Groundwater Recharge Evaluation on The Duhok Dam Reservoir by Using (SWBAPP) Model

Article Info Abstract Article History Received Nov 26, 2021 Revised Dec 13, 2021 Accepted Jan 15, 2022 Groundwater recharge has been calculated of Duhok Dam District, Kurdistan region of Iraq by using soil water balance parameters, because of limited sources of water. The study area of 228.96 km. The main purpose of this paper is to apply a water balance concept with using (https://livingatlas.arcgis.com/waterbalance/) website data models in the Duhok dam basin to describe the groundwater recharge. The influence of groundwater recharge on the rainfall-runoff process was investigated in order to have a better knowledge of the storage runoff water in the Duhok dam lake, the annual groundwater change is (0.4mm, 1mm, -1mm, 12.3mm and 1.3mm) for the since (2016-2017, 2017-2018, 2018-2019, 2019-2020 and 2020-2021) (respectively); depending on the rainfallrunoff amount and the soil moisture content (19.75%, 19.41%, 29.33%, 6.5% ) above average for the since (2016-2017, 2017-2018, 2018-2019, 2019-2020) (respectively) which lead to be water surplus, but at since (2020-2021) soil moisture content was below average (-8.3%) lead to decrease groundwater storage (deficit water is happen), Finally, all of the results of water balance parameters indicate the reservoir of Duhok dam basin need to more rainfall to renewable (2021-2022) hydrological year. Keywords


Introduction
Dams are one of the most important human interventions in the water cycle, delivering massive amounts of water for a number of cultural needs such as irrigation and power generation (drinking water, agriculture, and recreation). They also make floods and droughts less likely [1]. Groundwater may be a critical source of water in semi-arid climates, since it is protecting from the tall vanishing rates that affect surface water bodies. The long-term viability of groundwater bodies is therefore critical, and induced groundwater recharge is one of the most common strategies for enhancing a groundwater body's long-term supply [2]. Overseen aquifer revive frameworks may be more viable than expanding surface store capacities, especially under climate change conditions [3], and may moreover be the foremost financially and socially doable arrangement for coordinates water asset administration [4]. Water balances are used to guide water management in all population gatherings in different cities and villages, including those that do not have water scarcity. We found all the analyzed recharge rate over a twenty-one-year period from (2000 to 2021) concluded in the relationships that prominent of monthly average of rainfall amount between different water balance parameters by collection the database from water balance application with 0.25-degree spatial resolution (~30 km) for NASA: which approved by (Ersi, USGS: Esri, HERE, Garmin, FAO, NOAA, USGS).
Many types of hydrologic assessments, including assessments that concern water availability, water quality protection, streamflow and riparian-ecosystem management, aquifer replenishment, groundwaterflow modeling, and contaminant transport, require accurate estimates of groundwater recharge's spatial and temporal distribution. These recharge estimates are often key to understanding the effects of land-use change in urban, industrial, and agricultural regions. As the demand for science-based hydrologic management grows, so does the need for reliable and practical methodologies to calculate groundwater recharge rates [5].
The first Goals of this research are to evaluate groundwater storage within the reservoir. The second objective is to evaluate the average Rainfall-Runoff rate which flow towards within the Duhok Dam Lake.
The last one is to observe the temporal variation of water balance parameters and identify effect everyone on the groundwater storage.

Study Area
Duhok Dam could be a tall soil fill dam with a central clay center and rock shell on Duhok Waterway,

Climate
According to the increasing ratio of rainfall in Iraq's northern area, the mean annual summation of rainfall appears to have a symmetrical increasing trend from southwest to north-east. In these places, terrain, atmospheric depression, and the kind of air masses flowing in from the surrounding areas all play a part in the variation of yearly rainfall values. Iraq's climate is categorized as continental and subtropical semi-arid, including mountains sections in the north-east and north classified as Mediterranean [7]. With the surrounding high mountains exerting an expressed influence. Summers are dry and hot, while winters are wet and rainy; however, cold weather prevails in the winter, with snowfall on the high mountains. The rainy season lasts in October until May, and the year rest is dry in mostly. Every year, the region receives about 535 mm of rains. The temperature contrast between summer and winter is critical. The yearly average temperature is 19.5°C, with sand and silt brought in by north-west winds in the summer. While. North-east winds prevail in the winter. Table 2. illustrate the soil moisture and meteorological data of the Duhok dam basin.

