThis stream originates at Bear Gully Lakeat the southern edge of Seminole County inthe Goldenrod area. Its middle section,canalized about 50 years ago, is oftencalled Bear Gully or Bear Gully Creek.Shortly beyond the point where it is joinedby Lightwood Knox (also known as LighterKnot) Canal just west of Oviedo, its courseagain becomes natural and remains so untilit flows into Howell Creek in the Tuskawillaarea of Winter Springs. The sampling site isa short distance upstream from thisconfluence. Residential and agriculturaldevelopment account for two-thirds of landuse in the Bear Creek watershed. Althoughsurrounded by urban development in theupper and lower segments of its watershed,a natural wetland buffer has beenpreserved (especially in its lower reaches)where Bear Creek flows through theseneighborhoods. For the most part, this isnot true in the creek’s canalized middlesection, where the land use is primarilyagriculture. A shopping mall with aneventual area of 1.2 million ft2 is currentlybeing built within the Bear Creek watershednear Oviedo.

Bear Creek at Northern Way

The results of biological sampling at BearCreek suggest a healthy macroinvertebratecommunity in this stretch of the stream. TheSCI rated Bear Creek as “very good.” Therewere 27 macroinvertebrate taxa found inthe subsample, five from the EPT group.The site received a Florida Index score of11. The most common invertebratecollected was the riffle beetleMicrocylloepus pusillus.

Habitat quality at the site was very good,with plentiful submerged roots and snagsavailable for colonization by macroinvert-ebrates. The riparian zone is well preservedin this stretch of the creek, reducing theeffects of nonpoint source runoff. The over-all habitat rating was 131 out of a possible145 points, the best seen in this survey.

Water chemistry data reveal that the levelsof nutrients present here all exceed the50th percentile ranking compared withother Florida streams. None, however, wasextremely high, and none constituted aviolation of water quality standards. This istrue also for fecal coliform bacteria, whichmeasured in the 91st percentile, but did notexceed Class III freshwater standards.Physical water quality measurements weregood at Bear Creek. Dissolved oxygen, pH,conductivity, and water temperature wereall within normal ranges. Water velocity wasamong the highest recorded in this survey.

KEY ASSESSMENT PARAMETERS 9/24/97Biology SCI score 29 (very good) Florida Index 11 EPT 5 number of taxa 27 dominant taxon Microcylloepus pusillusChemistry (value) (%ile)* dissolved oxygen 6.60 mg/L 67 conductivity 230 Τmhos/cm 38 pH 7.16 std. units 64 unionized NH3 0.0005 mg/L 65 TKN 0.81 mg/L 40 nitrate/ nitrite 0.15 mg/L 63 total phosphorus 0.14 mg/L 71 fecal coliforms 540 colonies/100mL 92Habitat assessment score 131 out of 145 points* Approximate percentile ranking compared withother Florida streams.

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Percent Land Use

Urban

Agr iculture

Rangeland

Upland Forests

Water

Wetlands

Barren Lands

Ut ilities

1 0 1 2 3 4 Miles

ÊÚ

= FDEP Sampling SiteÊÚ

Basin Land UseArea = 18.54 square miles

N

EW

S

Soldier Creek Basin

Lake Jesup

Seminole County

Locator Map

14

Soldier Creek

Also known as Soldier’s Creek, this streamenters Lake Jesup at its far western edge,where it joins with its sister stream, GeeCreek. Residential development accountsfor roughly 60% of land use in the SoldierCreek drainage basin. However, fairlyextensive wetlands are also present,especially in the downstream section of thestream, a large portion of which iscontained within Seminole County’sSoldier’s Creek Park.

Soldier Creek downstream of SR 419

Soldier Creek received a Stream ConditionIndex rating of 25, putting it in the “good”category. Of the 24 macroinvertebrate taxacollected at this site, three were membersof the EPT group. A Florida Index score of7 was determined for the stream. As seenin other streams in the area, the dominantspecies present was the riffle beetleMicrocylloepus pusillus. The second mostabundant was the larva of the blackfly,Simulium.

On the whole, nutrient values were slightlyhigh in water samples taken from the creek.Total ammonia, unionized ammonia, andnitrate/nitrite were at the 50th percentilelevel or higher compared with other Floridastreams. The total phosphorus reading wasquite high at 0.21 mg/L, or in the 80thpercentile. However, chlorides, sulfates,and total Kjeldahl nitrogen werecomparatively lower in concentration. Fecalcoliform counts were high (620colonies/100 mL), but did not exceed state

standards. All physicochemical parametersmeasured were within normal ranges.

The habitat assessment yielded a score of131 out of a possible 145 points. This wasa tie with Bear Creek for the best habitatrating seen in this survey. Minor habitatsmothering due to some bank instabilityprevented it from receiving a perfect score.

KEY ASSESSMENT PARAMETERS 7/9/96Biology SCI score 25 (good) Florida Index 7 EPT 3 number of taxa 24 dominant taxon Microcylloepus pusillusChemistry (value) (%ile)* dissolved oxygen 6.10 mg/L 55 conductivity 163 Τmho/cm 68 pH 6.97 std. units 50 unionized NH3 0.0003 mg/L 55 TKN 0.82 mg/L 40 nitrate/ nitrite 0.13 mg/L 60 total phosphorus 0.21 mg/L 80 fecal coliforms 620

colonies/100mL95

Habitat assessment score 131 out of 145 points* Approximate percentile ranking compared withother Florida streams.

