45 P.3d 693 (2002)

The BOARD OF COUNTY COMMISSIONERS OF the COUNTY OF PARK and James B. Gardner and Amanda Woodbury, Plaintiffs-Appellants,
v.
PARK COUNTY SPORTSMEN'S RANCH, LLP, a limited liability partnership, Defendant-Appellee.

No. 01SA56.

Supreme Court of Colorado, En Banc.

April 8, 2002.

*695 Bernard, Lyons, Gaddis & Kahn, P.C., Jeffrey J. Kahn, Steven P. Jeffers, Longmont, Colorado, Attorneys for Plaintiff-Appellant Board of County Commissioners of the County of Park.

Felt, Monson & Culichia, LLC, James W. Culichia, James G. Felt, Colorado Springs, Colorado, Attorneys for Plaintiffs-Appellants James B. Gardner and Amanda Woodbury.

Jean E. Dubofsky, P.C., Jean E. Dubofsky, Boulder, Colorado, Attorney for Plaintiffs-Appellants Board of County Commissioners of the County of Park and James B. Gardner and Amanda Woodbury.

Bennington, Johnson & Reeve, P.C., Kenneth J. Burke, Denver, Colorado, Attorneys for Defendant-Appellee Park County Sportsmen's Ranch, LLP.

Timothy R. Buchanan, P.C., Timothy R. Buchanan, Arvada, Colorado, Attorney for Amicus Curiae Fort Morgan Reservoir and Irrigation Company and the North Sterling Irrigation District.

*696 Hill & Robbins, P.C., David W. Robbins, Dennis M. Montgomery, Denver, Colorado, Attorneys for Amicus Curiae Rio Grande Water Conservation District.

Carlson, Hammond & Paddock, LLC, William A. Paddock, Denver, Colorado, Attorneys for Amicus Curiae Rio Grande Water Conservation District.

Carlson, Hammond & Paddock, LLC, Mary Mead Hammond, Denver, Colorado, Attorneys for the Irrigationists Association.

Trout, Witwer & Freeman, P.C., Robert V. Trout, Adam T. Reeves, Denver, Colorado, Attorneys for Amicus Curiae Northern Colorado Water Conservancy District.

Grimshaw & Harring, P.C., Wayne B. Schroeder, Jody Harper Alderman, Julie K. Blakely, Denver, Colorado, Attorneys for Amicus Curiae Douglas County Water Resource Authority.

Justice HOBBS delivered the Opinion of the Court.

In this appeal from a judgment of the District Court for Water Division No. 1 (Water Court), Plaintiffs-Appellants, the Park County Board of County Commissioners, James B. Gardner, and Amanda Woodbury (Landowners) claimed in a declaratory judgment action that the applicant for a conditional water right, Park County Sportsmen's Ranch, LLP (PCSR) has "no right to occupy the space beneath the lands of the Plaintiffs to store water or other substances on or below the surface of the lands. Any such placement or storage of water on or below the surface constitutes a trespass for which the Defendant may be liable for damages." For this proposition, the Landowners rely upon the common-law property doctrine "Cujus est solum ejus est usque ad coelum et ad inferos"^[1] (cujus doctrine). The Landowners also contend that Article XVI, sections 14 and 15, section 37-87-101(1), and other statutes require PCSR to obtain consent or condemn property interests and pay just compensation to them in connection with its conjunctive use project^[2] even though PCSR does not propose to drill into or locate any of its project's facilities on or within the Landowners' properties.

The Water Court determined that: (1) artificial recharge activities involving the movement of underground water into, from, or through aquifers underlying surface lands of the Landowners would not constitute a trespass; and (2) PCSR's proposed project would not require the Landowners' consent or condemnation and the payment of just compensation under the provisions of Article XVI, sections 14 and 15, section 37-87-101(1), or the other statutes the Landowners invoke, because the project did not involve the construction of any facilities on or in the Landowners' properties. We agree with the Water Court and uphold its judgment.

I.

The Landowners and PCSR own property in South Park, Colorado, a high mountain valley approximately seventy-five miles southwest of Denver. PCSR filed with the Water Court an application for a conditional water rights decree and plan for augmentation and exchange involving extraction from and recharge of water into the South Park formation for augmentation, storage, and beneficial use. The South Park formation is a natural geological structure containing aquifers PCSR intends to utilize in connection with its project.