Land Cover
Scattered oak trees, open forest, and bushes on unstable slopes make up around 23% of the area covered by poor forest and woodland. Due to soil erosion and severe erosion, lands in the Sindor and Bajlor sub-basins, which cover 19 percent of the region, are currently in very poor condition near the communities.
Agricultural land makes up around 10% of the total area, and it is mostly found near large rivers with moderate slopes. Irrigation is accessible along the Duhok stream, in Garmava, and in the Sindor village, which is the main wine-growing area, on moderate slopes as shown in figure (3), where vineyards are commonly cultivated, rainwater agriculture can be found [8].
The soil around the lake is generally unstructured and easily eroded when it rains. This creates silt issues and has a negative impact on vegetation degradation. Dam coverage due to illegal logging,    Table 1.

Water balance Parameters Assimilation
The water balance of the study area was calculated by using Lerner method, water surplus ratio from the yearly rainfall (Where the soil moisture considered = 0). The methodology used for the water balance in this research is well documented by [10] and [11]. As the following equation: P = Q + ETc + ΔS … …… (1) P: Precipitation (mm).
The excess of rainfall values over corrected evapotranspiration values during specified months of the year is described as water surplus like (Winter), whilst the excess of corrected evapotranspiration values over rainfall values during the remaining months of the year is defined as water deficit like summer [12] . They can have calculated with Actual Evapotranspiration (ETc) by using the following equation [13] : ETc: Actual Evapotranspiration (mm).

Rainfall
Annual rainfall has been fluctuating for the past 21 years ( Figure 5). The yearly rainfall pattern has been fluctuating for the previous 21 years, according to the participant during focus group talks and key informant interviews. Similar to this conclusion, rainfall variability was particularly noticeable in the years

Runoff
Model * This is true if P > 0.2S; otherwise, the P -Q data can be used to determine Q = 0 S. S is obtained from a mapping equation written in terms of in practice. increasing but the vice versa decreasing was appearing in the (2020-2021) for some months (show in figure   6). as the some, the annually average of runoff for (2020-2021) is below the annually average of runoff during all of the 5 years ago which is (32.38 mm) show in table (2). It indicates we cannot have harvested enough runoff water with in the Duhok dam basin due to lacking of main source in the region. Figure 6. The rainfall-runoff relationship

Evapotranspiration
The potential evapotranspiration is a combined term of evaporation and transpiration is defined as the total loss of water through evaporation and transpiration from the soil-plant system [15]. Thornthwaite suggested an equation to calculate the potential evapotranspiration after conducting several experiments on semi-arid climate types depending on the temperature only [16]. The evapotranspiration in the study area is calculated for each month as follows:

Groundwater recharge
All the water balance parameters affected on the groundwater recharge. Groundwater recharge depends on the amount of annual rainfall falling at the space area studied. to calculate the annual amount of water that recharges the groundwater, we use general equation of water balance (explained before). indicating that the discharge of the water within side the reservoir might not be stimulated through rainfall when you consider that it is able to be associated with the want of the water for irrigation [17] . The groundwater storage. This study is similar to the conclusion for the dry season. The change in storage significantly related to rainfall amount, but may be increasing in rainy season (September to April) inversely to dry season the groundwater storage is decreasing in (May to August). The reservoir's groundwater storage, on the other hand, is tied to the groundwater level. This discovery is crucial because it allows us to conclude that the groundwater level in the study region fluctuates as a result of rainfall rates but is not enhanced by irrigation or other sources of water, as shown in Figure (9).

Conclusion
The lake conceptual model was redefined and adjusted according to hydro-meteorological interpretation. The using of the water balance equation to assimilate groundwater recharge is a simple, quick, and effective way for interpreting hydrological studies in a given area, particularly when the region is experiencing a water crisis (2020-2021). Furthermore, the data reveal that a water shortage has occurred. Since the soil moisture content and groundwater storage as a percentage have been below average during (2020-2021). Using hydro-climatic characteristics (soil-water-balance approach), an aquifer recharge estimate of (-58.33 percent) of total rainfall was calculated. They permitted estimating a natural outflow of infiltrated water for soil moisture content (-8.3%) to the Duhok Dam Lake by specifying the volume by percent of the aquifer. Nevertheless, while the model contained different assumptions and limits, these results should be interpreted with caution. Rather than validating the data, we are attempting to make use of it. The study's key limitations include how these projected recharge values relate to groundwater age dating and the validity of the storability values.

Declaration of Competing Interest:
The authors declares that they have no conflict of interest.