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Locator Map

Lake Jesup

Seminole County

Gee Creek Basin

N

EW

S


ÊÚ

1 0 1 2 3 4 5 Miles

Percent Land Use

Urban

Agriculture

Rangeland

Upland Forests

Water

Wetlands

Barren Lands

Utilities

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Gee Creek

The eighteen-square-mile drainage area ofGee Creek includes virtually all of the cityof Casselberry, plus portions of Longwoodand Winter Springs. Approximately 65% ofthe basin is urban, with the remainderbeing mostly undeveloped wetlands,forests, and water. Gee Creek properoriginates at Lake Kathryn in Casselberry. Itflows northward out of the lake through thewestern part of Winter Springs to unite withSoldier Creek at the extreme western tip ofLake Jesup.

Gee Creek at SR 419/434

The largest number of macroinvertebratetaxa collected in this survey wasencountered here. There were 28 differenttaxa collected in the subsample. Of these,three were members of the EPT group.Thirteen Florida Index points were scored,again the highest seen in this study. TheStream Condition Index score for this sitewas 27, placing it in the “very good”category. The dominant macroinvertebratespecies was the midge Polypedilumconvictum group, followed by the rifflebeetle Microcylloepus pusillus.

At the time of sampling, nutrient values,especially the various forms of nitrogen,were fairly high. Most were in the 65th to70th percentile range. Total Kjeldahlnitrogen, however, was relatively low, onlyin the 20th percentile range compared toother Florida streams. On the other hand,the calculated value for unionized ammoniawas very high, in the 90th percentile range.This calculation is based on temperature,

pH, and total ammonia concentration. ThepH measured here was quite basic, 8.25,whereas the total ammonia value was 0.05mg/L, in the 65th percentile. Unionizedammonia is considered toxic to aquatic lifein high concentrations, but no evidence ofdegradation of the aquatic community wasseen at this time. The high pH and nutrientvalues are probably due to algae blooms inupstream lakes. Fish kills due to algaeblooms have occurred recently in LakeKathryn.

Modest concentrations of chlorides andsulfates were found at Gee Creek. Turbiditywas also quite low. Alkalinity was relativelyhigh at this site, however, as were bothfecal and total coliform concentrations. Innone of these cases, though, was aviolation of surface water quality standardsdetected.

The habitat assessment for Gee Creek atSR 419/434 gave it a score of 111 out of apossible 145, or 77%. This placed it at thelow end of the “optimal” habitat scorerange. Certain areas of erosion and theresulting siltation effect on habitats, alongwith a reduced riparian buffer zone,detracted somewhat from the overallhabitat score for this site.

KEY ASSESSMENT PARAMETERS 3/3/97Biology SCI score 27 (very good) Florida Index 13 EPT 3 number of taxa 28 dominant taxon Polypedilum convictum gr.Chemistry (value) (%ile)* dissolved oxygen 6.11 mg/L 60 conductivity 277 Τmhos/cm 42 pH 8.25 std. units 99 unionized NH3 0.0045 mg/L 95 TKN 0.46 mg/L 20 nitrate/ nitrite 0.20 mg/L 70 total phosphorus 0.14 mg/L 70 fecal coliforms 170

colonies/100mL70


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Lake Jesup

Seminole County

Percent Land Use

Urban

Agriculture

Upland Forests

Water

Wetlands

Utilities

ÊÚ


ÊÚ = FDEP Sampling Site

Locator Map

N

EW

S

Sweetwater Creek Basin

0.6 0 0.6 1.2 Miles

18

Sweetwater Creek

The first of four streams or canals sampledin the Black Hammock area north ofOviedo, Sweetwater Creek originates indowntown Oviedo. It flows throughresidential and wetland areas beforereaching Black Hammock, where it hasbeen modified into a roadside ditch whichdrains north into Lake Jesup almost duesouth of Bird Island. The 2.5 square milesof land area that it drains is 50% urbandevelopment, with the remainder aboutevenly divided between agriculture, uplandforests, and wetlands. Unlike the creeks inthe Winter Springs area, Sweetwater Creek(as well as the other Black Hammockcreeks) does not flow from or through anylakes, but apparently is fed by groundwatersurfacing in wetlands and by runoff.

Sweetwater Creek at Deleon Street

Fifteen macroinvertebrate taxa werecollected at Sweetwater Creek: ninedipterans, three oligochaetes, one mollusk,and two odonates. This is the lowestnumber of taxa seen at any of the elevensites in this survey. In addition, this was theonly site where there were no mayflies orcaddisflies collected (i.e., zero EPT). TheFlorida Index score was eight. Thehydrobiid snail Pyrgophorus platyrachiswas the dominant taxon, making up 52% of

the individuals collected. SCI assessmentranked the site as suboptimal, placing it inthe “good” category.

Nutrients were very high at this site.Concentrations of total ammonia, unionizedammonia, nitrate/nitrite, and totalphosphorus were all in the 90th percentilerange or higher. Alkalinity, total Kjeldahlnitrogen, chloride, and sulfateconcentrations all ranged between the 75thand 80th percentiles. Fecal coliforms werealso quite high, showing counts of 740colonies per 100 mL. In none of thesecases, however, was a current water qualitystandard violated.

Habitat quality at Sweetwater Creek wassuboptimal. A lack of riparian buffer zoneon one side, substantial erosion and habitatsmothering, and a poor quality streamsideplant community contributed to a score of76 out of a possible 145 points, or 52%.

