Quantifying the streamflow response to groundwater abstractions for irrigation or drinking water at catchment scale using SWAT and SWAT–MODFLOW

Environmental Sciences Europe

Table 8 Average annual stream flow change (2002–2015) at subbasin 13 outlet and subbasin 18 outlet for each abstraction scenario from no-wells scenario and the corresponding annual abstraction simulated in SWAT and SWAT–MODFLOW

Scenarios		Scenario 2 (Only drinking water wells)		Scenario 3 (Only irrigation wells)		Scenario 4 (Both drinking water and irrigation wells)
Model		SWAT	SWAT-MODFLOW	SWAT	SWAT-MODFLOW	SWAT	SWAT-MODFLOW
Average annual stream flow decrease(−) or increase(+) (10⁶ m³ year⁻¹)	Subbasin 13 outlet	− 0.024	− 1.10	0.61	0.24	0.59	− 0.73
	Subbasin 18 outlet	− 0.12	− 2.53	1.60	− 0.55	1.48	− 1.79
Annual abstraction (10⁶ m³ year⁻¹)	Subbasins 4-5, 7-13	1.10	1.28	17.86	19.45	18.96	20.73
Annual abstraction (10⁶ m³ year⁻¹)	The entire cathment excluding subbasin 19	4.01	3.96	40.54	39.26	44.55	43.22

Subbasin 13 outlet receives streamflow from subbasins 4–5, 7–13; Subbasin 18 outlet receives streamflow from the entire catchment excluding subbasin 19