Initializing reservoir storage

[dprincz]

Mohamed Ahmed:

Is there a way to set the initial condition(s) for the reservoirs in MESH? Currently, they are initialized as empty.

[dprincz]

You can initialize them based on lake level input. If lake area lake_area and elevation lake_elv are provided, it's initialized to store1 = lake_elv*lake_area and store2 = store1, and skips trying to back calculate it using the equations.

It happens in flowinit:

!        For control with rating curve, use rating curve.
!        For controlled reservoirs, just use channel stoage rule
!        (above) so we at least have some value.
        if(b1(k).gt.0.0.and.b2(k).gt.0.0)then
           if(lake_area(k).gt.0.0.and.lake_elv(k,kt).gt.0.0)then
              store1(n)=lake_elv(k,kt)*lake_area(k)
           elseif(b6(k).gt.0.0.and.lake_elv(k,kt).gt.0.0)then
              store1(n)=max(0.0_4,lake_elv(k,kt)-b7(k))*b6(k)
           elseif(b3(k).eq.0.0)then
              store1(n)=(qo2(n)/b1(k))**(1.0_4/b2(k))
           elseif(b3(k).gt.0.0)then
              store1(n)=10.0
              trialq=0.0
              do while(trialq.lt.qo2(n))
                 store1(n)=2.0_4*store1(n)
                 trialq=store1(n)*(b1(k)+store1(n)*(b2(k)+store1(n)*
    *               (b3(k)+store1(n)*(b4(k)+b5(k)*store1(n)))))
              enddo
           endif
           store2(n)=store1(n)
        endif

You have to populate those values in reservoir.tb0. You'll see them copied in rte_module:

lake_area = real(fms%rsvr%rls%area, kind(lake_area))
lake_elv(:, 1) = real(fms%rsvr%rls%zlvl0, kind(lake_elv))

The keywords are :ReachArea and :InitLvl in units of m**2 and m, respectively. They're specified and provided in the header of the tb0 file, along with the other reservoir attributes.

These fields cannot be specified using the txt format file.

[fuadyassin]

If you are using MESH_input_reservoir.tb0, there is an option to define the water level and area of a reservoir using the keywords:ReachArea and :InitLvl. Define them along with the coefficients, and it will initialize the reservoir from the specified level and back calculates the storage values from the level.

Make sure you are using RUNMODE runrte in your run option file.

Please note that this option will not work with MESH_input_reservoir.txt.

[kasra-keshavarz]

copying @MIsmlAhmed

[MIsmlAhmed]

Thanks all for your responses. That's helpful.

[mee067]

Note that the above does not apply in the case of using DZTR and initial values are read from the DZTR parameter file

[dprincz]

Very good point. Fuad mentioned this but it wasn't captured when the conversation was transferred.