Comparison of median concentrations 1991-2003

2003 Lake Water Quality Report

Comparison of median concentrations for chemical data in City of Orlando lakes from 1991-2003.

Parameter	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003

pH	7.76	7.63	7.40	7.47	7.48	7.85	7.62	7.30	7.72	7.96	7.83	7.83	7.79

Alkalinity (mg/l as CaCO3)	52.0	51.0	48.0	43.0	44.0	40.0	43.0	44.0	44.0	46.3	43.3	44.1	45.2

Total Phosphorus (mg/l)	0.040	0.042	0.048	0.045	0.043	0.039	0.040	0.036	0.033	0.034	0.034	0.034	0.034

Ortho Phosphorus (mg/l)	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.004	<0.004	<0.004	<0.004

Total Nitrogen (mg/l)	0.81	0.85	0.86	0.82	0.80	0.76	0.75	0.70	0.76	0.78	0.78	0.75	0.82

Ammonia (mg/l)	<0.03	<0.03	<0.03	<0.03	<0.03	<0.03	<0.03	0.03	0.04	<0.03	<0.02	<0.02	<0.02

Nitrate Nitrogen (mg/l)	<0.02	<0.02	<0.02	<0.02	<0.02	<0.02	<0.02	<0.02	<0.02	<0.02	<0.02	<0.02	<0.02

Nitrite Nitrogen (mg/l)	<0.020	<0.020	<0.020	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005	<0.005

Total Kjeldahal Nitrogen (mg/l)	0.82	0.84	0.82	0.78	0.76	0.74	0.74	0.60	0.74	0.76	0.77	0.79	0.80

Total Suspended Solids (mg/l)	5.7	6.0	6.0	7.0	6.5	6.5	6.0	5.0	5.5	5.0	4.5	3.5	4.0

Volatile Suspended Solids (mg/l)	4.5	5.0	5.0	6.0	6.0	5.0	4.0	4.0	5.0	4.5	4.0	3.8	4.0

Total Dissolved Solids (mg/l)	125	126	124	117	116	116	108	112	126	132	128	128	124

Chlorophyll-a (mg/m³)	18.0	14.2	21.0	17.0	18.4	17.0	18.0	17.3	16.8	14.8	14.6	11.4	11.1

Conductivity (umhos @ 25°C)	207	202	198	195	182	177	177	170	177	182	192	196	184

Secchi Depth (m)	1.1	1.0	1.1	1.1	1.1	1.1	1.1	1.1	1.1	1.1	1.0	1.0	1.2