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All Topics | Topic "Tailwater elevation"
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Author Message
Mr. Ahmed Rafique

Subject: Tailwater elevation   
Posted: 11/7/2016 Viewed: 12892 times
What exactly is Tailwater elevation?

My understanding is, this is the level where turbines are installed in the reservoir. Let us assume that minimum reservoir level is 1300 ft AMSL, water level in reservoir is at 1350 ft AMSL and turbines are installed at 1310 ft AMSL. Should I use 1310 ft as tailwater level or 40 ft as tailwater level?


Ms. Stephanie Galaitsi

Subject: Re: Tailwater elevation   
Posted: 11/7/2016 Viewed: 12876 times
Dear Ahmed,

Have a look at the topic Hydropower Calculations calculations in the Help menu. For reservoirs, the height that the water falls in the turbines is equal to the elevation at the beginning of the month minus the tailwater elevation.

Thus, in your example, you should use 1310 masl as the tailwater elevation. WEAP will calculate the "drop elevation" as the difference between the elevation of the water in the dam (determined by the volume elevation curve) and the tailwater elevation.

Mr. Ahmed Rafique

Subject: Re: Tailwater elevation   
Posted: 11/7/2016 Viewed: 12867 times
Hi Stephanie,

Eng. Hùng Việt

Subject: Re: Tailwater elevation   
Posted: 2/5/2017 Viewed: 12377 times

could you please tell me how to input Tailwater elevation into WEAP, because Tailwater elevation depend on discharge of reservoir through turbine.

i think, in WEAP has a function to describe that relationship

i hope will receive ASA from you

many Thanks
Ms. Stephanie Galaitsi

Subject: Re: Tailwater elevation   
Posted: 2/6/2017 Viewed: 12362 times
Dear Hung,

The tailwater elevation does not depend on the discharge of the reservoir through the turbine - the tailwater elevation stays constant in WEAP. It is the elevation that the water is released at (the elevation of the outlet of the reservoir).

You can enter the tailwater elevation under in the reservoir under the tab "Hydropower" and the sub-tab "Tailwater elevation."

Have a look at the topic Hydropower Calculations calculations in the Help menu to better understand how the reservoir is modeled.

Topic "Tailwater elevation"