[12/15/2022]
APPROPRIABLE DENVER BASIN WATER SUPPLY
The volume of water in storage in the Denver Basin aquifers beneath a parcel of land, exclusive of prior appropriated rights. The volume of appropriable water in storage is calculated based on overlying land area, aquifer saturated thickness, and the specific yield of the aquifer. Under Colorado law, 1/100th of the appropriable water in storage can be extracted on an average annual basis from each Denver Basin aquifer.
APPROPRIABLE TRIBUTARY WATER SUPPLY
The amount of water from either a stream or tributary groundwater source that can be appropriated under the Colorado Doctrine of Prior Appropriation and a Water Court decree can be obtained for such water supply.
AUGMENTATION PLAN
If a tributary or not-nontributary water right is sought to be appropriated, it is incumbent upon the applicant for these water rights to demonstrate non-injury to existing, vested senior water rights. If such analysis indicates that there is the potential for injury to existing vested senior water rights, an augmentation plan must be adjudicated in Water Court which defines the uses of the water sought in the appropriation, defines the extent of the injury that will occur due to this appropriation, and presents a plan that will fully mitigate injury to all existing vested senior water rights.
COLORADO SYSTEM OF WATER RIGHTS ADMINISTRATION
Colorado operates under a "first in time, first in right" water rights administration for tributary waters of the state. This means that the most senior tributary water rights are wholly satisfied first, prior to any junior water rights diverting. If there is insufficient water to meet the water demands of all of the water rights, some water rights will be deemed "out of priority," and will not be allowed to divert any water until sufficient supply is available for all rights senior to that right.
CONJUNCTIVE USE SUPPLY
A supply that combines the use of both renewable and non-renewable water supplies to reduce the potential for adverse physical, economical, and environmental effects caused by the failure of a single-source water supply. A conjunctive use supply shall include at least 50% renewable water.
DAKOTA SANDSTONE FORMATION
An area of the County that is located in the water supply zones between the Pike-Rampart and the Denver Basin. This area consists of older sedimentary formations that generally underlie the Denver Basin aquifers but are uplifted to the surface in this area and are characterized by pronounced hogback and red sandstone features. Water supplies obtainable from these older sedimentary formations are quite limited and closely resemble the water availability of Margin A of the Denver Basin. Therefore, this area is considered part of Margin A for the purposes of the regulations set forth in the Water Supply Overlay District.
DENVER BASIN
A large groundwater basin of sedimentary rock formations containing four principal aquifers, the Dawson, Denver, Arapahoe and Laramie-Fox Hills. This water basin extends from Greeley on the north to Colorado Springs on the south, Limon on the east to the foothills on the west. Groundwater contained within the Denver Basin aquifers is considered to be either nontributary or not-nontributary water under the Colorado Water Rights System.
1.
CENTRAL BASIN
The area comprising most of the eastern half of Douglas County that is underlain by the Denver Basin. This is the area of the Denver Basin where the four principal aquifers are present and where the aquifers are located at, or near, the base of the bowl-shaped Denver Basin. Due to the presence of the four principal aquifers and the relative location in the Central Basin, water supplies developed in this zone can provide the minimum 100-year useful life.
2.
MARGIN B
An area west of the Central Basin of the Denver Basin, where aquifer elevations are comparable in relation to the Central Basin of the Denver Basin. Water supply availability in this zone may not provide a minimum 100-year useful life.
3.
MARGIN A
An area west of Margin B of the Denver Basin, which is characterized by the westernmost extent of the Denver Basin. Due to the outcrop of the Denver Basin in this area and the relative elevation of the Denver Basin aquifers compared to the remainder of the Basin, water supplies in this zone may not provide a minimum 100-year useful life.
DISTRICT
A special district currently offering water service, organized or validated pursuant to the Special District Act, § 32-1-101 et seq., C.R.S.; or a non-specified governmental entity including, but not limited to, municipalities, authorities, and public improvement districts, as well as private water companies.
DYNAMIC ANALYSIS
Water supply availability and reliability evaluation required if an applicant wishes to use Denver Basin water in Margin A or more than 50% of the water supply available in Margin B, as estimated from the static analysis. This analysis requires the use of a model that accurately simulates the geologic and hydro geologic characteristics of the Denver Basin and how aquifer parameters and water levels will change over time. A dynamic analysis can evaluate long-term water supply availability and reliability because it simulates actual conditions and how they likely will change in the future, rather than assuming constant values for all time, as in the static analysis. This analysis is typically completed using a numerical groundwater model.
ESTABLISHED DISTRICT
A district currently offering water service and conforming to one or more of the following criteria:
1.
Organized or validated pursuant to the Special District Act, § 32-1-101 et seq., C.R.S., with a service plan or statement of purposes approved by Douglas County prior to August 12, 1998.
2.
Designated as such pursuant to § 1-1809A, herein.
3.
A Colorado municipality providing water service to a minimum population of 25,000 persons.
MINIMUM 100-YEAR USEFUL LIFE
A water supply that will reliably provide water for a minimum time frame of 100 years. The County policy to determine useful life requires a showing from both a static and dynamic basis that a proposed water supply will be viable for a minimum 100-year period. The static analysis would include evaluation of the volume of water that is appropriable for the proposed development. The dynamic analysis would evaluate whether the appropriable water supply is sustainable for 100 years, giving consideration to the location within the Basin, as well as impacts caused by both current and future pumping by others in the Basin.
