Modelling of rainwater reduction and hydrological performance of selected green infrastructure (GI) facilities in urban catchments

Figures & Tables

The basic measures of fitness coefficients for built SWMM model

Indicator		Description	Formula	Obtained value	Assessment	Literature
NSEC	Nash-Sutcliffe Efficiency Coefficient	Compare the results of model’s response and measurement data	1−∑t=1TQot−Qst2∑t=1TQot−Qo¯2 1 - {{\mathop \sum \nolimits_{t = 1}^T {{\left( {Q_o^t - Q_s^t} \right)}^2}} \over {\mathop \sum \nolimits_{t = 1}^T {{\left( {Q_o^t - \overline {{Q_o}} } \right)}^2}}}	0.885	-∞ - 1; very good	[Titterington et al. 2017], [Moriasi et al. 2007], [Lin et al. 2017]
ISE	Integral Square Error	The accuracy of the matching between simulated and observed data	∑t=1TQot−Qst2∑t=1TQot {{\sqrt {\mathop \sum \nolimits_{t = 1}^T {{\left( {Q_o^t - Q_s^t} \right)}^2}} } \over {\mathop \sum \nolimits_{t = 1}^T Q_o^t}}	0.02	0 – 3; excellent	[Shamsi et al. 2017]
RMSE	Root Mean Square Error	Differences between observed and simulated values	∑t=1T(Qot−Qst2T) \sqrt {\sum\limits_{t = 1}^T {({{{{\left( {Q_o^t - Q_s^t} \right)}^2}} \over T})} }	0.442; < 0.5*1.307	less than half of the standard deviation; good	[Singh et al. 2004], [Moriasi et al. 2007]

Land use	Area
	ha	%
Roofs	1.12	26.9
Roadways, pavement, alleys	0.40	9.6
Single- and multi-family residential land	2.17	52.0
Biologically active areas	0.48	11.5
TOTAL	4.17	100.0

Layer	Parameter	Unit	Bio-retention cells (BC)
Surface layer	Berm height	mm	250
	Vegetation volume	share	0.1
	Surface roughness	–	0.3
	Surface slope	%	1
	Swale Side Slope	run/rise	–
Soil layer	Thickness	mm	600
	Porosity	share vol.	0.45
	Field capacity	share vol.	0.121
	Wilting point	share vol.	0.057
	Conductivity	mm/hr	91
	Conductivity slope	–	44
	Suction head	mm	50
Storage layer	Thickness	mm	400
	Void ratio	voids/solids	0.54
	Seepage rate	mm/hr	2.6
	Clogging factor	–	0
Drain	Flow coefficient	mm/hr	5.4*
	Drain exponent	–	0.5
	Offset height	mm	200

	Scenario S₀	Scenario S₁	Scenario S₂	Scenario S₃	Scenario S₄	Scenario S₅	Scenario S₆	Scenario S₇
no LID
Max flow [LPS]	4.6	449.2	464.0	454.8	393.1	359.3	349.9	266.2
Total volume [m³]	17	539	752	916	953	1008	1072	1139
with LID
Max flow [LPS]	0.0	17.5	31.6	31.7	25.2	22.6	22.1	17.6
Total volume [m³]	0	29	56	111	134	167	204	246
reduction
Max flow [LPS]	100%	96%	93%	93%	94%	94%	94%	93%
Total volume [m³]	100%	95%	93%	88%	86%	83%	81%	78%

Scenario	S₀	S₁	S₂	S₃	S₄	S₅	S₆	S₇
Total Inflow (m³)	37.9	658.2	987.1	1234.8	1304.7	1404.0	1512.8	1629.2
Surface and Drain Outflow (m³)	0.0	32.7	133.6	273.6	318.7	385.4	458.9	538.8
Average inflow (L/m²)	0.008	0.139	0.208	0.260	0.275	0.296	0.319	0.344
Average outflow (L/m²)	0.000	0.007	0.028	0.058	0.067	0.081	0.097	0.114
Average reduction (%)	100	95	86	78	76	73	70	67

	Scenario S₀	Scenario S₁	Scenario S₂	Scenario S₃	Scenario S₄	Scenario S₅	Scenario S₆	Scenario S₇
Precipitation duration	90 min (4.2 mm)	15 min	30 min	45 min	60 min	90 min	120 min	180 min
Average rainfall intensity [LPS/ha]*	7.8	273.32	175.33	134.52	105.37	74.81	59.55	42.46
Total precipitation p = 10% [mm]	4.2	24.60	31.56	36.32	37.93	40.40	42.88	45.86
Precipitation intensity p = 10% [mm/hr]	2.80	98.40	63.12	48.43	37.93	26.93	21.44	15.29

Description	Imperv [%]		N Imperv	N Perv	Dstore Imperv [mm]	Dstore Perv	Zero Imperv [%]	Width
Description	min	max	N Imperv	N Perv	Dstore Imperv [mm]	[mm]	Zero Imperv [%]	A [m]
Building roofs-BUBD	87.47		0.010	0.045	3.69	3.69	36.00	0.7
Other roadway-SKJZ08	13.1	36.0	0.015	0.300	1.20	5.08	40.00	0.3
Local roadway-SKJZ06	34.6	49.5	0.010	0.300	1.20	5.08	40.00
Alley-SKRP01	2.0	3.2	0.011	0.280	1.20	5.08	40.00
Grass vegetation-PTTR01	1.0	2.5	0.140	0.280	5.08	7.62	20.00	0.3
Orchard-PTUT03	1.1	2.88	0.210	0.280	5.08	7.62	20.00
Single-family dwelling-PTZB02	2.0	4.02	0.105	0.280	5.08	7.62	20.00

No.	Scenario	S₀	S₁	S₂	S₃	S₄	S₅	S₆	S₇
	*share LID storage in rainfall volume*
1A	Rainwater volume [m³]	365	2137	2742	3156	3296	3510	3725	3984
1B	Final LID storage [m³]	41	788	970	1024	1036	1057	1081	1108
1	Average share [%]	11%	37%	35%	32%	31%	30%	29%	28%
	*LID hydrological performance*
2A	Average inflow [L/m²]	0.008	0.139	0.208	0.260	0.275	0.296	0.319	0.344
2B	Average outflow [L/m²]	0.000	0.007	0.028	0.058	0.067	0.081	0.097	0.114
2	Average reduction [%]	100%	95%	86%	78%	76%	73%	70%	67%
	*average total inflow to LID with full reduction*
3	Fully reduced inflow [L/m²]	0.76	5.79	2.30	2.85	3.13	3.28	3.46	4.25
	*total outfall volume reduction*
4A	Total volume [m³]	17	539	752	916	953	1,008	1,072	1139
4B	Reduced volume [m³]	0	29	56	111	134	167	204	246
4	Average reduction [%]	100%	95%	93%	88%	86%	83%	81%	78%
	*outfall peak flow reduction*
5A	Peak flow [LPS]	4.60	449.16	464.03	454.78	393.10	359.34	349.85	266.20
5B	Reduced peak flow [LPS]	0.00	17.51	31.63	31.66	25.19	22.57	22.05	17.58
5	Average reduction [%]	100%	96%	93%	93%	94%	94%	94%	93%