# Groundwater recharge estimation in semi-arid zone: a study case from the region of Djelfa (Algeria)

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## Abstract

Deficiency of surface water resources in semi-arid area makes the groundwater the most preferred resource to assure population increased needs. In this research we are going to quantify the rate of groundwater recharge using new hybrid model tack in interest the annual rainfall and the average annual temperature and the geological characteristics of the area. This hybrid model was tested and calibrated using a chemical tracer method called Chloride mass balance method (CMB). This hybrid model is a combination between general hydrogeological model and a hydrological model. We have tested this model in an aquifer complex in the region of Djelfa (Algeria). Performance of this model was verified by five criteria [Nash, mean absolute error (MAE), Root mean square error (RMSE), the coefficient of determination and the arithmetic mean error (AME)]. These new approximations facilitate the groundwater management in semi-arid areas; this model is a perfection and amelioration of the model developed by Chibane et al. This model gives a very interesting result, with low uncertainty. A new recharge class diagram was established by our model to get rapidly and quickly the groundwater recharge value for any area in semi-arid region, using temperature and rainfall.

## Keywords

Groundwater recharge Hybrid model Semi-arid area Chloride mass balance Djelfa## Introduction

In semi-arid area, the groundwater resources are the most requested to meet the water to supply population, industrial and agricultural activities. In the world 50 % of drinking water, 40 % of water intended for industrial activities, and 20 % of water for agriculture are groundwater (Foster and Chilton 2003). The daily water needs of the population increases with population growth. Therefore the concepts of sustainable management of water resources become indispensable. For that one of the major problems encountered in the management of groundwater resources is the evaluation of groundwater recharge to quantify groundwater reserves. Groundwater recharge is a difficult parameter; its estimation contains several constraints linked to the topography, the soil, the density of vegetation cover, geological heterogeneity and reliability of hydro-climatic data (Sibanda et al. 2009). Several approaches are followed to quantify this parameter which represents the core of groundwater management.

*Reviews of groundwater recharge estimation technique* Lot of methods were used in the entire world to quantify the rate of the groundwater recharge, as reported by Kinzelbach et al. (2002) and Osterkamp et al. (1995).

The most used method is the Hydrological water budget (HWB), Chemical tracers [Chloride mass balance (CMB); and isotopic tritium profile method] (Scanlon et al. 2006), and the soil water budget; and the water fluctuation level (WFL) method, Aquifer recharge rate relate directly to the soil texture, rock properties and to the velocity of infiltration and to the intensity of precipitation (Bonta and Müller 1999). Hydrological modeling shows a very rapid progress in the last decade due to the evolution of informatics systems (hard and software).

*Limit of estimation of groundwater recharge* The previous methods have a limit applications (water level fluctuation methods, Darcyian methods, soil budgets methods, and hydrological modeling) because of many problems in the fields of study: the geological heterogeneous of the study area; high depth of soil (up to 30 m), the fracturation density in some cretaceous deposits, and lack of data (water level control wells, spring source discharge, aquifers properties; and soils depth).

The hydrological balance has a high limit of groundwater estimation; this is principally due to the high uncertainty in the estimation of Real evapotranspiration (Turc, Penman, and Thornthwaite) methods. For this problem the model of Chibane et al. was derived to solve these problems. To minimize the high uncertainty in estimation of recharge using the Hydrological water budget (some hydrological balance in semi-arid give a negative balance) which makes estimation of recharge very complicated.

## Materials and methods

In this paper we have combined three methods to evaluate the GWR: using the Chloride mass balance (CMB), a hydro-geological model based on soil and rock characteristic and a new Hybrid model. The combination between these methods lets us to adjust a general model to evaluate with high usefulness and with small error the rate of GWR.

### Area of study

#### Geological data

Our area is formed by different geological deposits, recently we found Mio-plioquaternary deposits, it is formed by Sandy loams and limestone crusts, also by clays and red marl and lenses chalky conglomerate-sandstone. Secondly we find the Santonian deposit is formed alternately by Limestone and marl and frequently by gypsum lenses. Thirdly the Turoniana deposit presents a high groundwater reservoir and it is formed by benches of Limestone to the top, marl and limestone in the middle part and gypsum at the base. Fourthly the Cenomanian deposits are composed of marl with few limestone and gypsum (Chibane and Ali-Rahmani 2015).