KEY ASSESSMENT PARAMETERS 8/12/97Biology SCI score 21 (good) Florida Index 8 EPT 0 number of taxa 15 dominant taxon Pyrgophorus platyrachisChemistry (value) (%ile)* dissolved oxygen 5.99 mg/L 55 conductivity 709 Τmhos/cm 68 pH 7.19 std. units 81 unionized NH3 0.0019 mg/L 90 TKN 1.4 mg/L 75 nitrate/ nitrite 0.75 mg/L 92 total phosphorus 0.42 mg/L 90 fecal coliforms 740

colonies/100mL95


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Lake Jesup

Seminole County

Percent Land Use

Urban

Agriculture

Upland Forests

Water

Wetlands

ÊÚ



Locator Map

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Shortcut Canal Basin

0.5 0 0.5 1 Miles

20

Shortcut CanalAs the name implies, this is not a naturalwaterbody, but a canal (or more accurately,a series of canals) which flows north intoLake Jesup. The two-square-mile drainagearea is made up of 55% agricultural landdrained by the canals, about 20%residential development centered at LakeCharm and the western part of BlackHammock, and roughly 25% undevelopedland, which is chiefly wetlands. With theexception of a half-mile stretch where itflows in an ill-defined course through asmall wetland, it is made up of severalinterconnected box-cut roadside ditcheswhich drain farmland.

Shortcut Canal at Howard Avenue

Biological sampling carried out at ShortcutCanal shows that the man-made waterbody is in fairly good ecological conditioncompared with other streams in the area.The SCI assessment gave a score of 25,placing it in the “good” category. Of the 21macroinvertebrate taxa collected in thesubsample, four were from the EPT group.The Florida Index score for Shortcut Canalwas 11, equal to those from Bear andHowell Creeks. The dominant taxon wasthe amphipod Gammarus sp.Chemical water quality sampling showedmixed results at this site. Total phosphorusand the calculated unionized ammoniavalues were quite high -- greater than the80th percentile compared with other Floridastreams. On the other hand, Kjeldahlnitrogen and nitrate/nitrite measurementswere average, in the 54th and 57thpercentiles, respectively. There were 420colonies/100mL fecal coliforms, which isquite high (88th percentile), but notexceeding water quality standards.

Both chlorides and sulfates (and thusconductivity) were very high in this stream.In this area, saline water is present in thelower portions of the surficial aquiferbeneath the freshwater layer. Excessiveuse of groundwater in the area foragriculture, plus extensive canalization ofthe land, have exacerbated saltwaterintrusion into fresh groundwater sources.This has resulted in very high levels ofsulfates and chlorides in this and otherstreams in the area (especially those to theeast of Shortcut Canal), as well as thecontamination of drinking water sources forresidents in the eastern portion of BlackHammock. Thus, the chloride level inShortcut Canal is in the 99th percentilecompared with other Florida streams.Sulfates are in the 90th percentile.Shortcut Canal’s habitat assessment scorewas fairly low. Being a man-made ditch, itscored relatively poorly on all portions ofthe habitat assessment. This wasespecially true regarding riparian bufferzone width, which was only three meters onone side, with citrus groves on both sidesof the canal. The habitat assessment scorewas 87 out of a possible 145 points, or60%.

KEY ASSESSMENT PARAMETERS 9/8/97Biology SCI score 25 (good) Florida Index 11 EPT 4 number of taxa 21 dominant taxon Gammarus sp.Chemistry (value) (%ile)* dissolved oxygen 4.68 mg/L 35 conductivity 1910 Τmhos/cm 90 pH 7.24 std. units 90 unionized NH3 0.0013 mg/L 82 TKN 0.52 mg/L 54 nitrate/ nitrite 0.11 mg/L 57 total phosphorus 0.30 mg/L 84 chlorides 580 mg/L 99 sulfates 87 mg/L 90 fecal coliforms 420

colonies/100mL88


21

Lake Jesup

Seminole County

Percent Land Use

Urban

Agriculture

Rangeland

Upland Forests

Water

Wetlands

ÊÚ



Locator Map

N

EW

S

Salt Creek Basin

0.5 0 0.5 1 1.5 2 2.5 Miles

22

Salt Creek

This stream is aptly named, since it is fedby base flow from partially salinegroundwater, as mentioned earlier. Itoriginates near SR 426 just east of Oviedoonly about a mile from theEconlockhatchee River. A large portion ofthe stream has been canalized, where itfunctions as a roadside ditch and receivesinput from a number of other smallerditches. Only where it enters the marshyarea near the lake has it not been altered.The watershed of this stream is onlysparsely developed. More than 75% of theland in the Salt Creek basin is upland forestand wetlands. About 15% is low-densityurban development. The remaining landuse is agricultural and rangeland.

Salt Creek downstream of Packard Ave.

Salt Creek received a poor StreamCondition Index rating. Nineteenmacroinvertebrate taxa were collected inthe sample, scoring only five Florida Indexpoints (the lowest seen in this study). Therewere only two animals from the EPT groupfound here. Like Sweetwater Creek, thedominant macroinvertebrate species wasthe hydrobiid snail Pyrgophorus platyrachis.

Nitrogen levels were moderate to high atSalt Creek. Total Kjeldahl nitrogen was thehighest (2.9 mg/L), whereas thenitrate/nitrite concentration wasintermediate (0.16 mg/L). As would beexpected from the saline groundwaterinfluence, chloride and sulfateconcentrations were very high (810 and150 mg/L respectively). Both were in the

99th percentile range compared with otherFlorida streams. Total phosphorus was alsovery high in this creek, 0.35 mg/L, or the87th percentile. Specific conductance wasmeasured at 3000 Τmho/cm. The water wasvery darkly tannic in Salt Creek. The fecalcoliform concentration, though fairly high,did not exceed state standards.