PCSR owns 2,307 acres of land in South Park. As part of its conditional water rights application and plan for augmentation and exchange, PCSR claimed the right to occupy saturated and unsaturated portions of the South Park formation for water extraction, augmentation, and storage as part of a water project it calls the South Park Conjunctive Use Project intended for City of Aurora municipal use. Project features would include *697 twenty-six wells to withdraw water from the South Park formation and six surface reservoirs for artificially recharging the aquifers. PCSR's application did not propose to locate any of the project's recharge and extraction features on the Landowners' properties.

We have previously determined that the aquifers of the South Platte formation are tributary to the natural stream and projects affecting them are subject to Colorado's prior appropriation law. See Park County Sportsmen's Ranch v. Bargas, 986 P.2d 262, 275 (Colo.1999). PCSR's Water Court application sought a decree for aquifer water extraction, recharge, augmentation, exchange, and storage activities, identifying two "Reservoir Zones" within the South Platte formation in connection with its claimed "conditional underground storage rights," each zone having a volume of 70,000 acre-feet of water for a total of 140,000 acre-feet extending under approximately 115 square miles of land.

The Landowners objected to PCSR's Water Court application. They also filed a complaint for declaratory relief in the Park County District Court seeking a determination that the placement or storage of water above or below the surface of their lands, absent their consent, would constitute a trespass.

On June 14, 1999, PCSR filed a motion to transfer venue of the declaratory judgment action to the Water Court, which the Park County District Court granted.^[3] After the change of venue, PCSR answered that its project did not require the Landowners' consent. The Landowners filed a motion for summary judgment in the declaratory judgment action, which the Water Court denied on August 25, 2000.

The Water Court found that PCSR's project did not include the construction of any facilities on or in the Landowners' properties and the Landowners had not alleged that the use, benefit, and enjoyment of their properties would be invaded or compromised in any way. The Water Court determined as a matter of law that PCSR's project did not require the Landowners' consent or condemnation and payment of just compensation. The Water Court ruled that: (1) the property rights of the Landowners do not include ownership of waters tributary to a natural stream; (2) natural streams crossing the property of another may be utilized, without consent, for the transportation of water by a lawful appropriator; (3) natural stream water includes the water in the aquifers; (4) water is treated differently from a property owner's traditional rights in the land estate; (5) Colorado's eminent domain law applies only if the holder of the water use right constructs facilities on or in a non-consenting landowner's property; (6) Colorado law encourages rather than restrains the efficient utilization of the state's scarce water resources; (7) the General Assembly intended to authorize artificial recharge of natural subsurface formations and conjunctive use of ground water placed therein, as part of its maximum utilization goal for beneficial use of water; and (8) the movement of underground water into, from, or through land underlying another's property, resulting from artificial recharge into an aquifer by the holder of a decreed water right, does not constitute a trespass. At the Landowners' request, the Water Court entered judgment in favor of PCSR so that the Landowners could appeal the court's declaratory judgment ruling to us.

In PCSR's water decree application proceeding, the Water Court denied PCSR's application for a conditional decree on June 1, 2001. The Water Court determined among its findings and conclusions that: (1) PCSR's ground water model was not sufficiently reliable to permit a reasonably accurate determination of the timing, amount, and location of stream depletions or to determine the rate of aquifer recharge resulting from PCSR's recharge facilities; (2) PCSR's surface flow model was insufficiently reliable to determine stream flow or legal availability of water for PCSR's project and the model's results overestimated streams flows available to PCSR; and (3) PCSR had failed to meet its burden to quantify injurious depletions in time, place, and location in connection with *698 its augmentation plan. The Water Court characterized PCSR's project application as "a scheme to augment out-of-priority depletions with additional out-of-priority pumping" that would "exacerbate depletions to the aquifer and the river system."

PCSR is presently in the process of appealing to this Court the Water Court's dismissal of its decree application.^[4] As a result of the dismissal and appeal, the Landowners suggest that the Water Court's judgment in the declaratory judgment case before us may be moot or not ripe for decision. We do not agree; however, our decision herein does not address the merits of PCSR's application or the Water Court's rulings in that case. Rather, we address the threshold issues litigated by the Landowners and PCSR in the declaratory judgment action: whether artificial recharge and storage of water that enters portions of the aquifer beneath the surface of a person's property would constitute a trespass and whether PCSR must obtain an easement or condemn and pay just compensation to landowners in connection with its proposed conjunctive use project.