Fifthly we find the Albian deposits divided into two groups: the Upper Albian who has formed alternately by Limestone and marl and the Lower Albian formed by massive fine sandstone intercalated with gray clays. The two groups formed a high capacity reservoir. The next deposit is the Aptian composed alternately from Limestone and Marl. The Barremien was composed of Alternating sandstone and sandstone clay red with a cross-bedded common in sandstone and lot of joints and cracks. The Neo-comian deposits were specified by the presence of Clay sandstone rocksat in the base and dolomite limestone and calcareous sandstone. The Triassic is the last formation it was formed by Clay ‘swine-colored sandstone and shale and marl colored with some inclusion conglomerates (Chibane 2010).

#### Hydro-climatic study

The region of Djelfa is characterized by a semi-aride climate with a cold winter and a warm summer.

### Chloride mass balance

In many research papers the chloride mass balance method was applicated to evaluate the groundwater recharge in semi-arid area this methods assume that chloride does not have any chemical interaction with soils (Nimmo et al. 2005). This technique has been used in this work to give a reference value of GWR to calibrate the new hybrid model. The chloride is a conservative tracer used in hydrogeological studies; this technique is based on the ratio between the chloride concentration in rainfall and the chloride concentration in groundwater samples.

No previous work in the field of study has used the CMB method. 60 samples of rainfall and Groundwater were collected, prepared and analyzed in the laboratory for the hydrological year (2013/2014).

*GWR*recharge in mm,

*P*average annual rainfall in mm, \(\left[ {\text{Cl}} \right]_{\text{p}}\) concentration of chloride in precipitation in mg/l, \(\left[ {\text{Cl}} \right]_{\text{gw}}\) concentration of chloride in groundwater in mg/l.

### The hydrogeological approach

*ϕ*the result of variation of recharge using the hydrogeological model shown in Fig. 5.

Calcul methodology for a given type of Rock

iD | Rock | Infiltration coefficient ( | Rainfall P (mm) | GWR (mm) | Mean GWR (mm) |
---|---|---|---|---|---|

1 | GRAVELS | 6 | 320 | \(GWR = \frac{6.320}{100} = 19.2\) | \(GWR = \frac{19.2 + 6.4}{2} = 12.8\) |

2 | Limestone | 2 | 320 | \(GWR = \frac{2.320}{100} = 6.4\) |

*ϕ*to derive a linear relationship (Eq. 3):

*ϕ*geological factor characterising the rock, and

*P*annual rainfall given in mm.

*ϕ*is given in Table 2 as given by Banton and Et Bangoy (1997) and Castany (1982, modified).

Type of rock | Coefficient of infiltration % | Infiltration |
---|---|---|

Gravels | 6 | High |

Alluvium | 6 | |

Sandstone | 4 | Medium |

Sand | 4 | |

Sandy loam | 4 | |

Silt | 4 | |

Clay loam | 4 | |

Clayey sand | 4 | |

Marl | 4 | |

Sandy clays | 4 | |

Limestone | 2 | Low |

Crusting | 2 | |

Dolomite | 2 | |

Gypsum | 1 | Very low |

Clays | 1 | |

Silt | 1 | |

Soil of Sebkhas | 1 |

### The hybrid model

Combination between geological properties of the aquifers (rocks types) and the hydroclimatic data characterizes the semi-aride area and we derive a new mathematical formulae to evaluate the Groundwater recharge in these area.

Many empirical formulas used to explicit the hydrological water budget components underestimate the Recharge (GWR), especially in semi-arid areas.

This makes it difficult to look for other estimation methods, to give an approach value of recharge to sustainably manage the groundwater resources.

Combinations between the empirical formulas make us to formulate a new general model to estimate Groundwater recharge in semi-arid area.

#### Equation of model

*R*) is given by the following equation (Eq. 4):

*R*annual average recharge given in (mm),

*T*average annual temperature given in (°C),

*P*average annual rainfall given in mm.

#### Model of Chibane et al.

The model of Chibane et al. is a hydrological based model developed and designated to estimate GWR in semi-arid areas. it published in 2015. it uses the precipitation and average annual temperature as input. This model underestimates the recharge value for the medium rainfall values (*p* < 400 mm).

*φ*and

*α*coefficients depending on temperature, GWR

_{c}is annual groundwater recharge given in mm, and

*P*average annual precipitation given in mm.

