Hi Manoah, I agree with José Luis: without a bathymetry of 1988 and 2013 it's hard to estimate the daily loads, which means daily rate of sedimentation.

Moreover, are you sure that this basin has never been emptied - even partially - in these 25 years?

And what are its dimensions? Is the reservoir nourished by a river? Do you have any data on the river flow? Is there an effluent?

Your question without more data is too vague, not clear.

Actually, considering the whole time interval (in days) and the total weight of trapped sediments (tons), about 18.2 ton/day seems really a high value ...

Best,

Carlo

Dear Carlo Donadio and José Luis Casamor,

I most sincerely appreciate your responses. Indeed others i have asked back home are giving me the same responses. for Clarity sake i tabulate the background information as follows:

Dam year of construction: 1940

year of redredging: 1988

Initial bathymetries Before 2015: None

Bathymetric measurements between 2015 and now: 5 (at different seasonal times)

gauging station: None (relying on the down stream one about 18km away from the reservoir)

Source of Water into the reservoir: Surface run off and natural depression channel

Emptying or dredging between 1988 and now: None.

sediment measurements before 2014: None

Sediment measurement between 2014 and now: 3

Thanks once again, i thought one would have a Mathematical Model to desegregate the One time measurement into daily, montly and annual.

Hi Manoah, this seems a good start. I'll think about these new data and then contact you. Best, Carlo

The simple answer is to divide the number of days into the estimated tons of accumulated sediment. However this is an artificial figure as the accumulation of sediment varies from day to day. For example, after a bushfire in the watershed and a burst of heavy rainfall an enormous amount of sediment will arrive in the reservoir, while in a quiet period almost no sediment might arrive over an extended period of time.

Dear Carlos and Mills,

Thanks for the responses. I really also trying to figure around developing a mathematical model that can give best daily estimates. If this can happen, it would really be a good contribution to the science.

Hi Manoah,

I am preparing a table with the main data to do a tentative calculation of sediment load combining 2 SWs I use (Idro and Fournier, both in Italian). This SWs need to input more data: maximum monthly rainfall (mm/years), total annual rainfall (mm/years), maximum and minmum elevation (m asl) of the watershed, average gradient of the hydrographic basin. Do you have them? If yes, please send me them.

Due to the lack of some data in this specific case, the procedure is to use the first SW, then the other SW to control - through several tentatives - if there is an acceptable result (differences

Hi,

I have this information, let me just put in one folder and send. Latest tomorrow.

Excited to try it out.

Meanwhile I am also using a Sedimeter SM3A to estimate daily, monthly and rainy seasonal sediment loads. in cubic. m.

Ok, send me the data when you want.

I'll prepare a short description of the adopted procedure.

Best, Carlo

data sent to your inbox.

thanks

I've got it.

Thnx.