II.

The Water Court determined that: (1) artificial recharge activities involving the movement of underground water into, from, or through aquifers underlying the surface lands of the Landowners would not constitute a trespass; and (2) PCSR's proposed project would not require the Landowners' consent or condemnation and the payment of just compensation under the provisions of Article XVI, sections 14 and 15, section 37-87-101(1), or the other statutes the Landowners invoke, because the project did not involve the construction of any facilities on or in the Landowners' properties. We agree with the Water Court and uphold its judgment.

We turn first to the mootness issue and then proceed to the hydrologic and legal principles that lead us to uphold the Water Court's judgment.

A.

MOOTNESS

The Landowners argue that the Water Court's dismissal of PCSR's application for a conditional decree for lack of water availability renders moot the property issue it raised in this appeal. In the context of an application for a conditional decree, we have previously held that a finding of lack of water availability rendered determination of the property issue moot. See Bd. of County Comm'rs v. Crystal Creek Homeowners' Ass'n, 14 P.3d 325, 329 (Colo.2000). In contrast to Crystal Creek, the property issue in the declaratory judgment action — as framed by the Landowners — is a threshold issue to the Water Court's consideration of the conditional decree application. We determine that the Landowners' claim is not moot.

When parties seek declaratory relief there must be an actual controversy. Const. Assocs. v. N.H. Ins. Co., 930 P.2d 556, 561 (Colo.1996) (citing Community Tele-Comms. Inc. v. Heather Corp., 677 P.2d 330, 334 (Colo.1984)). Jurisdiction exists only if the case contains a currently justiciable issue or an existing legal controversy, rather than the mere possibility of a future claim. Heron v. City & County of Denver, 159 Colo. 314, 316, 411 P.2d 314, 315 (1966).

Here, due to the procedural posture of this case, we examine mootness in the context of declaratory judgments. The Uniform Declaratory Judgments Law (UDJL) is designed to "settle and afford relief from uncertainty and insecurity with respect to rights, status, and other legal relations; and it is to be liberally construed and administered." § 13-51-102, 5 C.R.S. (2001) (emphasis added). The UDJL also establishes who may obtain a declaratory judgment, and under what circumstances:

Any person interested under a deed, will, written contract, or other writings constituting a contract or whose rights, status, or other legal relations are affected by a statute, municipal ordinance, contract, or franchise may have determined any question *699 of construction or validity arising under the instrument, statute, ordinance, contract, or franchise and obtain a declaration of rights, status, or other legal relations thereunder.

§ 13-52-106, 5 C.R.S. (2001) (emphasis added); see also C.R.C.P. 57(a), (b). A court may refuse to render or enter a declaratory judgment or decree where such judgment or decree, if rendered or entered, would not terminate the uncertainty or controversy giving rise to the proceeding. § 13-51-110, 5 C.R.S. (2001); C.R.C.P. 57(f).

The Landowners brought this declaratory judgment action inserting the resolution of the property issue as a prerequisite determination to the merits of a conditional decree application and that PCSR should not proceed with its application unless and until the court resolved the property issues they raised. We have previously examined whether an applicant must establish that it has or can obtain the right to use land as a prerequisite to obtaining a conditional decree, as part of the "can and will" test. This requirement is established in our case law. See Gibbs v. Wolf Land Co., 856 P.2d 798 (Colo.1993); FWS Land & Cattle Co. v. Colo., 795 P.2d 837 (Colo.1990); Bubb v. Christensen, 200 Colo. 21, 610 P.2d 1343 (1980).

In FWS, the water court examined whether the applicant could establish its right to use certain state lands for a reservoir enlargement project. FWS, 795 P.2d at 838. Finding that it could not, the court dismissed the application. Id. On appeal, FWS contended, among other arguments, that the water court erred by requiring a showing of land ownership as a prerequisite to obtaining a decree for a conditional water right. Id. We held that the ownership of land and the applicant's right of access to an existing surface reservoir for its enlargement are appropriate elements to be considered in the conditional decree process. We held that the water court "properly considered FWS's ability to use the state lands for increasing storage purposes." Id. at 840.

