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Hydrologic Response Units

If regular HRUs are used in a SWAT+ setup, there is one main file, , which references several other files specifying the HRU properties. The properties of HRU-lte objects are defined in .

hru-data.hru

This file contains pointers to several files that specify the HRU properties.

Field

Description

Type

ID of the HRU

integer

Name the of HRU

string

id (hru-data.hru)

Unique ID of the HRU

The ID of the HRU is a primary key referenced by hru in hru.con. All IDs in the hru-data.hru file must be unique.

name (hru-data.hru)

Name of the HRU

The SWAT+ Editor assigns a name to every object, which is typically the abbreviation of the object type followed by the object number in QSWAT+. However, the name of the HRU is not used by SWAT+, so the user may change it.

topo

Pointer to the topography file

The pointer to the topography file is a foreign key referencing in .

hydro

Pointer to the hydrology file

The pointer to the hydrology file is a foreign key referencing in .

soil

Pointer to the soil file

The pointer to the soil file is a foreign key referencing name in soils.sol.

lu_mgt

Pointer to the land use and management file

The pointer to the land use and management file is a foreign key referencing name in landuse.lum.

soil_plant_init

Pointer to the soil and plant initialization file

The pointer to the soil and plant initialization file is a foreign key referencing in .

surf_stor

Pointer to the wetland file

The pointer to the wetland file is a foreign key referencing in .

snow

Pointer to the snow file

The pointer to the snow file is a foreign key referencing name in snow.sno.

field

Pointer to the field file

The pointer to the field file is a foreign key referencing name in field.fld.

hru-lte.hru

Field

Description

Type

Unit

Default

Range

ID of the HRU-lte

integer

n/a

id (hru-lte.hru)

ID of the HRU-lte

The ID of the HRU-lte is a primary key referenced by in . All IDs in the hru-lte.hru file must be unique.

name (hru-lte.hru)

Name of HRU-lte

area

HRU-lte drainage area

cn2

Condition II Curve Number

cn3_swf

Soil water factor for CN3

0 = field capacity

1 = saturation

t_conc

Time of concentration

soil_dp

Soil profile depth

perco_co

Soil percolation coefficient

slp

Land surface slope

slp_len

Land surface slope length

et_co

ET coefficient

aqu_sp_yld

Specific yield of the shallow aquifer

alpha_bf

Baseflow alpha factor

revap

Revap coefficient

rchg_dp

Percolation coefficient from shallow to deep aquifer

sw_init

Initial soil water (fraction of available water capacity)

aqu_init

Initial shallow aquifer storage

aqu_sh_flo

Initial shallow aquifer flow

aqu_dp_flo

Initial deep aquifer flow

snow_h2o

Initial snow water equivalent

lat

Latitude

soil_text

Soil texture

trop_flag

Tropical flag

0 = non-tropical

1 = tropical

grow_start

Start of growing season for non-tropical/start of monsoon initialization period for tropical

points to lum_std.dtbl file

grow_end

End of growing season for non-tropical/start of monsoon initialization period for tropical

points to lum_std.dtbl file

plnt_typ

Plant type

stress

Plant stress

pest, root, restriction, soil quality

pet_flag

Potential ET method

SWAT+ offers two options for estimating PET for HRU-lte:

p_t - Priestley-Taylor method

harg - Hargreaves method

irr_flag

Irrigation code

no_irr - no irrigation

irr - irrigation

irr_src

Irrigation source

outside_bsn - outside basin

shal_aqu - shallow aquifer

deep_aqu - deep aquifer

t_drain

Design subsurface tile drain time

usle_k

USLE soil erodibility factor K

usle_c

USLE cover factor C

usle_p

USLE support practice factor P

usle_ls

USLE slope length and slope factor LS