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Golden Alga ( Prymnesium parvum ) Salt River Lakes . Marc Dahlberg Water Quality Program Manager March 8, 2011. Golden Alga. Temperature range between 5 and 30 degrees Celsius Blooms occur when nutrients are readily available. When nutrients become depleted toxins are released.
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Golden Alga (Prymnesium parvum) Salt River Lakes Marc Dahlberg Water Quality Program Manager March 8, 2011
Golden Alga Temperature range between 5 and 30 degrees Celsius Blooms occur when nutrients are readily available. When nutrients become depleted toxins are released. The potency of the Golden alga is nearly five times greater at a pH 8.5 than it is at 6.5. Cells are very fragile and are easily ruptured Prefers a saline environment – does very well in waters with conductivities over 2000 µmhos/cm
Diagnostic Features • 8 – 11 microns long • 3 – 6 microns wide • Nucleus is located centrally between two chloroplasts • 2 equal flagella and a well developed heptonema
Average Conductivity Salt River Lakes (Saguaro-Canyon-Apache) and Salt River below Saguaro
Dead or Dry Roosevelt Lake - 1928, 1929, 1930, 1931, 1934, 1938, 1940, 1947, 1950, 1951, 1956 San Carlos Lake – 1934, 1938, 1939, 1940, 1946, 1947, 1948, 1950, 1951, 1952, 1953, 1955, 1956, 1957, 1960, 1961, 1965, 1971, 1976, 1977 Bill Silvey
Average Conductivity Salt River Lakes (Saguaro-Canyon-Apache) and Roosevelt Lake
Roosevelt LakeSeptember 15, 2000 Conductivity 1392 1801 2125
Golden Alga Caused Fish Kills in Waters without Forest Fires Lake Conductivity Kearney Lake Water Ranch Lake Las Vegas 2500 – 8500 2700 – 2900 2500 - 2900
Waters with Forest Fires that Have Not Resulted in a Golden Alga Fish Kill Lake Conductivity Horseshoe Bartlett Black Canyon Lake 400 – 750 400 – 700 50 -225
July 2002 July 19, 2002 Conductivity 2570 Flow 263 July 31, 2002 Conductivity 753 Flow 900
Questions? September 14, 2011 Conductivity 1814 Flow 288 CFS Roosevelt 1091 1.185 million AF Apache 1067 Canyon 1045 Saguaro 1062
Salt River Lakes – Drainage Area Roosevelt – 5830 square miles Apache – 5842 square miles (12 sq mi) Canyon – 6101 square miles (259 sq mi) Saguaro – 6330 square miles (229 sq mi) 92% of the watershed lies above Roosevelt dam
Salt River Lakes - Storage Roosevelt – 1,653,043 acre feet (81%) Apache – 245,138 acre feet (12%) Canyon Lake – 57,832 acre feet (3%) Saguaro – 73,613 acre feet (4%) Total – 2,029,646 acre feet
Conductivity The specific conductance test measures the ability of water to pass an electrical current. Conductivity in water is affected by the presence of inorganic dissolved solids such as chloride, sulfate, sodium, calcium and others. The greater the concentrations of ions, the larger the conductivity.