The priority of each ditch was determined by the district courts based upon the date the ditches were constructed and the water placed to beneficial use. The statute as passed by the legislature in 1879 did not provide for stream measurement.

The Office of the State Engineer was created in 1881. The primary responsibility of the State Engineer was to measure the water in each stream from which water was diverted for irrigation, starting with those mostly used for irrigation. Three water divisions were created, made up of water districts located within the South Platte, the Arkansas, and the Rio Grande basins. Within six years, each of the remaining four water divisions as they exist today were created. In 1887, the state created a Superintendent of irrigation - who is known today as the Division Engineer - to supervise Water Commissioners within each division.

By the beginning of the 1890's, many stream systems were over-appropriated. Ditch companies were actively constructing reservoirs to store winter flows and spring runoff. In addition, new sources of water were being pursued, which included trans-mountain diversions and pumping of ground water. Changes of water rights, exchanges, transfer of water rights and "loan statutes" were issues that had to be addressed by the office of the State Engineer by the turn of the century.

In 1899, the State Engineer was given the responsibility of approving all plans and specifications for dams designed over ten feet in height and covering more than twenty acres, or having a capacity of more than 1,721 acre-feet. In addition, the statures required that the construction had to be approved by the State Engineer. That same year the State Engineer was given authority to have water levels lowered in any reservoirs that were deemed unsafe.

Prior to 1957, no permit was required to construct a well. Ground water was not managed or allocated by the State, even though some of the earliest State Engineers expressed concerns about the impact alluvial wells might have on surface water rights. The Colorado Ground Water Law of 1957 required a permit from the State Engineer as a prerequisite to drilling a new well and obtaining a new ground water right. The law also made provisions for the registration of existing wells. The act also created the Ground Water Commission that was to identify districts where the rate of withdrawal from an aquifer exceeded the rate of recharge.

The Colorado Ground Water Management Act of 1965 provided for the formation of management districts which were empowered to regulate the spacing of wells in designated basins and set limits on production rates to minimize the lowering of water tables.

Also in 1965, statutes were passed that directed the State Engineer to administer the laws of the State relative to the distribution of the surface waters to include underground waters tributary thereto, in accordance with the prior appropriation doctrine. Subsequent findings of the Colorado Supreme Court found that regulation of tributary wells - in order to protect senior surface water rights - was constitutional. In addition, the court directed the State Engineer to promulgate rules and regulations that would maximize the beneficial use of ground water while preventing injury to senior water rights.

In response to the Supreme Court's findings regarding tributary wells and surface water, the Water Rights Determination and Administration Act of 1969 was passed. Besides changing the name of the State Engineer's Office to the Division of Water Resources, the act required that surface and ground water rights be administered together. Ground water rights were required to be adjudicated in order to protect their priority. Plans for Augmentation were also allowed to mitigate material injury to senior vested water rights.

During the mid-1980's, new legislation was enacted concerning non-tributary and not non-tributary ground water and the permitting requirements that the Division of Water Resources must utilize in managing these resources. Gravel pit legislation was also enacted which required owners of any gravel pit constructed after December 31, 1980, to obtain well permits and a court approved Plan for Augmentation plan of Substitute Supply to replace the evaporation losses that resulted from exposure of ground water. The State Engineer was given authority to promulgate rules and regulations regarding water quality for well construction, exchanges and substitute water supply plans. These rules and regulations were established in 1992.

The Division of Water Resources and the State Engineers are finding administration of water rights to be ever increasing in its complexity. Basin of origin issues, reserved rights, wetlands, endangered species recovery and interstate water issues are all new pressures on an already limited water supply. The State Engineer and the Division of Water Resources of the 21st century are committed to efficiently meeting these challenges of the future.