The habitat quality, though not excellent,did fall within the low part of the optimalrange. Despite the fact that the stream’scourse has largely been altered, this wasdone many years ago, allowing for somerecovery, and the surrounding area islargely undeveloped. Consequently, SaltCreek received a somewhat higher habitatscore than other area streams and canals.

KEY ASSESSMENT PARAMETERS 8/12/97Biology SCI score 17 (poor) Florida Index 5 EPT 2 number of taxa 19 dominant taxon Pyrgophorus platyrachisChemistry (value) (%ile)* dissolved oxygen 5.31 mg/L 45 conductivity 3000 Τmho/cm 94 pH 6.88 std. units 45 unionized NH3 0.0014 mg/L 82 TKN 2.9 mg/L 95 nitrate/ nitrite 0.16 mg/L 64 total phosphorus 0.35 mg/L 87 chlorides 810 mg/L 99 sulfates 150 mg/L 99 fecal coliforms 470

colonies/100mL90


23

Lake Jesup

Seminole County

Percent Land Use

Urban

Agriculture

Rangeland

Upland Forests

Water

Wetlands

ÊÚ Basin Land UseArea = 3.60 square miles


Locator Map

N

EW

S

Black Sweetwater Creek Basin

1 0 1 Miles

24

Black Sweetwater Creek

Identified on some maps as SweetwaterCreek (though a separate stream entirelyfrom the one of the same name discussedpreviously), Black Sweetwater Creek isbasically a network of ditches which drainfarmland in Black Hammock. Originating atthe outskirts of Oviedo near SR 426, itdrains 3.6 square miles of land, roughly60% of which is undeveloped. Agricultureaccounts for 23% of the land use, withmost of the rest being devoted to urbandevelopment.

Black Sweetwater Cr. downstream of Howard Ave.

Black Sweetwater Creek scored very lowon the biological assessment. It received anSCI score of 15, placing it in the “poor”category. Of the 19 macroinvertebrate taxacollected, there was only one EPT, themayfly Caenis diminuta. Only six FloridaIndex points were scored. The hydrobiidsnail Pyrgophorus platyrachis wasdominant, making up 73% of the sample.The results suggest a poor and imbalancedmacroinvertebrate community.

The results of water chemistry samplingwere generally also poor. Levels ofunionized ammonia (calculated) and totalphosphorus were fairly high. As expecteddue to saline groundwater input, thechloride and sulfate measurements werealso quite high.

Black Sweetwater Creek was the only sitein this survey where the dissolved oxygenlevel was well below the state standard forClass III fresh waters (5.0 mg/L). Theoxygen level found here was a very low

1.89 mg/L, a concentration at which manyaquatic organisms cannot survive.

In addition, the fecal coliform concentrationin the water taken at this site was 1300colonies per 100mL. This is a definiteexceedence of the allowable thresholdunder state standards, which is 800colonies/100mL.

The habitat assessment at this site wasequally abysmal. Because the channelizedstream had extensive silt smothering, verylow water velocity (0.06 m/s), and a riparianzone plant community that lacked diversityand contained a number of exotic species,the habitat assessment score was 65 out of145 possible points. This gave it a rating of“marginal.”

KEY ASSESSMENT PARAMETERS 9/24/97Biology SCI score 15 (poor) Florida Index 6 EPT 1 number of taxa 19 dominant taxon Pyrgophorus platyrachisChemistry (value) (%ile)* dissolved oxygen 1.89 mg/L 5 conductivity 1910 Τmhos/cm 90 pH 6.99 std. units 50 unionized NH3 0.0007 mg/L 71 TKN 0.47 mg/L 20 nitrate/ nitrite 0.06 mg/L 43 total phosphorus 0.35 mg/L 87 fecal coliforms 1300

colonies/100mL99

Habitat assessment score 65 out of 145 points* Approximate percentile ranking compared with other Florida streams.

Black Sweetwater Creek upstream of Howard Ave.

25

Locator Map

Lake Jesup

Seminole County

Phelps Creek Basin

N

EW

S

Basin Land UseArea = 5.95 square milesÊÚ = FDEP Sampling Site ÊÚ

0.5 0 0.5 1 1.5 Miles

Percent Land Use

Urban

Agr iculture

Rangeland

Upland Forests

Water

Wetlands

Barren Lands

Sanford Airport

26

Sanford Airport Ditch

A number of interconnected roadsideditches which flow through the SanfordOrlando Regional Airport culminate in thisman-made ditch, which flows south fromthe airport to empty into Lake Jesup at themouth of Phelps Creek. The watershedalso includes Golden Lake south of theairport, which has an outlet into the ditchsystem. Approximately 30% of the land usein the Airport Ditch/Phelps Creek watershedis commercial (airport), with an equalamount being residential. The remainingland use is roughly 20% each ofundeveloped land and field or pasture. Thesample site is in a low-density urban areanear the north shore of the lake.

Sanford Airport Ditch at Pineway Road

Twenty-two invertebrate taxa werecollected in the sample taken here.Included in this number were four from theEPT group. A total of five Florida Indexpoints was scored. The overall SCIassessment score was 21, giving SanfordAirport Ditch a “good” rating. The dominantspecies present in the sample was the rifflebeetle Microcylloepus pusillus, whichaccounted for 38% of the individualscollected.