## Results and discussion

Results of chloride mass balance method for the hydrological year of 2013/2014

Well ID | Cl-well (mg/l) | | pH | CE (µS/cm) | Cl-rain (mg/l) | Rainfall (mm) | Recharge (mm) |
---|---|---|---|---|---|---|---|

| 197.12 | 20.60 | 7.77 | | 3.23 | 300.00 | 4.92 |

DF1 | 90.76 | 28.30 | 7.84 | 518.00 | 3.65 | 300.00 | 12.06 |

DF4 bis | 76.58 | 24.60 | 7.96 | 529.00 | 3.55 | 300.00 | 13.91 |

DF4 | 73.03 | 24.70 | 8.15 | 565.00 | 3.58 | 300.00 | 14.71 |

DF5bis | 69.49 | 26.60 | 7.94 | 713.00 | 3.43 | 300.00 | 14.81 |

OSF1 | 44.67 | | | 822.00 | 3.40 | 300.00 | 22.83 |

OSF2 | 41.13 | 19.90 | 8.07 | 769.00 | 3.45 | 300.00 | 25.17 |

OSF3 | 48.22 | 27.00 | 8.13 | 853.00 | 3.47 | 300.00 | 21.59 |

OSF4 | 44.67 | 37.50 | 8.22 | 744.00 | 3.55 | 300.00 | 23.84 |

OSF5 | 48.22 | 37.40 | 7.95 | 1860.00 | 3.36 | 300.00 | 20.91 |

OSF6 | 48.22 | 17.90 | 7.96 | 1906.00 | 3.37 | 300.00 | 20.97 |

OSF7 | 87.21 | 17.30 | 7.94 | 2030.00 | 3.44 | 300.00 | 11.83 |

OSF8 | 51.76 | 16.30 | 7.96 | 1365.00 | 3.41 | 300.00 | 19.76 |

OSF10 | 58.85 | 22.70 | 7.84 | 1165.00 | 3.36 | 300.00 | 17.13 |

OSF11 | 151.03 | 25.80 | 8.53 | 1214.00 | 3.48 | 300.00 | 6.91 |

OSF12 | 239.66 | 23.60 | 7.82 | 1057.00 | 3.39 | 300.00 | 4.24 |

Statistic summary of chloride mass balance methods

Statistics | Cl-well (mg/l) | | pH | CE (µS/cm) | Cl-rain (mg/l) | Rainfall (mm) | Recharge (mm) |
---|---|---|---|---|---|---|---|

Mean | 85.66 | 24.18 | 8.01 | 1045.75 | 3.45 | 300.00 | 15.97 |

Max | 239.66 | 37.50 | 8.53 | 2030.00 | 3.65 | 300.00 | 25.17 |

Min | 41.13 | 16.30 | 7.77 | 518.00 | 3.23 | 300.00 | 4.24 |

Stdv | 57.21 | 6.26 | 0.18 | 489.78 | 0.10 | 0.00 | 6.48 |

Result of recharge [*R* (mm)] calcul using three models (hybrid model, hydrogeological model, and Chibane et al. models)

Year | | | R_Chibane et al. model | R_hybrid_model | R_HG_model |
---|---|---|---|---|---|

