The Lugeon Test: Methodology, Interpretation, and Applications in Geotechnical Engineering

 Irrigation systems have a rich and extensive history, demonstrating a long-standing practice and continuous evolution across various civilizations and time periods. From ancient methods to modern automation, the development of these systems reflects humanity's ongoing efforts to manage water resources for agriculture and other needs.

Here are key historical examples and evolutionary milestones:

• Prehistoric and Ancient Civilizations (6th Millennium BCE onwards):

  • The earliest known evidence of irrigation dates back to the 6th millennium BCE in Khuzistan, Iran.
  • The site of Choga Mami, located on the Iraq-Iran border, provides the earliest indication of canal irrigation in operation around 6000 BCE.
  • The Indus Valley Civilization (around 4500 BCE) developed sophisticated irrigation and water-storage systems, including artificial reservoirs at Girnar (3000 BCE) and an early canal irrigation system (c. 2600 BCE), supporting extensive agriculture.
  • In Mesopotamia, farmers practiced perennial irrigation using small channels from at least the third-millennium BCE.
  • Ancient Egyptians employed basin irrigation, utilizing the Nile's annual flooding. Pharaoh Amenemhet III, around 1800 BCE, famously used the natural lake of the Faiyum Oasis as a reservoir to store surplus water for dry seasons.
  • The Ancient Nubians developed a form of irrigation using a waterwheel-like device called a sakia, with irrigation beginning between the third and second millennia BCE. Irrigation also reached sub-Saharan Africa's Niger River region by the first or second millennium BCE.
  • Evidence of terrace irrigation can be found in pre-Columbian America, early Syria, India, and China. In Peru's Zana Valley, irrigation canals dating from the 4th millennium BCE, 3rd millennium BCE, and 9th century CE have been discovered, with traces of a possible 5th millennium BCE canal.
  • The Qanats, an ancient Persian (Iran) innovation from around 800 BCE, are a network of vertical wells and sloping tunnels tapping groundwater, still in use today across Asia, the Middle East, and North Africa.
  • The noria, a water wheel powered by stream flow or animals, was introduced by Roman settlers in North Africa around 800 BCE.
  • Ancient Sri Lanka's irrigation works, starting around 300 BCE under King Pandukabhaya, included underground canals and completely artificial reservoirs, many of which remain intact.
  • In China, significant hydraulic engineering dates back to the 6th and 5th centuries BCE. The Dujiangyan Irrigation System was built in 256 BCE in Sichuan. By the 2nd century CE, the Han dynasty utilized chain pumps for irrigation.
  • Korea saw the invention of the world's first rain gauge, uryanggye, in 1441 by Jang Yeong-sil, integrated into a nationwide system to measure rainfall for agricultural planning.
  • In North America, the earliest agricultural irrigation canal system dates to between 1200 BCE and 800 BCE in Arizona. The Hohokam culture (7th-14th centuries CE) built extensive, complex irrigation networks using simple excavation tools.

• Medieval and Colonial Eras:

  • In medieval India, Sultanate rulers like Firoz Shah Tughlaq (1309–1388) developed extensive canal irrigation systems. These were continued by subsequent Mughal rulers.
  • The British colonial government in India built significant canal networks, often on existing medieval systems, by 1940. Examples include the Ganges Canal, which stretched 350 miles. By 1900, irrigated land in British India had increased eightfold to 13 million hectares. However, much of the added capacity during this era was from manually operated groundwater wells and tanks.

• 20th Century and Modernization:

  • The scale of global irrigation increased dramatically in the 20th century, from 8 million hectares in 1800 to 94 million in 1950, and 235 million in 1990. By 1990, 30% of global food production came from irrigated land. By 2021, this reached 352 million hectares, more than double the 1960s area.
  • In the American West, irrigated land grew substantially from 1880 to 1900. While wind-powered pumps were initially used, the mid-1930s saw the advent of gas-powered pumps for deeper wells. The introduction of center-pivot sprinklers after World War II significantly eased irrigation.
  • In Egypt, modern irrigation began in the mid-1800s with irrigation barrages in the lower Nile to support cotton production, a shift from traditional basin irrigation. The British later intensified this with structures like the Delta Barrage and the first Aswan Dam.
  • Prior to 1990, computerized automation in canal systems was limited. Old designs relied on methods like radial gates and manual orifice flow control (U.S. Bureau of Reclamation designs) or hydraulic gates like AMIL, AVIS, AVIO, and MIXTE, or long-crested weirs (French hydraulic designs) for water level control.
  • The 1960s and 1970s saw the use of computers to simulate open canal flow, advancing canal automation studies. In the late 1980s and early 1990s, the focus shifted to technical interventions like improved water level and flow control.
  • The Rangitata Diversion Race in New Zealand, constructed between 1937 and 1944, was manually operated initially but later modernized with SCADA systems and automated FlumeGates.
  • The implementation of SCADA software for managing canal systems emerged as a significant advancement, requiring training for operators.
  • Modernization efforts now involve various technical, managerial, and organizational upgrades to optimize resource utilization and water delivery service. This often includes installing solar-powered automated gates, establishing hybrid wireless data communication networks with main SCADA centers, data concentrator stations, and slave stations, and utilizing Geographic Information System (GIS) based Irrigation Network Management Information System (INMIS) for demand aggregation and scheduling. These integrated systems aim to provide precise control over water flow, even in the absence of human operators.