In Gibbs, we stated that, prior to issuing a conditional decree, the water court was required to consider the question of whether the applicant, Gibbs, could legally gain access to the parcels of property that were necessary for the withdrawal and transport of water. Gibbs, 856 P.2d at 801 (stating that "prior to issuing a conditional decree, the water court was required to consider the question of whether Gibbs could legally gain access to the parcels of property that are necessary to withdraw and transport the Intex well water") (emphasis added). The Water Court determined that Gibbs could obtain the requisite interest by condemnation in the future.

Addressing and resolving property issues that opponents to a water court application raise as a threshold issue is clearly established in our case law as part of the conditional decree process. The present case differs from Crystal Creek, where we determined that unappropriated water was not available to the applicant and then held moot the property ownership issue. See Crystal Creek, 14 P.3d at 329, 344. Here, the Water Court correctly issued its declaratory judgment ruling as a predicate to proceeding to the merits of PCSR's conditional decree application, because PCSR's right to obtain a water use right for underground storage was at issue.^[5]

In sum, because the declaratory judgment act is to be liberally construed; because resolution of property ownership issues affecting water use rights is established in our case law as a proper matter for water court determination; and because PCSR has stated that, whatever action we might take with respect to its pending conditional decree application appeal, it intends to rejoin the property ownership issue by re-filing its application, we find that the case before us is not moot.^[6]

*700 B.

LANDOWNERS' TRESPASS CLAIM

Reacting to PCSR's Water Court application, the Landowners broadly framed their declaratory judgment claim for relief as follows:

Pursuant to C.R.C.P. 57, this Court should declare that defendant has no right to occupy the space beneath the lands of the Plaintiffs to store water or other substances on or below the surface of the lands. Any such placement or storage of water on or below the surface constitutes a trespass for which the Defendant may be liable for damages.

As the Water Court ascertained, the Landowners thus claimed that the movement of artificially recharged water into, from, and through portions of an aquifer extending under the surface of their lands as a result of PCSR's proposed project would constitute a trespass. The Water Court held it would not.

On appeal, the Landowners take no exception to the passage of augmentation water through the aquifers underlying their lands. They also concede that PCSR's proposed project does not involve the construction of any facilities on or within their properties. However, they contend that use of the aquifers for "storage" of PCSR's artificially recharged water within their properties would constitute a trespass.^[7] This novel proposition has attracted several amicus briefs arguing that artificial recharge, augmentation, and storage of water in aquifers are authorized by Colorado law and do not require the consent of overlying landowners, unless the project facilities are located on or within the overlying landowners' properties.

To support their theory, the Landowners invoke our decisions in Walpole v. State Board of Land Commissioners, 62 Colo. 554, 163 P. 848 (1917) and Wolfley v. Lebanon Mining Co., 4 Colo. 112 (1878). The Landowners invoke Walpole and Wolfley for the assertion that their "fee ownership includes the space underneath the land" and therefore they have a right to withhold consent and require compensation for PCSR's project.^[8] In Walpole, we invalidated a State Land Board mineral reservation the Board had made in the course of selling and conveying title to a parcel of school trust land property. In holding under the law existing at that time that the Board had authority only to convey the entire fee interest, we said:

Land has an indefinite extent upward and downward from the surface of earth, and therefore includes whatever may be erected upon it, and whatever may lie in a direct line between the surface and the center of the earth.

Walpole, 62 Colo. at 557, 163 P. at 849-50. In Wolfley, we said: "At common law a grant of land carries with it all that lies beneath *701 the surface down to the center of the earth." Wolfley, 4 Colo. at 114.

The Water Court found that "Plaintiffs have not alleged that their use, benefit and enjoyment of the estate will be invaded or compromised in any way." The Landowners simply assert that common-law principles entitle them to control the storage space in aquifers underneath the surface of their lands and grant them a remedy in trespass against migration of PCSR's water laterally into their property. The Ohio Supreme Court has rejected a very similar contention in Chance v. BP Chemicals, Inc., 77 Ohio St.3d 17, 670 N.E.2d 985 (1996). In that case, a property owner claimed that the migration of injected liquid into portions of a very deep aquifer underlying its property constituted a trespass. Determining that the injectate mixed with "waters of the state" in the aquifer, the Ohio Supreme Court rejected the property owner's claim of ownership and trespass based on the cujus doctrine. It stated:

Our analysis above concerning the native brine illustrates that appellants do not enjoy absolute ownership of waters of the state below their properties, and therefore underscores that their subsurface ownership rights are limited. As the discussion in Willoughby Hills[^[9]] makes evident, ownership rights in today's world are not so clear-cut as they were before the advent of airplanes and injection wells.

