Fulfillment of Clean Water Needs in Tamangil Nuhuten Village with Addition of New Spring

Thus the water needs of the Tamangil Nuhuten Village community can be fulfilled until 2031.


Introduction
Indonesia is one of Southeast Asia's largest archipelagic countries with up to 17,500 islands [1]. Supplying clean water in archipelagic areas needs special attention because people on small islands have difficulty accessing clean water due to limited supply [2]. According to the 2018 report by the National Development Planning Agency (BAPPENAS) of the Republic of Indonesia, around 72 million Indonesians have difficulty accessing clean water, especially in rural communities. [3]. The seventh target of the Millennium Development Goals (MDGs) is to ensure environmental sustainability, including household access to proper sanitation facilities [4].
Tamangil Nuhuten is one of the villages in the south of Kei Besar District, Southeast Maluku, which has not yet received clean water services and only depends on the Wiak spring.
Tamangil Nuhuten Village has an area of ± 4.99 km2, with a population of 883 people.
Currently, the Tamangil Nuhuten Village community is facing difficulty obtaining clean water, especially during the dry season. This is caused by a very small water debit in the existing springs during the dry season. Groundwater sources are very difficult to obtain because they are located very deep, and the condition of the soil layer is in the form of coral rocks. In addition, drought will likely hit Tamangil Nuhuten Village in the future. The low availability of clean water can be a risk factor for several diseases, such as common stomach aches, diarrhea, typhus, intestinal worms, dysentery, and urinary tract infections. [5].
The provision of clean water is considered capable of reducing 25-27% of disease.
Water quality can also reduce disease by 17% to 42%, while sanitation can achieve a risk reduction of 22-37%. [2]. Available clean water in adequate amounts will be able to support the level of productivity. Thus, it can improve public welfare [6] [7]. Efforts to meet the need for clean water can be made in various ways, such as purification equipment [8], rainwater harvesting [9] [10], and utilizing springs such as groundwater, rivers, lakes, and reservoirs [11].
In addition, coastal communities can desalinate seawater using a reverse osmosis system [12] and evaporation [13]. Each topography of an area has its way of meeting its clean water needs.
As in Bogori Village, West Kalimantan, meeting the need for clean water is done by constructing a piping system [14]. In addition, in Oenoni 1 Village, Kupang Regency, the need for clean water cannot be fulfilled because the discharge of the water source is very small compared to the need. [15]. Many studies have been conducted, but most are limited to studying the need for and availability of clean water. Therefore it is necessary to have research that reveals the efforts made to increase the availability of clean water so that the need is fulfilled.
This research aims to analyze the need and availability of clean water in Tamangil Nuhuten Village. From this, it can be seen whether the village can meet the need for clean water in the future. If not, efforts will be made to meet water needs. So that with these efforts, it is hoped that the village community will be able to fulfill their clean water needs in the future.

Research Method
The research was conducted in Tamangil Nuhuten Village, Kei Besar Selatan, Southeast Maluku, with coordinates5°49'37.49" " S132°54'13.04" " E. The research was conducted by taking primary data in water discharge at water sources, while secondary data was in the form of water consumption, population numbers, and water discharge. The research begins with projecting the number of residents. Then do the calculation of domestic and nondomestic clean water needs. After that, a water balance analysis was carried out.

Projection on the Number of Population
Projection number of population in the future could be used other methods like Arithmetic Method [16], Geometric method [17], Least Square Method [18], and Exponential Method [19].
Method selection is determined based on the method that has the highest correlation value. To determine the selection of projection method on the growth of the population, it is used the correlation method uses the following equation [20] (1): Where r is the correlation value (0 -1), n is the amount of data, and x y is the variable. The number on the correlation value (r) shows the closeness of the relationship between the two variables tested, namely population and time (year) [21]. If the correlation number gets closer to 1, then there is a stronger correlation between both variables, which means that the population changes as the year increases.

Calculation Water Needs
The calculation of water needs is based on population growth [18]. Meanwhile, water consumption for household needs (domestic) is 120 l/person/day, and for public facilities (nondomestic) is 30 l/person/day. The service coverage is assumed to increase by 5% every year, with a baseline in 2022 of 25%. The amount of water demand is obtained from the number of users served multiplied by the consumption of water needs.

Calculation Water Supply
To find out water availability, namely by measuring the discharge available in the spring. The amount of discharge is obtained from the flow rate formula Q = V x A (m3/second) [22], where V is the flow velocity (m/second) and A is the cross-sectional area (m2). The experiment was carried out 5 times at 3 different heights, namely 1/3h, 1/2h, and 3/4h from the water level. This measurement is used to validate whether the spring water discharge at RISPAM.

