Prediction for Natural Recharging In Langat Basin and Ukm Campus as Case Study

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Prediction for Natural Recharging In Langat Basin and Ukm Campus as Case Study 1 Mohaad Fawzi Al Ajlouni, 2 Rakmi Abd Rahman, 3 Abdul Ghani Rafek, 4 Mazlin Mokhtar, 5 Noor Ezlin Ahmad Basri 1, 5 Department of Civil and Structural Engineering 2 Department of Chemical and Process 3 Center of Environmental Sciences and Natural Resources Studies 4 Institute for Environment and Development (LESTARI) Universiti Kebangsaan Malaysia 43600Bangi, Selangor, Malaysia ABSTRACT Various water budget elements such as water supply to the, ground water recharge, and change in storage are predicted by Water Budget Method for a period of 2.5 years. The predicted water budget elements are evaluated by UKM Meteorological station data. The results show that the modelling undertaken is on the flow of the water and calculation of the water balance for the constructed wetlands using the water budget equation in order to determine the potential underground water resources of the UKM Bangi, Campus. The modeling will be based on the known geology of the area from previous research and Water availability from the known sources, e.g. Engineering and Golf lakes, which are being used as alternative water sources for the Campus. The volume of water that can be held by the UKM aquifer is about 1.4 million m 3, which agrees with the estimate by JICA (2002) for the Langat river basin, that the recharging rate is 4.8% of the annual rainfall, from this study the recharging rate is 5% of the annual rainfall. The close approximation of the results for Langat Basin and UKM campus supports the contention that the UKM catchment is just a sub-catchment of the Langat River basin and should have similar properties. Keywords: Water Budget Prediction and Modelling, UKM Campus as Sub River Basin Case Study 1. INTRODUCTION Malaysia receives an average annual rainfall of 3000 ; Malaysia is rich in water resources, whose development has been the basis for the socio Economic development of the country (Malaysia s Water Vision, 2001), Predicting the Natural Recharging In the UKM Bangi Campus, and to construct the Aquifer storage Modeling by Using Visual MODFLOW Pro V 4.2 (Waterloo Hydrogeology,2004),to model the groundwater flow under The UKM Campus, also under Langat Basin, by taking into consideration the special conditions and boundaries for every Case. This study focused on the importance of Integrated Water Resources Management (IWRM) research, its goals and case study in UKM campus as a sub Langat River Basin, IWRM includes surface and ground Water Management, capacity scales, decision, tools, sociology economics, Human health, and ecology, zooms in Predicting and Modeling. In Malaysia the public water supply demand is growing (Water Resources Management in Malaysia, 2004). This is a problem because the groundwater supply is already under stress, In order to meet this higher demand new techniques are being researched. This study started in the natural recharging under the UKM campus as case study of the Langat sub-river basin, studying the water storage volume to determine later the aquifer capacity and the scenario of the artificial recharging to the aquifers under the UKM campus and under the Langat river basin, applying ASR is enhancing the groundwater quality and quantity, its anew develop method conserve our water resources 2. PROBLEM STATEMENT Some of the related water problems in Malaysia are; Water flooding problems: water should be stored during flooding. Water losses, and high water demand in certain regions, Water for Drinking, Water for irrigation, Water for industries. Increase in demand drinking water due to increasing population Ration. 3. OBJECTIVES OF THE STUDY In this research, the main aspects of the integrated water resources management (IWRM) was being investigated were the Water Resources Management, Runoff Storage, Wetlands Modeling, and Aquifer Natural Recharging (ANR). The objectives of the project were to evaluate groundwater potential at Langat basin by constructing the 3-D mathematical model in order to estimate the safe yield by considering potential impacts of water abstractions. The aims of the project were: (i) To determine the parameters associated with surface runoff, wetlands, infiltration, and 93