1979 | 654.79 | 15.16 | 26.55 | 20.66 | 22.26 |

1980 | 560.93 | 14.64 | 8.58 | 22.61 | 19.07 |

1981 | 379.51 | 15.68 | 1.68 | 13.49 | 12.90 |

1982 | 637.53 | 15.06 | 21.59 | 21.01 | 21.68 |

1983 | 355.25 | 15.61 | 1.28 | 13.37 | 12.08 |

1984 | 292.35 | 14.55 | 0.50 | 16.99 | 9.94 |

1985 | 409.21 | 15.70 | 2.29 | 13.89 | 13.91 |

1986 | 385.65 | 15.34 | 1.66 | 14.89 | 13.11 |

1987 | 536.42 | 16.37 | 9.85 | 13.52 | 18.24 |

1988 | 555.87 | 15.90 | 11.08 | 15.37 | 18.90 |

1989 | 502.37 | 16.18 | 6.67 | 13.65 | 17.08 |

1990 | 547.18 | 15.93 | 10.19 | 15.11 | 18.60 |

1991 | 632.36 | 14.39 | 16.70 | 26.77 | 21.50 |

1992 | 500.49 | 14.31 | 4.08 | 24.20 | 17.02 |

1993 | 406.18 | 15.30 | 2.03 | 15.41 | 13.81 |

1994 | 377.62 | 16.05 | 1.77 | 12.34 | 12.84 |

1995 | 386.63 | 15.71 | 1.82 | 13.49 | 13.15 |

1996 | 492.24 | 15.10 | 4.77 | 17.98 | 16.74 |

1997 | 382.46 | 15.94 | 1.82 | 12.71 | 13.00 |

1998 | 285.96 | 15.82 | 0.65 | 11.66 | 9.72 |

1999 | 392.01 | 16.41 | 2.19 | 11.60 | 13.33 |

2000 | 136.20 | 16.01 | 0.14 | 9.07 | 4.63 |

2001 | 184.62 | 16.69 | 0.26 | 8.58 | 6.28 |

2002 | 172.56 | 15.85 | 0.20 | 9.91 | 5.87 |

2003 | 296.02 | 16.01 | 0.75 | 11.30 | 10.06 |

2004 | 284.25 | 15.64 | 0.61 | 12.13 | 9.66 |

2005 | 268.00 | 16.03 | 0.56 | 10.87 | 9.11 |

2006 | 321.11 | 16.24 | 1.01 | 11.09 | 10.92 |

2007 | 340.84 | 15.70 | 1.12 | 12.83 | 11.59 |

2008 | 358.10 | 15.60 | 1.32 | 13.44 | 12.18 |

2009 | 403.66 | 15.75 | 2.19 | 13.62 | 13.72 |

2010 | 301.08 | 16.17 | 0.81 | 11.00 | 10.24 |

2011 | 519.54 | 14.78 | 4.58 | 20.58 | 17.66 |

2012 | 396.87 | 15.00 | 6.38 | 16.68 | 13.49 |

2013 | 300.18 | 14.54 | 5.01 | 17.21 | 10.21 |

Statistic summary of recharge (*R*) calcul

| | | R_hybrid_model | R_HG_model | |
---|---|---|---|---|---|

Mean | 398.74 | 15.58 | 4.65 | 14.83 | 13.56 |

Max | 654.79 | 16.69 | 26.55 | 26.77 | 22.26 |

Min | 136.20 | 14.31 | 0.14 | 8.58 | 4.63 |

Stdv | 128.520731 | 0.6077063 | 6.10548797 | 4.24072007 | 4.36970484 |

The correlation between the values of GWR estimated by the two methods gives a best.

The average annual ground water recharge given by the two models is between 13 and 15 mm. In the opposite side the mean value of recharge given by the model of Chibane et al. is 4 mm/year. These results confirm the relationship between the new hybrid model designated to the semi-arid area and the hydro-geological model applicated to estimate the groundwater recharge.

Performance of this model was proved using a statistical error mostly used in hydrological modelling as given by Chai and Draxler (2014).

Error of calcul for each model by tacking the hydrogeological model as a reference

Error | Chibane et al. model | Hybrid model |
---|---|---|

Nash | 0.52 | 0.54 |

MAE | 9.16 | 8.14 |

RMSE | 9.60 | 9.37 |

AME | 67.57 | 60.04 |

The methods of chloride balance give an average annual recharge about 16 mm/year which is compared to the hydrogeological model and the hybrid model (10 and 17 mm). In the opposite side the model of Chibane et al. give 0.54 mm/year. The CMB method confirms the results obtained by the two new models (Hybrid model and the Hydrogeological model).

The first class was started from less than 200 mm/year; where the GWR recharge is less than 15 mm/year, the second medium class is situated between 450 and 200 mm, the corresponding GWR is located between 15 and 32 mm/year; the high class started more than 400 mm/year, the GWR was up and more than 32 mm/year.

This new classification corresponds to the climate regime and the geological structure of the semi-arid area as explained by Goes (1999).

Isotopic study of the aquifer of region established by Chibane (2010) confirms that the recharge is medium and localised; the age of the groundwater is old, which proves that the recharge velocity is slow.

*Limit of model*This work is an attempt to find an equation which takes into account the properties of a semi-aride area (geological, hydro-climatic characteristics); however, the limit of application of this model is depending on the two parameters (rainfall, and temperature) (Table 8).

Limit of application of model used to evaluate recharge in semi-aride media

Model | Rainfall (mm) | Temperature (°C) |
---|---|---|

Chibane et al. | 400 < | 13 < |

Hydrogeological model | | – |

Hybrid model | 100 < | 13 < |

In the previous work of Chibane et al. the hydrological model was derived from the hydrological water budget, however, this model presents a high deviation in estimation of recharge for low precipitation value (*P* < 400 mm).

The hybrid model and the hydrogeological model work correctly when the average annual precipitation is lower than 600 mm, it work also correctly in arid and semi-arid zones.

The hybrid model was calibrated using chemical tracer methods (Chloride mass balance) to compare the rate of recharge in the study area vs the three models.

## Conclusions

In light of the result a good approximation was approached, and a best estimation of GWR with this new hydrological hybrid model was achieved.

