Rocky River Monitoring Study, Division of Water Resources- Water Sciences Intensive Survey Branch

Transcription

1 Rocky River Monitoring Study, 2016 Division of Water Resources- Water Sciences Intensive Survey Branch

2 Thank You Tim Sweeny Town of Siler City

3 Area of Study 6.7 mile stretch of River located in Chatham County, near Siler City. Contains Charles Turner Reservoir, Hackney Dam, and the Loves creek discharge for Siler City WWTP. Currently listed on the EPA 303d list for low reoccurring D.O. at US 64 Gauging station.

4 Study Design 8 sites sampled for physical and chemical parameters USGS gauging station at US 64 Flow data collected at CPFRR01 & CPFRR02 Deployed multiparameter sondes at CPFRR01 & CPFRR03 Pulse event (7/8) captured by sondes and flow meters.

5 Parameters Collected Physical Chemical Temperature ( C) Dissolved oxygen (mg/l, % saturation) ph (s.u.) Specific Conductivity (µs/cm) Nutrients (mg/l) NH 3 NO 2 + NO 3 TKN / DKN TP / DP Total Organic Carbon (mg/l) 5 Day Biological Oxygen demand (mg/l) Chlorophyll a (µg/l) Turbidity (NTU) Solids (mg/l) Hardness (mg/l)

6 Results

7 Charles Turner Reservoir Flow over the dam at Charles Turner Reservoir, May 26 th Documented algal bloom near CPFTR01 on July 14 th

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9 Upstream Down Charles Turner Reservoir Surface physical results remained within state standards during the course of the study. CPFTR05 CPFTR03 CPFTR01 Temperature ( C) D.O. (mg/l) Elevated Dissolved oxygen and ph observed at all sites at surface. Low Dissolved Oxygen at depths > 1.5 m ph (s.u.) * Sp. Cond (µs/cm) Range of physical values May to July 2016

10 Charles Turner Reservoir Total nitrogen and phosphorus remained consistent in the Charles Turner Reservoir. Upstream Down CPFTR05 CPFTR03 CPFTR01 TN mg/l mg/l mg/l TP mg/l mg/l mg/l Chlorophyll a showed an increasing trend downstream TOC remained elevated chlorophyll a µg/l µg/l µg/l TOC mg/l mg/l mg/l Range of Nutrient, chlorophyll a, and TOC values observed from May to July 2016

11 Rocky River Downstream of Charles Turner Reservoir CPFRR01 looking Downstream CPFRR02 from the bridge at Snowcamp rd.

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13 Rocky River Downstream of Charles Turner Reservoir Instantaneous surface readings remained above state standards during the study period at both sites Lower ph then that observed in Charles Turner Reservoir Upstream Down CPFRR01 CPFRR02 Temperature ( C) D.O. (mg/l) ph (s.u.) Sp. Cond (µs/cm) Range of physical values May to July 2016

14 Rocky River Downstream of Charles Turner Reservoir Lower total nitrogen and phosphorous observed immediately downstream of Charles Turner Reservoir at site CPFRR01, and at CPFRR02 Single chlorophyll a exceedance observed at CPFRR01 on June 6 th Similar TOC values observed as those in Charles Turner Reservoir Upstream Down CPFRR01 CPFRR02 TN mg/l mg/l TP mg/l mg/l chlorophyll a µg/l µg/l TOC mg/l mg/l Range of Nutrient, Chlorophyll a, and TOC values observed from May to July 2016

15 Hackney Reservoir Sluice gate at the bottom of Hackney Dam, taken June 13 th Hackney Reservoir near site CPFRR03 looking downstream July 7 th

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17 Hackney Reservoir Dissolved Oxygen remained above state standards at surface, low D.O. observed near bottom at CPFRR04 ph value of 8.95 at Site CPFRR04 is at upper limit of state standards for class C waters. Upstream CPFRR03 Down CPFRR04 Surface CPFRR04 Bottom Temperature ( C) D.O. (mg/l) ph (s.u.) * Sp. Cond (µs/cm) Range of physical values May to July 2016

18 Hackney Reservoir CPFRR03 CPFRR04 Elevated total nitrogen and phosphorous Exceedances of state standards for chlorophyll a at CPFRR04, none at CPFRR03 TN mg/l mg/l TP mg/l mg/l chlorophyll a µg/l µg/l TOC mg/l 9-10 mg/l Range of Nutrient, Chlorophyll a, and TOC values observed from May to July 2016

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20 Downstream of Hackney Dam Upstream US64 Gage Down CPFRR05 Exceedances of state standards for dissolved oxygen at both sites during the study Temperature ( C) D.O. (mg/l) Exceedance of state standard for ph observed on July 7 th at CPFRR05 ph (s.u.) Sp. Cond (µs/cm) Range of physical values May to July 2016

21 Downstream of Hackney Dam Chemical parameters were only collected at CPFRR05 during this study TN TP CPFRR mg/l m/l Collected Downstream of Loves Creek chlorophyll a µg/l Elevated Total Nitrogen in comparison to the rest of the river in the area of study TOC mg/l Range of Nutrient, Chlorophyll a, and TOC values observed from May to July 2016

22 Pulse Event Released as part of the 401 certification from Charles Turner Reservoir. Measured 26.9 cfs at CPFRR01 immediately downstream of dam and 25.1 cfs at CPFRR02

23 CPFRR03 looking downstream on 7/7

24 CPFRR01 looking upstream during the pulse.

25 Deployed Data Pulse event occurred on July 8 th RR03 Rapid Rise in stage at CPFRR01, delayed and gradual rise at CPFRR03 Slight increase in stage at US 64 gauging station US 64 Gauge RR01

26 RR03 US 64 Gauge RR01

27 RR03, looking downstream 7/7 RR01, 7/8 during pulse

28 RR01 D.O. RR03 stage RR03 D.O. RR01 stage

29 US 64 D.O. US 64 Stage RR01 Stage

30 Stage at CPFRR03 on July 7th

31 Hackney Reservoir on July 14 th 1 week after the pulse.

32 Algal bloom at Charles Turner Reservoir July 8 th Bloom Conditions

33 Mid-reservoir in Hackney July 14th

34 Range of D.O. at various sites in the area of study Charles Turner Reservoir Oxygenated epilimnion CPFTR01 ( mg/l) CPFRR01 ( mg/l) CPFR02 ( mg/l) Hackney Reservoir Hypoxic hypolimnion CPFTR01 ( m CPFRR03 ( mg/l) CPFRR04 ( mg/l) CPFRR05 ( mg/L) 1 m ( mg/l) bottom ( mg/l) US 64 gauging station ( mg/l)

35 Joseph Smith Division of Water Resources- Water Sciences Intensive Survey Branch

36 Stage Plate at Snowcamp road during pulse, plate starts at 3.6 ft