Editing Hydromanagement in Ancient India (section)

=== '''Pre-Harappan Beginnings: An Overview of Neolithic Mehrgrah Culture''' ===
The Neolithic era ranged from c. 7000 BC to c. 3000 BCE or later in the Indian subcontinent. The well-established Neolithic period is illustrated by advanced pottery, an agro-pastoral culture, population growth, geographical extension, and innovation in technologies such as the use of gold, seals, glazed steatite, beads, and a water irrigation system. The advanced plumbing and sewer systems were also developed by early engineers and reached their peak during the Harappan era.

One of the earliest examples of neolithic and pre-Harappan hydromanagement can be found in the sites of Mehrgarh culture, which was established on the hill slopes as well as the plain strips of hills or fans in the arid-to-semiarid region of Balochistan with scarcity of water for their survival and agriculture fields. They introduced the gabarbands and checkdams to store the rainwater from open areas, and the khushkaba and sailaba storage systems to store rainwater from the seasonal river in the valleys and use it for their survival. Due to mud-constructed walls and earth dug drains, archeologists know very little about the sanitation and wastewater technologies of Mehrgarh due to harsh weather conditions. However, the remains at Kalli Gull Muhammad and Bolan Pass, Baluchistan, indicate that they have a main drain at the sides of their residences and that the rainwater falls down to it directly from the roofs and houses. The construction of houses in a grid system reveals that there was a common wall between two houses, and in the middle and in the corner of the house, there was a toilet and a bath. Outside the constructed area, there was a check dam for the storage of rainwater with an open inlet drain from the slope or elevated areas. The check dams were used as swimming pools and also for domestic water use. A common well also existed in Kalli Gull Muhammad, as well as Bolan Pass, with spring water in nearby valleys. This evidence indicates that they had common use of wells as well as spring water, which shows their unity and coordination with one another. The Mehrgarh people were developing the concept of a swimming pool or groundwater logging system. In the northwestern part of Kalli Gull Muhammad remains, there is a square-shaped pool or water tank on the ground with an open area around it. This swimming pool is some distance from the water check dam of the settlement, with an inlet and an outlet on the eastern and western sides with compact wall stone. Furthermore, the evidence of gabarbands in Tung Valley, Sind, also represents the waterlogging technology of the Mehrgarh people for agricultural purposes, the latter of which might have been converted into check dams as well as hydro-dam technology. The "great bath" owes, without doubt, a debt to the proto-tanks of Mehrgarh. In Neolithic Mehrgarh, the water wells and tanks seem to be on one side of the village or constructive area. There is no evidence of individual wells, water tanks, or storage systems. The main drain seems to be around the constructed area, with some link drains from the houses. No doubt, the water management system of the Mehrgarh civilization was not well developed, but it provides a clue for the promotion of water technology in the future. Resultantly, the water treatment and sewage system of the Harappan civilization were more advanced compared to the Neolithic era. The Mehrgarh village of Kalli Gull Muhammad, as well as Bolan Pass remains, indicate that they had a well and water tank, as well as baths. The well and water tank were common entities to facilitate the whole village. In the houses, between bedrooms, there are small square-shaped units in the form of a row, which shows that these were the baths as well as the toilets, which exist in almost all houses ((Khan, Yilmaz, Valipour, Angelakis, 2021)<sup>17</sup>.

Generally, the Neolithic Mehrgarh is known as the village system, with some compact and dispersed house systems. The drain around the village and the waterlogging check dams indicate that they were aware of the drainage system but were not well developed technologically. It is hard to observe the well-developed drainage system in the Neolithic period, as most of these sites exist in arid areas. The remains of the gabarbands, check dams, khushkaba, and sailaba systems in the nearby valleys of the Mehrgarh settlements prove that they had a well canal and irrigation system in the entire area for the cultivation of food and cash crops (cotton, burnt rice, wheat, and barley). Because, from each gabarband, check dam, khushkaba, and sailaba, there are a number of outlet channels that represent a clue of canals to the agricultural fields near the archaeological sites of Bolan Pass, as well as Kalli Gull Muhammad. The Mehrgarh civilization was flourishing in the hilly areas and a plain strip of mountains in Balochistan during ca. 7000–2500 BC, with major archeological sites such as Kalli Gull Muhammad, Bolan Pass, Charsadda, Takht Bhai, and Udigram having complete knowledge of sanitation, canal systems, the construction of water dams, wells, and water tanks, agriculture, trade, sewers, and business systems. The developed structure of that culture then appeared in the shape of the Harappan Civilization, under which the application of neolithic hydrological management techniques reached its culmination.