The error types used to test the efficiency of the model confirm that this model gives a best estimation for the GWR in semi-arid area, in our case study of Djelfa (Algeria) where we have tested the model, it gives a very acceptable result. From Fig. 10 our region was located in the medium recharge interval with an average annual recharge between 15 and 32 mm. This new model can be used in all semi-arid areas which have an annual rainfall less than 700 mm/year.

The application of the chloride mass balance gives us a very interesting result (*R* = 16 mm/year) which is similar to the results obtained by the hybrid model for the same year. The combinations between these results let us to use the new hybrid model with low uncertainty in groundwater recharge assessment.

## References

- Ali Rahmani SE, Chibane B, Hallouz F, Boucefiène F (2015) Study of the relationship between drought index and Groundwater recharge, case of an aquifer in a semi-arid area. In: Proceedings of the international conference on African large river basins hydrology, Hammamet, Tunisia, from 26 October 2015 to 30 October 2015Google Scholar
- Banton O, Et Bangoy LM (1997) Hydrogéologie - multiscience environnementale des eaux souterraines, Aupelf Uref, Presses De l’Université Du Québec, p 460Google Scholar
- Bonta JV, Müller M (1999) Evaluation of the Glugla method for estimating evapotranspiration and groundwater recharge. Hydrol Sci J 44(5):743–761. doi: 10.1080/02626669909492271 CrossRefGoogle Scholar
- Castany G (1982) Principes et méthodes de L’hydrogéologie, Dunod, Paris, France, p 249Google Scholar
- Chai T, Draxler RR (2014) Root mean square error (RMSE) or mean absolute error (MAE)?—arguments against avoiding RMSE in the literature. Geosci Model Dev. 7:1247–1250CrossRefGoogle Scholar
- Chibane B (2010) Hydrogeological and hydrogeochemical gtudy in semi-arid area: case study of the Djelfa region, PhD thesis in hydrogeology, FSTGAT, USTHB, AlgeriaGoogle Scholar
- Chibane B, Ali-Rahmani SE (2015) Hydrological based model to estimate groundwater recharge, real evapotranspiration and runoff in semi-arid area, LARHYSS J N°23:Issue 23, ISSN:1112-3680Google Scholar
- Foster SSD, Chilton PJ (2003) Groundwater: the processes and global significance of aquifer degradation. Phil Trans R Soc Lond B 358:1957–1972CrossRefGoogle Scholar
- Goes BJM (1999) Estimate of shallow groundwater recharge in the Hadejia Nguru Wetlands, semi-arid North-Eastern Nigeria. Hydrogeol J 7:294–304
**(Springer)**CrossRefGoogle Scholar - Kinzelbach W, Aeschbach W, Alberich C, Goni IB, Beyerle U, Brunner P, Chiang W-H, Rueedi J, Zoellmann K (2002) A survey of methods for groundwater recharge in arid and semi-arid regions. Early warning and assessment report series, UNEP/DEWA/RS.02-2. United Nations Environment Programme, Nairobi, Kenya, ISBN 92-80702131-3Google Scholar
- Nimmo JR, Healy RW, Stonestrom DA (2005) Aquifer recharge. In: Anderson MG, Bear J (eds) Encyclopedia of hydrological science: part 13. Groundwater, vol 4. Wiley, Chichester, pp 2229–2246. doi: 10.1002/0470848944.hsa161a. (http://www.mrw.interscience.wiley.com/ehs/articles/hsa161a/frame.html)
- Osterkamp WR, Lane LJ, Menges CM (1995) Techniques of ground-water recharge estimates in arid/semi-arid areas, with examples from Abu Dhabi. J Arid Environ 31:349–369CrossRefGoogle Scholar
- Scanlon BR, Keese KE, Flint AL, Flint LE, Gaye CB, Edmunds WM, Simmers I (2006) Global synthesis of groundwater recharge in semiarid, and arid regions. Hydrol Process 20:3335–3370CrossRefGoogle Scholar
- Sibanda T, Nonner JC, Uhlenbrook S (2009) Comparison of groundwater recharges estimation methods for the semi-arid Nyamandhlovu area, Zimbabwe. Hydrogeol J 17:1427–1441
**(Springer)**CrossRefGoogle Scholar - Vivoni ER, Aragón CA, Malczynski L, Tidwell VC (2009) Semiarid watershed response in central New Mexico and its sensitivity to climate variability and change. Hydrol Earth Syst Sci 13:715–733CrossRefGoogle Scholar

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