RainfallNZ
commented
4 years ago This is the imperfect solution that I have ended up using:
1/ I start with the "WaterQualityStationLoadConcData.xlsx" to get the measured export coefficient data.
2/ I convert this to a load using the CATCHAREA in the file
3/ I then update the loads with any in the "July2020_loads_at_locationswithnotablydifferentnzsegment.xlsx" file
Next thing is to get the mean flow for each site. Start with the original files flows. If the site has had a location change, use the flows from REC2MeanFlow, Update the Waiau sites using the "corrected" Waiau flows.
The water quality values for the Waiau are wrong.
See email from Ton to both Tims on 22nd July at 12:56 pm, and at 17:38 with subject "RE: Southland water quality stations" loads for Tuatapere should be:
TN = 2116.7 t/y
TP = 125.6 t/y mean flow is 138.852 m3/s
And loads at Sunnyside of:
TN = 800.5 t/y
TP = 45.0 t/y mean flow of 90.446 m3/s .
This is problematic. The water quality site load data is output of a script from Ton. If I manually edit it, then the edits will be lost next time Ton updates it. Currently the flow estimates are taken from the REC mean flow data file with an overide for the Waiau below the Manapouri lake outlet to maintain hydrological balance assuming the mainstem has little gain or losses. If I change the mean flow of the two water quality sites, then they will be out of kilter with my estimated values. However it is better to have measured data than estimated. But then there are other incorrect data n the water quality load data. Best solution: Get Ton to update the load spreadsheet to align with the checked locations, and update the mean flows as well, and manually edit the waiau flows, and remove the confidence interval data. Then use it, including its mean flows. In the interim, hardcode in the Waiau flows.