The State of the Severn River 2018
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The State of the Severn River 2018 ITS ALL ABOUT THE TRIBLETS Andrew C. Muller, Ph.D. Diana L. Muller, M.S. Associate Professor Executive Director Oceanography Department Maritimas United States Naval Academy Annapolis, MD. Severn River Association Severn RIVERKEEPER Dr. Muller, Professor of Oceanography, USNA Diana Muller, Executive Director, Maritimas Keith Underwood for his boat Mark Lister for his field work and boat John Page Williams- Chesapeake Bay Foundation And all of the volunteers Methodology Weekly from July to end of October the Severn River Partnership performed vertical water quality monitoring in the tidal estuary using a YSI Pro multi-meter for dissolved oxygen, pH, temperature, salinity, and water samples for bacteria. Dr. Andrew Muller and Capt. Diana Muller trained the Severn River Partnership volunteers by strict QA/QC guidelines as per EPA Chesapeake Bay program methodology and the Maryland Tributary Assessment Coalition (EcoCheck, 2011). The statistical analysis was performed by Dr. Muller and Capt. Muller by MTAC protocols and standard statistical analysis. Statistical analysis was performed using Sigma Plot 12. ArcGIS Pro was utilized to process Landsat 8 and 5 LIDAR data, Google Earth Pro was used to display urban and shoreline changes over time (USGS, 2018) (Globe, 2018). Nutrient data was provided by the Maryland Department of Natural Resources. Water Quality Grades Water Clarity 80% Dissolved Oxygen 62% Bacteria 82% Total Nitrogen 17% Total Phosphorus 50% Dissolved Oxygen The healthy level for dissolved oxygen is 5 mg/L or greater for the Severn River Severe hypoxia occurs at < 2 mg/L and anoxic conditions are when oxygen is below 0.2 mg/L. The Story of Dissolved Oxygen Normoxic defined as 5 mgl-1 or above Winchester Lump D.O. Sub-normoxic < 5mgl-1 > 2mgl- 5 1 ) hypoxia < 2 mgl-1 > 0.2 mgl-1 -1 4 Anoxic < 0.2 mgl-1 3 ** Longest continuous period of anoxia: 85.35 hours or 3.5 2 days! 1 Anoxic conditions for a total of 155.97 hours or 43.62% of the 0 total length of record (mgl oxygen Dissolved 35% Hypoxic 0 100 200 300 400 Hours after 6/27/18-13:50 Hypoxic Squeezing Lower Western Shore • Hypoxic squeeze index ( HSI) 5 Δ퐷표 퐻푆퐼 = depth avg. Do 4 3 In order to fully understand water HSI 2 column conditions in relation to healthy habitats 1 Maritimas has developed a hypoxic squeeze index 0 0 20 40 60 80 100 Percentage of water column below 2 mg/L R 2 = 0.76 Percent below 2 mg.L vs HSI P=.03 Plot 1 Regr Median squeezing = 1.4 Translates to median value of 16 % of water column below 2 mg/L Asquith Creek A unique triblet and why one size does not fit all ASQ creek July, 2016 ASQ Aug 1 0 0 -1 -1 -2 -2 Depth m Depth -3 -3 Depth (m) Depth -4 -4 Mean =4.85 Median- 0.71 -5 HSI = 2.95 -5 0 2 4 6 8 10 0 2 4 6 8 10 12 14 16 DO mg/l Col 2 vs Col 1 D.O. mg/L Severn River Hypoxic Squeezing 3.5 3.0 2.5 2.0 HSI 1.5 1.0 SR5 0.5 WMS CHS SLT SR7 SRO BRW ASQ 0.0 Station Hypoxic Squeeze Index and Air Temperature Water Clarity Median 0.8m +/- 0.28m n= 117 MTAC score = 80% Total Nitrogen 17 % passing Septic Systems on the Severn River Watershed Total Phosphorus 50% Bacteria (Enterococci) 82% passing for 2018 The hectare is an SI accepted metric system unit of area equal to 100 acres (10,000 m²) and primarily used in the measurement of land. An acre is about 0.4047 hectare and one hectare contains about 2.47 acres. SAV index and ENSO Severn River Does Climate 3 influence SAV? 2 1 0 -1 SAV/ONI index SAV/ONI -2 -3 1980 1985 1990 1995 2000 2005 2010 2015 2020 Year ONI SAV INDEX Monthly Surface Temperature WT 7.1 Median 25.7 C, 78.3 F Hottest temperature ; 31 C, 81.8F MD MDR eyes on the bay pH WT 7.1 MD DNR eyes on the bay Rain, Rain and More Rain!! The climatic conditions were heavy rain events; July 17, 2018, 3.35 inches, July 21, 2018, 4.79 inches, July 24, 2018, 4.07 inches, September 9, 2018, 2.23 inches, and September 18, 2018, 2.22 inches. Overall there were 130 rain events with over 63 inches of rain. These heavy rain events dropped the salinity of the Severn River triblet to a median vertical profile of 4.46 PSU (practical salinity units) (n=1182), the healthy range for the salinity of this triblet is 10PSU. Conclusions • It is important to understand the complete system when attempting to make important policy decisions regarding restoration. • Physics dominates and controls the system, no coriolis and no sloshing of water in and out by tides, • Hypoxia and anoxia are locally controlled (it’s the creeks!!!) • Susquehanna River is NOT the main polluter to LWS Rivers. • All water quality parameters are cyclical. Annual scorecards don’t tell the full story. • Temperature is critically important, as the system appears to be responding to inter-annual variations. • CDOM and Obs are potential ways to track restoration effectiveness • HSI and WDI are promising metrics • Need more studies on restoration effectiveness, including BAAs, long-term studies and downstream measurements mainly tidal. • Rehabilitation for Ecological Resilience not Engineering Resilience Thank You Andrew Muller, Ph.D & Diana Muller, M.S https://maritimasusa.org/.