Consequently, we do not accept appellants' assertion of absolute ownership of everything below the surface of their properties. Just as a property owner must accept some limitations on the ownership rights extending above the surface of the property, we find that there are also limitations on property owners' subsurface rights. We therefore extend the reasoning of Willoughby Hills, that absolute ownership of air rights is a doctrine which "has no place in the modern world," to apply as well to ownership of subsurface rights.

Chance, 670 N.E.2d at 992.

We find the Ohio Supreme Court's discussion of state waters and limitations upon absolute subsurface ownership rights to be of particular significance to the case before us, in light of Colorado's strong constitutional, statutory, and case law holding all water in Colorado to be a public resource and allowing holders of water rights decrees the right of passage for their appropriated water through and within the natural surface and subsurface water-bearing formations. The Arizona Court of Appeals has rejected a claim of property ownership rights very similar to the Landowners' claim in this case. See W. Maricopa Combine, Inc. v. Ariz. Dep't of Water Resources, 200 Ariz. 400, 26 P.3d 1171, 1176 (App.2001); see also Los Angeles v. San Fernando, 14 Cal.3d 199, 263-64, 123 Cal.Rptr. 1, 537 P.2d 1250, 1297 (1975) (recognizing ground water storage by artificial recharge and stating that the "fact that spread water is commingled with other ground water is no obstacle to the right to recapture the amount by which the available conglomerated ground supply has been augmented by the spreading.")

Thus, we turn to Colorado law, focusing first on the hydrologic principles involving tributary aquifers and the General Assembly's authorization of conjunctive use projects involving artificial recharge, augmentation, and underground storage in aquifers.

C.

TRIBUTARY AQUIFER HYDROLOGY

Legislators, administrators, and judges generally have a better understanding of surface water systems than ground water systems. See Robert Jerome Glennon & Thomas Maddock, The Concept of Capture: The Hydrology and Law of Stream/Aquifer Interactions, Forty-Third Annual Rocky Mountain Mineral Law Institute § 22.02, at 22-7 (1997). Some states that allocate their surface water by the principles of prior appropriation nevertheless allocate ground water by a rule of capture that permits overlying *702 landowners to possess the ground water appearing under their land without regard to the effect of its extraction upon other ground water and surface water users. However, such a rule of capture defies hydrologic reality^[10] and impairs the security and reliability of senior water use rights that depend on an interconnected ground and surface water system. Colorado law contains a presumption that all ground water is tributary to the surface stream unless proved or provided by statute otherwise.^[11]Safranek v. Town of Limon, 123 Colo. 330, 334, 228 P.2d 975, 977 (1951).

An aquifer is a subsurface water bearing formation. Hydrologic continuity exists if there is a hydrologic connection between a surface stream and the water table of an aquifer. Glennon & Maddock, supra, at 22-7 to 22-8. The water moves through a shared, permeable layer. Ground water, in an interconnected hydrologic system, provides a base flow^[12] for surface streams through the saturated layer of the water bearing formation. Water added to a ground water system can increase the flow of the surface stream; conversely, well pumping that results in lowering the water table can deplete the surface stream.

Aquifers consist of unsaturated and saturated zones. The unsaturated zone contains both air and water in the spaces between the grains of sand, gravel, silt, clay, and cracks within the rock. See Ground Water and Surface Water, A Single Resource, U.S. Geological Survey Circular 1139, at 6 (1999) [hereinafter USGS]. The movement of water in the unsaturated zone above the water table is controlled by gravity and capillary forces. Georg Matthess, The Properties of Groundwater 173 (1982). In the saturated zone, these voids are completely filled with water. USGS at 6. The upper surface of the saturated zone is the water table. Id. Water that infiltrates the land surface moves vertically downward through unsaturated areas to the water table to become ground water. Once the water has infiltrated the soil, its passage downward to join the ground water depends on the geologic structures and rock composition. See Elizabeth M. Shaw, Hydrology in Practice 124 (2d. ed.1989). Storativity can be calculated for confined and unconfined aquifers. Id. at 128. The ground water typically moves laterally within the ground water system. USGS at 7. Well pumping creates a cone of depression, with the point of the inverted cone occurring at the bottom of the well pipe. This causes surrounding water in the aquifer to flow into the cone from all sides. See Fellhauer v. People, 167 Colo. 320, 331, 447 P.2d 986, 992 (1968).

