Water_Rights

Water allocation tables are very specific to the watershed and new feature in SWAT+. We recommend working with the model development team if you are unsure. Because this is a new addition, the interface is still limited if you're trying to build a large table with many source and demand objects.

Field

Description

Type

name

name of the water allocation object

string

rule_typ

rule type to allocate water

string

src_obs

number of source objects

integer

dmd_obs

number of demand objects

integer

cha_ob

channel object (enter y=yes there is a channel object; enter n=no channel object (only one per water allocation object)

string

Water source objects

Field

Description

Type

num

demand object number

integer

ob_typ

object type (channel=cha; reservoir=res; aquifer=aqu; unlimited source=unl)

string

ob_num

number of the object type

integer

limit_mon

minimum monthly values for object type:

  • channel flow (m3/s)

  • minimum reservoir level (fraction principal);

  • maximum aquifer depth (m);

real

Demand objects

Demand. Demand can be irrigation demand from an hru, municipal demand, or demand to transfer to another source object (channel, reservoir, aquifer). For irrigation demand, the hru number, decision table for triggering irrigation, and irrigation depth (mm) are input. For municipal demand, a muni number is input. The user then has the option to input an average daily demand or a recall name that can be daily, monthly, or annual. For transfer demand, the trans number is input and the user can input an average daily demand or a decision table to specify demand.

Treatment. Treatment is designed for municipal treatment plants or industrial plants that treat or change the water chemistry. There are 2 options – 1) recall where you can specify the amount of return flow and 2) delivery where you can specify the change in flow and chemistry.

Receiving. This can be used to return the treated municipal water (point sources) or to transfer (divert) water to other objects. The simple option is the input the return object and number. Or a decision table can be input to condition the diversions to multiple objects. Inputting “lost” assumes the water is diverted out of the basin.

Source Allocation. The sources are listed in order of selection and the fraction from each source is input. The other input is compensation – if other sources are not available, the current source may be allowed to compensate for the demand. The model goes through all sources in the order listed and allocates based on the fractions. The model loops through the sources again, checking to see if compensation is allowed

Field

Description

Type

num

demand object number

integer

ob_typ

hru (for irrigation) or muni (muncipal) or divert (interbasin diversion)

string

ob_num

number of the object type

integer

withdr

withdrawal type - average day or recall for muni and divert; irrigation for HRU

string

amount

m3 per day for muni and mm for HRU

real

right

water right (sr=senior; jr=junior)

string

treat_typ

recall for inputting a recall object and treat for a treatment object

string

treatment

pointer to the recall or delivery ratio file

string

rcv_ob

receiving object (channel, reservoir, aquifer) - no decision table, all return to this object

string

rcv_num

receiving object number

integer

rcv_dtl

receiving object decision table - to condition water transfers and diversions

string

dmd_src_obs

number of source objects available for the demand object

integer

SWAT+ Documentation