NEW SPECIAL DISTRICT SERVICE PLAN
A document for the organization of a new special district as authorized by § 32-1-201 et seq., C.R.S. The service plan generally outlines the services a district will provide and provides a financial plan for the procurement of land and facilities that may be necessary to provide district services.
NON-RENEWABLE WATER
Water that is not annually recharged through the hydrologic cycle and development of the water resource relies upon drawing water principally from storage in an aquifer. This is also referred to as a "finite water supply."
NONRESIDENTIAL EQUIVALENT
The quantity of water necessary for light industrial or office uses which corresponds to the residential standard of 0.75 acre-feet per year. The nonresidential equivalent is equal to 0.75 acre-feet per year required for each 6,695 square feet of building space.
NONTRIBUTARY WATER
Waters of the Denver Basin that, when pumped, will not, within 100 years, affect the flow of any natural stream by greater than 1/10 of 1% of the annual pumping volume. This is a non-renewable water supply.
NOT-NONTRIBUTARY WATER
Waters of the Denver Basin that, when pumped will, within 100 years, affect the flow of a natural stream by greater than 1/10 of 1% of the annual pumping volume. Because the pumping of not-nontributary water will cause an impact to the surface stream system, an adjudicated plan for augmentation is required prior to the use of not-nontributary groundwater from the Denver Basin aquifers. This is a non-renewable water supply.
PIKE-RAMPART
The western portion of Douglas County that is characterized by the uplifted granitic mountains west of the Dakota Sandstone Formation and the Denver Basin, water supplies in this zone are primarily through fractures in the granitic and metamorphic rock. While this water is renewable, due to the relatively low permeability of these fractures, water supply availability is relatively limited in the Pike-Rampart.
RENEWABLE WATER
Water from a source that is recharged during one or more stages of the hydrologic cycle, such as streams, and alluvial aquifers associated with streams, so that the water supply is reliable over time, subject to physical supply and legal availability within the prior appropriation system.
REUSABLE WATER
Water either from fully-consumable tributary water rights or from the treatment of the portion of first-use Denver Basin aquifer water that is reusable to extinction. Reusable water can be part of a water rights portfolio, subject to a showing of its availability, reliability, and quality.
STATIC ANALYSIS
1.
Water supply availability evaluation required for proposed land uses that plan to use Denver Basin water in Margin B or in the Central Basin. This analysis is based on assumed constant values for the land area, aquifer specific yield and aquifer-saturated thickness. Aquifer specific yield and saturated thickness values are obtained from the Denver Basin Rules, promulgated by the Colorado State Engineer's Office, or, when available, from a decree from the water court or from geophysical logs of wells drilled on, or near, the subject property.
2.
Annual water supply availability is calculated by static analysis as: land area available for appropriation X aquifer specific yield X aquifer saturated thickness/100 years. A static analysis cannot evaluate the long-term reliability of a water supply.
TRIBUTARY WATER
Water contained within the surface stream systems, or in groundwater that is hydraulically connected to the stream system. Tributary waters are considered waters of the state, are available for appropriation through the Colorado Water Rights System, and are subject to the Colorado System of Water Rights Administration. Tributary water rights are based on the priority of the rights to the extent that they can be relied upon as a water supply and meet the minimum water supply criteria, herein. This is a renewable water supply.
WATER CONSERVATION PLAN
A description of implementation and enforcement efforts put forth to reduce water losses, waste, or use for both indoor and outdoor uses, dependent upon the land use application.
WATER PLAN
Documentation provided to Douglas County in support of a land use application which details:
1.
The source(s) of water to be supplied to meet the development demand.
2.
The water supply delivery system, including the structures to be used for the diversion or extraction of the water, the conveyance system, and the required storage facilities.
3.
Demonstration of the reliability of the water supply, both from a physical and legal supply perspective, and including all losses associated with the delivery and storage system to be used.
4.
Proof that the water supply is owned and can be used by the applicants for the purposes intended in the application.
5.
Proof that all necessary decrees, permits, and any other legal requirements are in place that allow the legal use of the water supply.
6.
The timing of the development demands through the build out of the project.
7.
Estimated demand of the development.
WATER SUPPLY
The legal and physical delivery of water service that is sufficient in terms of quantity, quality, and dependability to meet the demand of a proposed development.
WATER SUPPLY REPORT
1.
A report documenting the amount of water that can be supplied to the proposed development, containing the following:
A.
A summary or report of the water rights owned or controlled.
B.
A description of fully-executed contracts and/or IGAs with other water providers in which all of the terms and conditions of the contract and/or IGA have been satisfied, as demonstrated by a signed will-serve letter from the provider.
C.
The anticipated yield of these rights in both an average year and a dry year.
D.
The present demand and the anticipated demand on the supplier due to commitments for service entered into that are not yet supplied.
E.
The amount of uncommitted firm supply available for future commitment and development.
F.
A summary of what water rights the applicant will convey to a district and what water credits the applicant must purchase from a district, if any, to serve the development.
G.
A map of the service area.
2.
The information above shall be provided in a manner that demonstrates sufficient water resources to meet commitments in terms of an overall annual water supply and daily availability.
WELL-FIELD ANALYSIS
Evaluation required with proposed land-uses that plan to use Denver Basin water in Margin B or the Central Basin, to assess whether a new proposed well field associated with the proposed land use will create water level change impacts such that the ability of neighboring wells, either on or off the subject property, to produce would be impaired. A change in water level at an adjacent well is not, in and of itself, considered to be an impairment. This analysis is typically completed using an analytical ground water model.