Despite the fact that its flow at this point ismade up almost entirely of runoff from thevicinity of Sanford Orlando RegionalAirport, water chemistry analysessuggested fairly good water quality in theAirport Ditch. Both nitrate/nitrite and totalphosphorus values were the lowestmeasured in this study. All other waterchemistry parameters showed low or

average values compared with otherFlorida streams. However, the fecalcoliform level in the stream (710colonies/100mL) ranked in the 94thpercentile. Although high, this was not inviolation of current water quality standards.

Even though the water quality wasreasonably good, the habitat quality wasrelatively poor. Due to low water velocity, avery reduced riparian zone buffer, and poorriparian vegetative community, the sitereceived a score of 86 out of a possible145 points, giving it a suboptimal rating.

KEY ASSESSMENT PARAMETERS 8/25/97Biology SCI score 21 (good) Florida Index 5 EPT 4 number of taxa 22 dominant taxon Microcylloepus pusillusChemistry (value) (%ile)* dissolved oxygen 6.72 mg/L 69 conductivity 190 Τmhos/cm 33 pH 6.97 std. units 50 unionized NH3 0.0002 mg/L 50 TKN 0.49 mg/L 20 nitrate/ nitrite 0.03 mg/L 25 total phosphorus 0.03 mg/L 20 fecal coliforms 710

colonies/100mL94


Aerial view of Sanford Orlando Regional Airport showingditch system (thin black lines). Golden Lake is at lowercenter.

27

Lake Jesup

Seminole County

Percent Land Use

Urban

Agriculture

Rangeland

Upland Forests

Water

Wetlands

Barren Lands

Utilities

ÊÚ



Locator Map

N

EW

S

Elder Springs Run Basin

1 0 1 2 Miles

28

Elder Springs Run

This watershed is made up of two forks.The western fork receives input fromseveral small springs in the Elder Springsarea south of Sanford. The eastern forkoriginates at Lake Ada just west of US Hwy17/92 and flows south to where it joinsElder Springs Run proper about a mileabove Lake Jesup. At several points in theeastern portion of the watershed, thestream is canalized, serving as a roadsidedrainage ditch. The combined stream flowsinto the lake at Seminole County’s LakeJesup Park. One-half of the land use in theElder Springs Run watershed is urban.Roughly 15% is devoted to agriculture.Most of the remainder is undeveloped land.

Elder Springs Runupstream of Myrtle Avenue

Elder Springs Run received a “good” ratingon the SCI. There were 24macroinvertebrate taxa collected, whichincluded three from the EPT group. TheFlorida index score was nine. Once again,the dominant invertebrate taxon presentwas Microcylloepus pusillus, the rifflebeetle.

Water chemistry results suggest fairly goodwater quality. Percentile rankings for theseparameters ranged from the 46th to the71st. As seen before, the concentration offecal coliform bacteria in the water samples

was very high (510 colonies/mL), but notabove the level allowed by current Floridarules.

At the sampling site, the habitat evaluationproduced good results. Out of a possible145 points, the site scored 121, placing it inthe mid-range of the “optimal” category. Anarrow buffer zone and poor riparian plantcommunity kept Elder Springs Run fromreceiving a very high habitat assessment.

KEY ASSESSMENT PARAMETERS 8/25/97Biology SCI score 25 (good) Florida Index 9 EPT 3 number of taxa 24 dominant taxon Microcylloepus pusillusChemistry (value) (%ile)* dissolved oxygen 6.45 mg/L 65 conductivity 292 Τmhos/cm 43 pH 6.95 std. units 50 unionized NH3 0.0003 mg/L 55 TKN 1.3 mg/L 70 nitrate/ nitrite 0.07 mg/L 46 total phosphorus 0.15 mg/L 71 fecal coliforms 510

colonies/100mL90


Elder Springs Run at Nolan Road,upstream of sample site

29

DiscussionThe sampling results show that Lake Jesuptributary streams located near to oneanother have similar water qualitycharacteristics. With a few exceptions, thestreams in the Black Hammock vicinityresemble one another in water quality, asdo those in the Winter Springs/Casselberryarea. Not surprisingly, the land uses withinthe watersheds of those streams whichshow similar water quality also tend to besimilar. The two streams near Sanford,although very different in origin andhydrology, grouped closely together inwater quality as well.

Winter Springs area streamsThe streams in the Winter Springs area(Howell, Bear, Soldier, and Gee Creeks)are influenced most by residentialdevelopment. The mean percentage ofresidential land use in the four watershedsis 59% (maxi-mum: Howell Creek, 68%;minimum: Bear Creek, 46%). Fortunately,most of the residential development in thisarea is fairly recent (at least in the lowerreaches of these stream basins where theywere sampled). Florida’s stormwater rulewent into effect in 1986. Consequently,modern stormwater retention methods wereused in many of the developments in thearea, leading to a reduction in the amountof nutrient- and bacteria-laden stormwaterthat would otherwise enter these streamsduring storm events. Despite this, nutrientlevels as a whole were somewhat higherthan the average for all Florida streams,particularly for total ammonia, nitrate/nitrite,and total phosphorus. Fecal coliforms werealso fairly high in the area, with an averagecount of approximately 360colonies/100mL, or the 85th percentilecompared with other streams in the state.The highest of the four, Soldier Creek, hada level of 620 colonies/ 100mL. The SoldierCreek basin has the largest percentage ofolder homes of the four, and thus probablyhas more septic tanks in use within thewatershed.

