Mississippi River near Lock & Dam 4 (Agency codes: M752.8Y and M752.8Z) 

Descriptive Statistics of Concentration Data (Milligrams/Liter)
Statistics are based on mean concentrations of the combined sites
See background information of this site for details

                  TN_N     NOx_N     NHx_N      TP_P     SRP_P       TSS        Cl   SiO2_Si
Total obs. =       115       119       119       109       119       117       119       119
Start date =  04/30/93  04/30/93  04/30/93  04/30/93  04/30/93  04/30/93  04/30/93  04/30/93
End date   =  06/02/98  06/18/98  06/18/98  06/02/98  06/18/98  06/18/98  06/18/98  06/18/98
Mx smp int days=    44        44        44        57        44        44        44        44
Mean samp int=    16.3      15.9      15.9      17.2      15.9      16.2      15.9      15.9
Stdv samp int=     5.8       5.4       5.4       8.1       5.4       5.6       5.4       5.4
Mean conc. =      2.43      1.94     0.098     0.126     0.052      11.9      15.4      5.78
Stdev conc.=      0.75      2.63     0.095     0.050     0.044       6.9       4.3      1.67
Min conc.  =      0.92      0.30     0.001     0.023     0.001       1.0       7.8      1.44
25% conc.  =      1.86      1.19     0.033     0.084     0.024       6.7      12.6      4.90
Med. conc. =      2.41      1.73     0.063     0.116     0.039      11.7      14.5      6.06
75% conc.  =      2.84      2.14     0.139     0.161     0.070      16.8      18.1      6.93
Max conc.  =      4.55     29.24     0.445     0.263     0.245      33.3      29.6      9.16

Flow summaries are in the LOADEST2 diagnostic information

TN_N    = Total Nitrogen (as N)
NOx_N   = Total Nitrate + Nitrite (as N)
NHx_N   = Dissolved Ammonia (as N)
TP_P    = Total Phosphorus (as P)
SRP_P   = Soluble Reactive Phosphorus (as P)
TSS     = Total Suspended Solids
Cl      = Dissolved Chloride (as Cl)
SiO2_Si = Dissolved Silicon (as Si)