(ii) storm water effluents and aquifer storage. To develop a hydrological model for water resources components watershed scales. Additional classifications also exist. Within each method, a number of estimation techniques were available (Scanlon, Healy, and Cook, 2002). So our Methodology based on the following: (iii) 4. RELATED WORKS To determine the maximum recharging and withdrawal rates for a given aquifer used for natural recharging with UKM aquifer as a case study. Integrated Water Resources Management (IWRM) is an approach towards integrating and effectively coordinating policies, programs and practices addressing water-related issues, which takes into consideration the various aspects of socio-economic development and the conservation of the environment (Shahrizaila Abdullah, 1999). Water resources development has been a catalyst for socioeconomic development of the country (Raja Dato Zaharaton, 2004). The need for managing water resources is very important as the crisis is not about having too little water to satisfy our needs. It is a crisis of managing water so badly that billions of people and the environment suffer badly. The management of water resources should be based on sound policies and strengthened institutional arrangements (Raja Dato Zaharaton 2004).Aquifer recharge and change in subsurface storage include the result of the natural groundwater recharge-discharge regime and artificially managed processes. Thus subsurface storage is induced by any recharge, either natural or artificial (Albert Tuinhof et al.2003). 5. PROPOSED METHODOLOGY OF SOLUTION (i) (ii) (iii) (iv) (v) Meteorological Stations Data. Wetland (constructed, created). Pumping wells UKM1, 4, 4A, 5,5A. Topographical maps (GIS), and (GPS) readings and corrections. Using water Budget method and advanced prediction for UKM Site for natural recharging. A number of methods were used to estimate recharge. These can be classified as (1) direct or indirect; (2) physical, chemical, or isotopic; (3) methods based on the analysis of inflow, outflow, or aquifer response; (4) methods based on the unsaturated or saturated zones; and (5) methods based on numerical modeling of ground-water flow, soil-water flow, both soil- and ground-water flows, or modeling of the hydrologic balance at plot, field, or (i) (ii) (iii) (iv) Materials and methods depend on Data Collection from the previous studies in the same field such as Estimation of groundwater recharge using Tank model (JICA 2002). Study of the water balance in study area; make Surveys on the downstream lakes, Upstream, and other open water bodies In UKM site, and all water bodies in UKM Campus. Using the water Budget Equations for the Constructed wetlands To Construct a conceptual model in order to design and to set up boundary conditions of the mathematical model. Develop special model to estimate the natural recharging in UKM campus, and compare these results with results from similar models. 5.1 DATA COLLECTION 5.1.1 Primary Data Collection Wetland, Depth, Length, Width, Vegetation, Soil, Elevation. Water resources need to be monitored generally include quantity of water Bodies in UKM campus Wetlands (Engineering Lake, Golf Lake), Soil Investigation by researching many conducted boreholes, Pumping wells Characteristics,Lithology, Drawdown Carve, Pumping test, Aquifer Characteristics, Wetland Classification, water quantity and Resources availability, the comprehensive information and data collected during this phase, the data should evaluate with the water quality standard and country assessment criteria. 5.1.2 Secondary Data Collection (i) Meteorological Stations Regarding to the meteorological station data that s available on the main site and related to our methodology we can take the updated information that were available, evaporation, evapotranspiration, humidity, and wind speed The most important parameters that given by tow meteorological station in UKM Campus are: the annual rainfall and annual evaporation for the last four years (2003-2006) as shown in the Table.1 below: 94

Table 1 Annual water parameters Estimated by Tow Meteorological Stations in UKM Campus (2003-2005) Year Annual rainfall Annual pan evaporation A B C=(B*0.8) 2003 2613.5 963.2 770.6 2004 1937.9 1161.1 928.88 2005 1895.4 1284.2 1027.36 2006 2149 1136 908.8 Average 2148.9 1136.2 908.95 % 100 52.9 42.3 Estimated Annual pan evaporation 80% of Source: UKM Meteorological stations.2006 (ii) Aquifer Characteristics a. Aquifer Porosity From the pumping test, water entering an unconfined or confined well, will stand at a particular level. This level is often termed as the hydraulic head and is actually the sum of three components - the pressure head, elevation head and velocity head. The velocity head is often disregarded because ground water movement in most cases is relatively slow. In practical applications, Depth to ground water measurement is obtained and subtracted from the top of the well casing elevation to measure total head. Aquifer soil type clayey, quartz fractured. Aquifer depth =b=100 m and aquifer porosity=n =0.43 The drilling works indicates 1 st crack zone in phylite occur at the depth of 33 m to 35 m deep, spits well water approximately 2.73m3/hr. (600galllons/hr).The fracture zone at 43m to 45 deep produces approximately 6.83m 3 /hr (1500 gallon/hr). As shown on the following Tables 2, 3, 4, 5, 6: Table 2 Wells Pumping Test and Wells Elevation in UKM Campus Well No UKM1 UKM5 UKM4A UKM5A Year m 3 /hr m 3 /hr m 3 /hr m 3 /hr 30-31/7/2005 4,55 17-18/9/2005 6,83 8-9/10/2005 4,55 14-15/10/2005 9.1 Wells ASE m 51 m 37 m 50 m 36 m Source: JPP UKM 2006 95