These somewhat elevated nutrient andcoliform bacteria levels did not appear tohave had substantial effects on the macro-invertebrate communities present in these

streams. Results of the biological assess-ment were basically good. Particularly atBear Creek, Gee Creek, and Howell Creekat Winter Springs Boulevard, there werehigh numbers of macroinvertebrate taxa,including quite a few which are sensitive topollution, and are thus indicators of goodwater quality. Interestingly, a dominantmacroinvertebrate at all of the sites was theriffle beetle Microcylloepus pusillus. Thisbeetle is a member of the family Elmidae,the only truly aquatic beetles. The adults,tiny, hard-bodied, slow-moving beetles withlong claw-bearing legs, respire by collectingair on patches of dense microscopic hairstermed “hydrofuges.” The elongate larvaehave gills in a cavity at the end of theabdomen which has a hinged door that canbe opened or closed, or used as a fan tomove water over the gills at times of lowflow. Elmids are intolerant of many types ofpollution, especially when it contains soapsor detergents (Brown 1972). Theirrespiratory physiology limits theirdistribution to habitats which are oxygen-rich (Gnilka & Gnilka 1982). At none ofthese sites was dissolved oxygen below thestate standard of 5 mg/L.

Since there are no longer permitted pointsource discharges into any of these WinterSprings/Casselberry area streams, thebiggest challenge to the ecological healthof these systems is the intensity of urbandevelopment within the watershed. Habitatalteration and nonpoint source runoffproblems due to extensive areas ofimpervious surface are characteristic ofurban development, and are quite evidentin the upper reaches of these streams.

Suggestions for the improvement of theenvironmental health of these tributaries ofLake Jesup include appropriate mainten-ance of stormwater retention systemswhere they are present, establishment ofstormwater management improvementswhere they are not, active or passiverejuvenation of the riparian zone of lakesand streams within the drainages,agricultural BMPs, and the preservation ofremaining wetland areas.

30

Circa 1972 Circa 1996

The aerial photographs above show part of the Winter Springs/Oviedo area at different periods. Notice the urbanization of areas that drain to Lake Jesup (at top left).

31

Oviedo area streams

In contrast to the relatively good quality ofwater flowing into Lake Jesup from theWinter Springs area, the water quality instreams in Black Hammock is generallypoor. As a group, these four streams(Sweetwater, Black Sweetwater, and SaltCreeks and Shortcut Canal) werecharacterized by a poor biologicalcommunity, low dissolved oxygen, highnutrients and fecal coliforms, and highlyaltered and degraded instream and riparianzone habitat.

The biological assessment showed thatthese streams supported comparativelysmall numbers of macroinvertebrate taxa,few to none of which were the sensitiveEPT (mayfly, stonefly, and caddisfly larvae)species. Degradation was especiallyapparent at Salt, Sweetwater, and BlackSweetwater Creeks, where the macro-invertebrate community was dominated by

the hydrobiid snailPyrgophorusplatyrachis. Thissnail is common instreams with lowflow; soft, siltybottoms with large

amounts of organic material; high chloridecontent in the water; and high turbidity(Thompson 1968). All three streams showthese characteristics. Shortcut Canal,though certainly not pristine, rated betterthan the other three. All biologicalparameters were better, and the dominantmacroinvertebrate was the amphipod(crustacean) Gammarus sp. The hydrobiidsnail Pyrgophorus platyrachis accountedfor only 2.4% of the macroinvertebratescollected at Shortcut Canal.

Because this area is characterized bypartially saline groundwater, it was thoughtthat the poor biological results from thesestreams might be tied in part to the difficultyfreshwater organisms might have in dealingwith the somewhat salty water present inthese streams. This does not appear to bethe case, however, since Shortcut Canal,which did substantially better than theothers in terms of biology, fecal coliforms,

and some nutrient levels, had aconductivity of 1910 Τmhos/cm. Thismeasurement is equal to that of BlackSweetwater Creek, the most degraded siteof all those sampled in this survey.

Undoubtedly, the main ecological problemwith these streams has to do withagriculture. All four streams have beenaltered, channelized to function asdrainage ditches for the agriculturaloperations prevalent in this area. In mostcases, environmentally beneficial landmanage-ment practices are not utilized bythose farming in Black Hammock. Waterladen with nutrients and probablypesticides flows into these ditches, which inturn flow due north into Lake Jesup. Insome places, animal pens are at the veryedge of the steeply cut banks of thesecanals, no doubt contributing greatly to thefecal coliform concentrations. In BlackSweetwater Creek, where one of thesepens apparently had a drainage pipeflowing into the stream, the fecal coliformlevel was 1,300 colonies 100mL, a definiteviolation of state water quality standards.

We believe that the Black Hammock area isan ideal candidate for an EcosystemManagement effort. Farmers in the areacould be educated about current problemsand offered suggestions for moreenvironmentally sound and hopefullyfinancially feasible alternative methods.The establishment of better landmanagement practices in the area shouldhelp to improve the water quality in boththese streams and Lake Jesupdownstream.

Palm farm alongside Black Sweetwater Creek

32

Sanford area streams

Unlike the two groups already discussed,the streams in the Sanford area which wereincluded in this study are very different fromone another. Elder Springs Run is a naturalstream fed by a number of small headwatersprings and wetlands. Although canalizedin some areas, its course is relativelynatural. The majority of the land use in thebasin is urban. The Sanford Airport ditch,on the other hand, is not a natural stream,but a drainage canal which conducts thecollective flow of several ditches in theairport vicinity south, entering Lake Jesupat the mouth of Phelps Creek, which flowsfrom west to east. Despite thesedifferences, however, the two streamsperformed similarly in this study.

