tmdl: Calculates TMDL
In tmdl: Flow and Load Duration Curve plots for TMDL

Description Usage Arguments Details Value Examples

View source: R/tmdl.R

Calculates TMDL

1 2	tmdl(data, names = list(), mult = 2.446576, WQS = 0.1, target = WQS, WLA = NA, MOS = TRUE, intervals = fi, interp = "spline")

`data`	Typically result of `rankflow`, a `data.frame` with columns "Q" & "exc". Those can be overriden using `names`
`names`	List that can specify custom column names in data frame `data` for `Q` and `exc`
`mult`	Multiplier to convert flow rate times pollutant concentration to resulting load units. If flow rate is given in cfs and pollutant concentration in ppm, default `mult` yields load in kg/day
`WQS`	Water quality standard
`target`	Same as `WQS`. Has precedence over `WQS`.
`WLA`	Wate Load Allocation
`MOS`	Margin Of Safety. FALSE for implicit, 0-1 to use % of Load Capacity, or TRUE to calculate MOS for flow interval as a difference between LC for median and low flows for a given flow interval
`intervals`	Currently broken
`interp`	How to interpolate WLA for different exceedance level. Used in plotting.

WLA can be one of the following

numeric length of 1 or 5
matrix of data.frame with 5 columns
list of functions

Object of class "tmdl", essentially a list with the following components...

data(flow)
data(pol)
flow.ranked <- rankflow(flow,pol,names=list(date="Date",Q="cfs"))
fd.fig <- fdplot(flow.ranked,names=list(Q="cfs"),values=TRUE)
WQS <- 5 # mg/L => 10 NTU
WLA.construction = function(exc,LC,MOS,LC.fun,MOS.fun) {
  LA = ifelse(exc>75, LC.fun(75)-MOS.fun(75), LC - MOS)
  .01 * LA
}
MS4.Duluth = function(exc,LC,MOS,LC.fun,MOS.fun) {
  .16 * (LC-MOS-WLA.construction(exc,LC,MOS,LC.fun,MOS.fun))
}
WLA=list(WLA=WLA.construction, MS4=MS4.Duluth)
kr.tmdl <- tmdl(flow.ranked,names=list(Q="cfs",pol="TSS"),WQS=WQS, WLA=WLA)
summary(kr.tmdl)