Layer No Depth (m) Table 3 Wells Pumping Test at UKM W 4 -Hydraulic Parameters Thick b(m) Lethiological Description 1 3 3 Clayey 2 6 3 Clayey KH(ms -1 ) KV(ms -1 ) KH /KV Ss m -1 3 9 3 Clayey sand 6.00e-5 6.00e-6 10 3.7e- 5 4 16 6 Sandy Clay 1.00e-8 7.00e-9 1.43 3.7e- 5 5 18 2 weathered 6 26 8 Clayey silt 1.00e-7 600e-8 1.67 6e-6 0.01 7 32 6 Quartz 8 103 71 Crack Zone Sy 0.15 0.01 Layer No Depth (m) Source: JPP UKM 2005 Table 4 Wells Pumping Test at UKM W 1 -Hydraulic Parameters Thick b(m) Lethiological Description 1 3 3 Dark Clayey 2 9 6 Clay 3 18 9 Greyish Clayey &weathered Quartz 4 24 6 Weathered phylite &Quartz vein KH(ms -1 ) KV(ms -1 ) KH /KV Ss m -1 6.00e-5 6.00e-6 10 3.7e- 5 1.00e-8 7.00e-9 1.43 3.7e- 5 5 45 21 Fresh phylite &Quartz vein(crack Zone) 6 70 25 Fresh Tuff 1.00e-7 600e-8 1.67 6e-6 0.01 7 100 30 Fresh phylite &Quartz vein(crack zone) Sy 0.15 0.01 Source: JPP UKM 2005. 96

Table 5: Wells Pumping Test at UKM W5A -Hydraulic Parameters Layer No Depth (m) Thick b(m) Lethiological Description KH(ms -1 ) KV(ms -1 ) KH /KV Ss m -1 Sy 1 3 3 Clayey 2 9 6 Clayey 3 12 3 Clayey sand 6.00e-5 6.00e-6 10 3.7e-5 0.15 4 15 3 Sandy Clay 1.00e-8 7.00e-9 1.43 3.7e-5 0.01 5 18 2 weathered 6 22 4 Clayey silt 1.00e-7 600e-8 1.67 6e-6 0.01 7 27 5 Quartz 8 103 76 Crack Zone Layer No Source: JPP UKM 2005. TABLE 6 Wells Pumping Test at UKM W5A -Hydraulic Parameters Depth (m) Thick b(m) Lethiological Description 1 3 3 Clayey 2 6 3 Clayey KH(ms -1 ) KV(ms -1 ) KH /KV Ss m -1 3 9 3 Clayey sand 6.00e-5 6.00e-6 10 3.7e-5 0.15 4 16 6 Sandy Clay 1.00e-8 7.00e-9 1.43 3.7e-5 0.01 5 18 2 weathered 6 26 8 Clayey silt 1.00e-7 600e-8 1.67 6e-6 0.01 7 32 6 Quartz 8 39 7 Crack Zone 9 103 64 Crack Zone Sy Source: JPP UKM 2005. 5.2 Data Analyses There are many deferent types to analyze our collected Data but to compare our data and methods that used to analyze these data; I choose the following method in analyses to compare my result with the JICA Study Result, JICA 2002. This study used this method to analyze UKM and Langat Basin Data by: (i) Prediction by Using Water Budget (ii) Method for Natural Recharging. By using comprehensive information and data collected during UKM Surveys this study created special prediction model depend on the water budget equation and we use this prediction as an advanced model. 97

