Can LOADEST be used for TMDLs?
• Perhaps. Dan Hippe writes: “Consider, that often loads computational work that the USGS does and the load allocations done for a TMDL are NOT procedurally similar and therefore may not be easily reconciled. Loads estimation in the USGS generally involves estimating export of a mass of material per unit of time at a limited number of instruments sites within river networks. What many TMDL’s are doing is assigning an average or hypothetical loading rate to all activities in a watershed and accumulating (or routing them) them within the stream network, with rather few observations or verification based on instream data. If done right, the work we do at a limited number of points should be a verification of how well the loadings are assigned and accumulated or routed through the network as part of a TMDL — however, that presumes they are looking at actual conditions and not a hypothetical average condition. In most simplistic TMDL studies: Point source discharges are generally assigned a