Both streams received a “good” rating onthe Stream Condition Index.Macroinvertebrate species were numerous,with a fairly good number of pollution-sensitive taxa present. The dominantmacroinvertebrate species present in bothstreams was the same seen in the WinterSprings area, Microcylloepus pusillus, theriffle beetle. Of the two streams, ElderSprings Run did somewhat better in termsof biology than the drainage ditch. Thismight have been a result of the availablehabitat, which was considerably better inthe more natural Elder Springs Run than inthe man-made Airport Ditch.

In terms of water chemistry, the AirportDitch actually had somewhat better waterquality than Elder Springs Run. Mostnutrient measurements were roughly in the50th to 70th percentile range in ElderSprings Run, compared with the 20th to50th percentile range for Airport Ditch. Thewater was much more highly colored inElder Springs Run than in the ditch. ElderSprings Run’s water was the darkest of anyseen in this survey (400 CUs; equal tomeasurements from Salt Creek nearOviedo). The water from Airport Ditch wasamong the least colored. Fecal coliforms

were relatively high at both sites, thoughnot in excess of standards.

Generalization of land use effects on waterquality in these two side-by-side basins isdifficult, since one is dominated byresidential development and the other bycommercial (airport) development. Roughlyspeaking, however, the remaining land usepercentages (natural lands, rangeland, andagriculture) are basically equal between thetwo. Due to the similarity of the results,then, it can be observed that thedominating urban and commercial landuses in these specific basins have hadapproximately the same effect on waterquality.

Suggestions for maintenance orimprovement in water quality in this areainclude the establishment of adequatestormwater retention systems asdevelopment in the area increases and theuse of best management practices by areagrowers and ranchers.

Airport Ditch at Marquette Road, looking upstreamtoward Sanford Airport

33

Summary

The quality of water entering Lake Jesupvia the tributaries monitored in this studyvaried from area to area and, to a lesserdegree, from stream to stream. However, afew overall observations can be made.

Fecal coliform bacteria levels were high inall of these streams. The lowest countseen, 170 colonies per 100mL, wasrecorded at Gee Creek. Measured coliformlevels in 70% of Florida’s streams werelower than this. The highest fecal countencountered in this study, at BlackSweetwater Creek, was 1,300colonies/100mL, in the 99th+ percentile.Possible sources of such contaminationinclude runoff from pasturelands orlivestock holding areas, faulty orinsufficiently spaced septic tanks, andrunoff from urban areas.

Generally speaking, nutrient levels tendedto be high in these streams. There wereexceptions, however, particularly in regardto total Kjeldahl nitrogen. In the majority ofthese streams, TKN was in the 50thpercentile or less. For most other nutrientparameters, however, measurements werefairly high. Nutrient enrichment might occuras a result of urban nonpoint source runoff,agricultural fertilizer runoff, and landmanagement practices that do not place apriority on ecosystem health. It is notdifficult to find examples of these situationsthroughout the study area.

Although nonpoint source pollution fromurbanized areas is a contributing factor towater quality problems in the area, theseresults suggest that the most significantcontributor to poor water quality in LakeJesup’s tributaries is agriculture. Reversingthese poor water quality trends wouldrequire education, cooperation, and theimplementation of land use practices thatmake both economic and ecological sense.Accomplishing these goals would not besimple, but, along with restoration efforts,would be an important step in helping toimprove the water quality of Lake Jesup.

References

Barbour, M.T., J. Gerritsen, and S.J. White.1996. Development of the StreamCondition Index for Florida. Prepared forthe Florida Department of EnvironmentalProtection, 105 pp.

Brigham, W.U. 1982. Aquatic Coleoptera.In Brigham, A.R., W.U. Brigham, and A.Gnilka, eds. Aquatic insects andoligochaetes of North and South Carolina.Midwest Aquatic Enterprises, Mahomet, IL,837 pp.

Brown, H.P. 1972. Aquatic dryopoidbeetles (Coleoptera) of the United States.Biota of Freshwater Systems, IdentificationManual #6. U.S. Environmental ProtectionAgency, 83 pp.

Florida Department of EnvironmentalProtection. 1996. Standard operatingprocedures for biological assessment.FDEP Biology Section, unpaginated.

Marzolf, E.R. 1997. Draft document. LakeJesup watershed surface watermanagement plan. St. Johns River WaterManagement District, Palatka, FL, 205 pp.

Thompson, F.G. 1968. The aquatic snailsof the family Hydrobiidae of peninsularFlorida. University of Florida Press,Gainesville, 268 pp.

Clifton Springs Run at Lake Jesup

For further information, contact Dana R. Denson, Surface Water Monitoring Section, FDEP, at (407) 894-7555, 3319 Maguire Blvd., Orlando 32803, e-mail: [email protected].