Figure 1 water budget prediction for constructed wetlands Source: Mohaad et al., 2006 6. RESULTS AND DISCUSSION Develop a new hydrological modeling Software to manage system component of the water resources budget for ASR, Wetland and to conform the integrated management for the water resources requirements, design appropriate wetland for runoff and storm water storage with flood control facility storage and aquifer storages, create suitable software for our model, that model is general model take in consideration all variables entering the water budget Equation,but the calculation of the infiltration and all of the equation variables is in special case for our general model take in the location as a metrological station in the location our team suggestion is to apply this modeling on overall Malaysia,because this model didn t need data from outside,the model give you the data which it is necessary to apply in the general equation to give us the result of the water Budget as Table7,8,9,10 as follows: Table 7: Average water balance in the UKM catchments area as sub Langat River Basin in 2003-2005 Year Annual rainfall Annual pan evaporation Annual Discharge Estimated Annual pan evaporation 80% of Annual ground water recharge Annual ground water recharge (x10 6 m 3 )Are a (10.963) km 2 million m 3 A B C=(B*0.8) D E=(A-C-D) F=Ex Area 2003 2613.5 963.2 770.6 1382.54 125.45 1.375 2004 1937.9 1161.1 928.88 1025.15 93.02 1.02 2005 1895.4 1284.2 1027.36 1002.67 90.98 0.997 average 2148.9 1136.2 908.95 1136.77 103.15 1.13 % 100 52.9 42.3 52.9 4.8 - Source: UKM Meteorological Stations.2006 98

Table 8: Water Balance for the Golf Lake GOLF LAKE m3/year Q in =3092644.8 Q p = 150430 Q R = 1504300 Q Go =4638675 Q E = 79534 Q storage = Q infiltration Q infiltration = 28874 Source: Mohaad et al., 2006 Table 9: Water Balance for the Engineering Lake ENGINEERING LAKE m3/year Q in = 173493 Q Go = 319912 Q storage = Q infiltration Q p = 68184 Q E = 36050 Q R = 121758 Q infiltration = 7474 Source: Mohaad et al, 2006 Table 10: Average Water Balances in the UKM Catchments area As Sub Langat Basin in 2003-2005 Q Type Q in Q out Q storage (m 3 /d) (m 3 /d) (m 3 / year) Q RAINFALL 64499.4 3744*365.25= 1367496 m3/year Q EVAPORATION 469.54 Q EVAPOTRNSPIRATIN 34841.33 Q RUNOFF 25444.5 Q INFILTRATION 3744 Q INFILTRATION 1367496 m 3 /year =5% from annual rainfall Source: Mohaad et al,. 2006 7. CONCLUSION For the aquifer storage and recovery the main important expected conclusion are: 1. The experiment is given us an overall understanding of the IWRM as a UKM Campus catchments level. 2. The water budget concepts which apply on the UKM site is special for our model and could be apply in similar boundaries which they poses same conditions. 3. The software for our program takes in consideration the wetland design criteria, and the catchments area design criteria. 4. Regarding to our aquifer properties, fractured aquifer, unconfined aquifer, but with systematic fractures that we apply our 99

research on it, the result of the aquifer storage and recovery volume of water and the recovery efficiency needs to microscopy studies for the fractured aquifers effective porosity, that will be future work, and the result still apply on this special limited scale (UKM Campus aquifers). TEAM S SUGGESTIONS AND FUTURE WORKS we suggest to build many wells in UKM site in many locations and monitoring the ground water level in these wells in order to increase the sufficient data on this site,cause we can benefit from this data for future studies especially for ASR concept, and to get the relation between the Water recharges quantity with its Quality and determines the stopping point of Discharging from the aquifers, and the future work will be the estimation of artificial recharging by Visual MODFLOW 4.2 in the Langat basin and UKM Campus As case study. REFERENCES [1] Department of Environment, 1999. Malaysia Environmental Quality Report. JICA.2002.TheStudy on the Sustainable Ground Water Resources and Environmental Management for the Langat Basin in Malaysia. [2] Malaysia s water vision, 2001. Global water partnership (GWP). Integrated Water Resources In Malaysia the Way Forward. [3] Raja Dato Zaharaton, Raja Zainal Abidin.2004.Water Resources Management, Asia Water Conference. [4] Shahrizaila Abdullah, 1999. Towards a Malaysian and global vision for water, life and the environment. Workshop on the sustainable management of water resources in Malaysia a review of practical options, Malaysia. [5] Scanlon, B.R., Healy, R.W., and Cook, P.G., 2002, choosing appropriate techniques for quantifying groundwater recharge: Hydrogeology Journal, v. 10, p. 18 39. [6] Tuinhof, A. et.al. 2003. Recharge enhancement and sub surface storage: a promising option to cope with increasing storage needs. Management of Aquifer Recharge, NCC-IAH publication no.4, 2003, Utrecht, The Netherlands [7] Water Resources Management in Malaysia, 2004.The Way Forward. Achieving World Class Water, KDN PP11720/9/2003 ISSN 0128-4347. Vol.22 100