Water Balance Analysis
Water balance analysis is carried out by comparing water needs and water availability for the next 10 years so that it can be known in which year is experiencing a shortage or excess.
years of water shortage, it can be determined when to fulfill the deficiencies [23]. It is hoped that by looking at the results of the water balance all raw water needs can be provided.

Projection on Number of Population
Projection on the number of population until the next 10 years, namely 2022 to 2031, uses data on the number of population taken from the Tamangil village for the last 4 (four) years, as seen in Table 1. Source: BPS Southeast Maluku Regency [24] Correlation calculation results using the following arithmetic Method is 0.001; the geometric method is 0.730; Least Square Method is 0.739; and Exponential Method is 0.730.
Among these methods, the one with the highest correlation value is the Least Square method.,  Table 2.

Clean Water Needs
Calculation of the need for clean water is based on domestic and non-domestic.

a. Domestic Clean Water Needs
The calculation of domestic clean water needs in the next ten years is presented in Table 3. Table 3. Water Needs for Household (Domestic).

Source: Analysis (2022).
From Table 3, it can be seen that for 10 years, water needs for household connections have increased 5 times, from 0.3 liters / second to 1.6 liters /second.

b. Non-Domestic Clean Water Needs
The results of the calculation of water needs for public facilities can be seen in Table 4. (Domestic) and public facilities (Non-Domestic) water needs, the total water needs in Tamangil Nuhuten Village can be calculated for each year as follows: From Table 5. it can be seen that the amount of water demand until 2031 is total water requirement is 2 liters/second.

Clean Water Supply
To determine the water supply, it is by making measurements on the available debit in the Wiak Springs. A discharge of 1.2 l/sec was obtained based on the manual measurements results. However, this measurement is only done at one time, while to determine the debit of the Wiak spring in one year, data from RISPAM is used as follows.

Evaluation of Clean Water
Water balance analysis is used to evaluate whether the existing clean water supply will be able to meet future needs. The calculation results show that the water supply is 1.06 liters/second, and the total water requirement is 2.01 liters/second, so there is still a shortage of 0,949 liters/second. So, it can be concluded that the current clean water supply cannot meet the needs of clean water until 2031.

Addition Water Source
Seeing that Tamangil Nuhuten village cannot meet its water needs, what can be done is to add a water source near the village, namely the Baluruk spring, even though it is located farther from the Wiak spring. Therefore, it is necessary to study the Baluruk Spring before it is utilized as an additional source of raw water.

Water Debit
Measurement of the discharge of the Baluruk spring is presented in the table below.

Quality of Baluruk Spring
Based on RISPAM data by Maluku province in 2021, it was described that the quality of Baluruk spring met the class-1 Quality standards (standard spring for drinking water). For the quality of the Baluruk spring, it can be seen in Table 10.  Table 10. in the laboratory results, The value of all parameters is below the maximum limit, so the water is in a safe condition for use.

Location and Planning of Clean Water Distribution System
The position of the Village and Springs, along with the Planning for the primary water network system, can be seen in Figure 1.  Water from the Baluruk Spring (220 MASL) is first collected in a water reservoir to reduce sediment content. For the transmission pipe from the source to the reservoir, two pieces of 6inch PVC pipes are estimated to be capable of flowing a discharge of 83 liters per second. The water reservoir is located near the village with an elevation (115 MASL) and is 1.3 km from the spring, so there is a slope of 0.0766. Two water reservoirs are used to maintain the continuity of the water supply if a problem occurs so that the water can continue to flow. Each water reservoir is 4m x 6m x 3m with a total volume capacity of 144 m3 equipped with a control valve. The distance from the water reservoir to Tamangil Nuhuten Village is 500 meters, and one 4-inch distribution pipe is used. The village elevation ranges from 10 -50 MASL, so there is a difference of 65m from the water reservoir. This height difference is sufficient to provide energy to distribute water to the village without a pump graphically.

Conclusion
The total water demand in Tamangil Nuhuten Village in 2031 is 2.01 liters/second.
The village's clean water supply from the Wiak spring has a debit of 1.06 liters/second, so it is insufficient to meet water needs. The Baluruk spring can provide a discharge of 83,3 liters/second with relatively stable conditions throughout the year and meets the quality of clean water. Tamangil Nuhuten Village can take clean water from the Baluruk spring by building two water reservoirs to reduce the sediment content with dimensions of 4m x 6m x 3m placed 500m from the village. As well as used two 6-inch pipes for transmission pipes and one 4-inch pipe for distribution. With this, the water needs of the Tamangil Nuhuten Village community can be met until 2031.

Acknowledgment
This article is part of a Final Project in civil Engineering of the Engineering Faculty.
The author expressed his gratitude to the supervisor, Dean, and colleagues who helped complete this Final Project.