34

AppendixAssessment Data - Lake Jesup Tributaries Report

Page One

site name STORET # date SCI rating # taxa FL Ind. EPT dominant taxon habitat color alkalinityof possible 145 CU mg/L CaCO3

Airport Ditch 20010187 8/25/97 21 good 22 5 4 Microcylloepus pusillus 86 60 51.3Bear Creek 20010049 9/24/97 29 v. good 27 11 5 Microcylloepus pusillus 131 100 56Black Swtwtr 20010354 9/24/97 15 poor 19 6 1 Pyrgophorus platyrachis 65 40 132Elder Springs 20010294 8/25/97 25 good 24 9 3 Microcylloepus pusillus 121 400 61.5Gee Creek 20010185 3/3/97 27 v. good 28 13 3 Polypedilum convictum 111 40 93.5Howell/434 20010186 7/9/96 23 good 19 10 2 Pisidiidae (then M. pusillus) 117 80 42Howell/WSB 20010042 8/18/97 27 v. good 21 11 7 Microcylloepus pusillus 102 75 45Salt Creek 20010051 8/12/97 17 poor 19 5 2 Pyrgophorus platyrachis 114 400 91.8Shortcut Cnl 20010127 9/8/97 25 good 21 11 4 Gammarus sp. 87 40 127Soldier Creek 20010184 7/9/96 25 good 24 7 3 Microcylloepus pusillus 131 200 53Sweetwater 20010090 8/12/97 21 good 15 8 0 Pyrgophorus platyrachis 76 100 110

site name stream width depth Secchi DO conduct. temp. pH canopy cover riparian width velocity turbiditym m m mg/L umhos/cm deg. C SU light, moderate, or heavy m * m/s ** NTU

Airport Ditch 3.0 0.4 >0.4 6.72 190 26.37 6.97 moderate 0.3 0.07 2.4Bear Creek 5.5 1.0 0.5 6.60 230 25.40 7.16 moderate 12 0.50 9.6Black Swtwtr 3.0 0.2 >0.2 1.89 1910 24.48 6.99 moderate 5 0.06 1.9Elder Springs 3.0 1.5 1.0 6.45 292 25.27 6.95 moderate 8 0.33 4.2Gee Creek 2.5 0.4 >0.4 6.11 277 21.93 8.25 light 10 0.15 2.1Howell/434 4.0 1.5 1.0 5.60 162 27.60 7.00 moderate >18 0.30 5.8Howell/WSB 5.0 0.5 0.4 6.02 173 29.00 6.90 moderate 2 0.50 8.8Salt Creek 4.0 0.8 0.5 5.31 3000 24.20 6.88 heavy >18 0.17 10.0Shortcut Cnl 3.5 0.2 >0.2 4.68 1910 22.30 7.24 light 3 0.33 5.7Soldier Creek 3.0 1.0 >1.0 6.10 163 25.70 6.97 heavy >18 0.30 3.8Sweetwater 2.5 0.4 >0.4 5.99 709 24.55 7.19 moderate 0 0.50 2.1

* Because a riparian zone width of greater than 18 meters is considered ideal, no further estimation is made when widths exceed 18 m.

** Fastest velocity of three measurements made at representative cross-section.

35

AppendixAssessment Data - Lake Jesup Tributaries Report

Page Two

site name fecals total P chlorides sulfates NH3+NH4 unionized NH3#/ 100 mL percentile mg/L percentile mg/L percentile mg/L percentile mg/L percentile mg/L percentile

Airport Ditch 710 94 0.03 20 20 40 9.8 40 0.04 50 0.0002 50Bear Creek 540 91 0.14 60 21 42 9.9 40 0.05 60 0.0005 70Black Swtwtr 1300 99+ 0.35 85 520 95+ 78 87 0.11 5 0.0007 75Elder Springs 510 90 0.15 80 49 62 15 50 0.05 60 0.0003 60Gee Creek 170 70 0.14 70 23 44 9.8 40 0.05 60 0.0045 95Howell/434 320 84 0.11 60 15 32 10 40 0.04 50 0.0003 60Howell/WSB 320 84 0.07 50 18 37 12 45 0.03 40 0.0002 50Salt Creek 470 90 0.35 85 810 95+ 150 95+ 0.29 40 0.0014 90Shortcut Cnl 420 88 0.30 85 580 95+ 87 90 0.13 10 0.0013 85Soldier Creek 620 93 0.21 80 14 30 4 33 0.06 65 0.0003 60Sweetwater 740 95 0.42 90 120 78 45 74 0.19 20 0.0019 90

site name TKN NO2+NO3 land use percentages *** USGS gagemg/L percentile mg/L percentile natural silviculture pasture agriculture residential commercial industrial

Airport Ditch 0.49 20 0.03 25 21 0 18 0 29 30 2 noBear Creek 0.81 40 0.15 60 29 0 4 21 46 0 0 noBlack Swtwtr 0.47 20 0.06 45 60 0 1 23 11 5 0 noElder Springs 1.30 70 0.07 45 32 0 1 15 50 2 0 noGee Creek 0.46 20 0.20 70 29 0 1 3 65 0 2 yesHowell/434 0.67 30 0.11 60 25 0 1 4 68 0 2 yesHowell/WSB 1.00 50 0.11 60 25 0 1 4 68 0 2 yesSalt Creek 2.90 95 0.16 65 75 0 2 8 15 0 0 noShortcut Cnl 0.52 25 0.11 60 0 20 5 38 5 0 0 noSoldier Creek 0.82 40 0.13 60 30 0 2 7 57 0 4 yesSweetwater 1.40 75 0.75 90 16 0 16 18 40 10 0 no

[Note: Percentile values given are rankings compared to other Florida streams, as shown in the draft document "Typical Water Quality Values forFlorida Streams, Blackwater, Springs, Lakes, and Estuaries" being prepared by Joe Hand et al. of FDEP, Tallahassee.]

*** Land use percentages are for entire stream watershed, and are based on St. Johns River Water Management DistrictGIS land use coverages.

Documents

Biological and Chemical Assessment of Water Quality in ... · Orlando and other inland areas. Soon, however, farmers began to clear the rich muck lands south of the lake to plant