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Visual Observations on June 1, 2017 On June 1, 2017, a visual observation of the canal Study Area by Stormwater Division personnel indicated (1) thick duckweed at the westernmost section; (2) scattered duckweed, water lettuce, algae, and miscellaneous grasses throughout most of the rest of the canal; (3) thick growth of vegetation in the canal just west of 82nd Avenue; and (4) thick eel grass growing on the canal bottom west of 74th Avenue. A significant flow of artesian water was entering the canal from a ranchette residence located north of the canal about 400 feet east of Sample Point A. The discharge appears to be artesian well water overflow from a pond(s) on the property. Staff observed a significant flow of water in the canal from west to east, discharging into the Lateral C Canal at 74th Avenue. Most of the water in the canal appeared to be artesian water as it was clear and had a slight milky appearance, indicative of an artesian source. Water in the canal flows from west to east and the ranchette pipe discharge was the largest observed contributor of flow in the canal. Staff also noted several suspected seepage points along the southern canal bank abutting the West Regional Wastewater Treatment Facility (WRWWTF) wetland system. The seepage points were slightly above the canal water surface and appeared to contain white sulfur bacteria. Small but constant flows were observed discharging into the canal at each location. Visual Observation Summary • Noticeable seepage points along the canal bank adjacent to the WRWWTF wetland system implies some seepage into the canal may be occurring or possibly groundwater intrusion. Sulfur bacteria appears to be growing at the seepage points. • The lush vegetation in the canal immediately west of 82nd Avenue indicates nutrients are present in the canal water. • The flow of water is to the east into the Lateral C Canal at 74th Avenue. • There appears to be a significant artesian well water input into the canal and a significant source of this water is from a ranchette west of Sample Point B. Laboratory Results for Nitrogen Certain forms of nitrogen in water can contribute to algae blooms in the Lagoon. Total nitrogen is the sum of total Kjeldahl nitrogen (TKN) and nitrite/nitrate nitrogen or NOx. TKN is the sum of organically bound nitrogen (such as amino acids or complex organic molecules containing nitrogen) and ammonia nitrogen. i.e. TKN = total organic nitrogen + ammonia nitrogen. Ammonia and NOx are the forms available for direct uptake by plants.. In order for organic nitrogen to become biologically available, it must be acted upon by enzymes such as deaminase, or certain environmental factors that strip amine groups from the organic complex. If the organic nitrogen molecules are anthropogenic in origin, such as associated with synthetically created organic compounds, then plant access to the nitrogen may be even more difficult. Because Total Nitrogen is the sum of NOx and TKN, its discussion is meaningless with respect to this analysis. 4 FAPublic WorksWeithM\Stormwater Projects\IRFWCD 8th Street Canal Water Study\Memo 2 - 8th Street Canal.doc 35