The interaction between streams and tributary aquifers occurs in three basic ways: streams gain water from inflow of ground water into the surface stream, streams lose water to the aquifer from outflow from the stream, or do both by gaining water from aquifers in some reaches and losing it to aquifers in other reaches. USGS at 9. Without human intervention, the surface/ground water interconnected system "exists in a state of approximate equilibrium" which implies "a long-term balance between natural recharge and discharge processes in a groundwater basin." Glennon & Maddock, supra, at 22-10.

"Recharge," whether natural or artificial, is "the accretion of water to the upper surface of the saturated zone." USGS at 6. "Discharge" is the contribution of aquifer water that migrates to the surface. Id. *703 "Storage" is the retention of ground water in the aquifer for a temporal period. The length of the retention time depends upon the specific characteristics of the aquifer:

Aquifers have two main functions in the underground phase of the water cycle. They store water for varying periods in the underground reservoir, and they act as pathways or conduits to pass water along through the reservoir. Although some are more efficient as pipelines (e.g., cavernous limestones) and some are more effective as storage reservoirs (e.g., sandstones), most aquifers perform both functions continuously.

John C. Manning, Applied Principles of Hydrology 156 (1987). Hydrologists and commentators refer to the entire zone of saturation as a "groundwater reservoir":

While the entire zone of saturation is referred to as the groundwater reservoir, it is seldom a single, homogeneous geologic formation. Usually a variety of rock types are present at any given location, and even though they may all be saturated, they often have widely varying hydrologic properties. Some would be called aquifers and others would not. The term aquifer comes from two latin words aqua, meaning water, and ferre, to bear.

To be called an aquifer, a geologic formation must be porous and permeable. It must store, transmit, and yield significant amounts of water to springs and wells.

Id. at 148 (emphasis in original).

The extent of underground storage available for artificial recharge without interfering with the aquifer's natural recharge capacity or injuring senior ground or surface water rights is a central issue in any proposal to use an aquifer for artificial recharge and storage. See Ella Foley-Gannon, Institutional Arrangements for Conjunctive Water Management in California and Analysis of Legal Reform Alternatives, 6 Hastings W.-Nw. J. Envtl. L. & Pol'y 273, 274-75 (2000).

Because the physical characteristics of groundwater basins vary greatly, the suitability of a particular basin to serve as an area for immediate storage and later extraction depends on its hydrological and geological features, as well as on the quality of the water stored within the basin.

Id. at 277. Some aquifers may be more suitable for storage of artificially recharged water than others. Id. at 278-79.

Whether a particular aquifer can accommodate a proposed conjunctive use project is a factor to consider in a Water Court decree application in Colorado and the determination will turn upon the facts of the case. The merits of PCSR's extraction, recharge, augmentation, and storage proposal are not before us. However, resolution of the Landowners' trespass claim against PCSR's proposed use of the aquifers underneath the surface of their properties is before us. The aquifers PCSR proposes to utilize extend under approximately 115 square miles of land in South Park.

Under the Landowners' property ownership theory, each landowner would have a cause of action against PCSR or any other person attempting to pursue a conditional water rights application for storage of water in the aquifer. However, we determine that the General Assembly, in authorizing the use of aquifers for storage of artificially recharged waters pursuant to decreed conjunctive use projects, has further supplanted the Landowners' common-law property ownership theory.

Conjunctive use projects are water projects that employ the natural water bearing formations — on the land's surface and in the aquifers — in the exercise of decreed water use rights according to their priority vis-à-vis all other decreed water rights. We now discuss the General Assembly's authorization for such projects.

D.

STATUTORY AUTHORIZATION FOR CONJUNCTIVE USE PROJECTS

When parties have use rights to water they have captured, possessed, and controlled, they may place that water into an aquifer by artificial recharge and enjoy the benefit of that water as part of their decreed water use rights, if the aquifer can accommodate *704 the recharged water without injury to decreed senior water rights.

This authority resides in a number of statutory sections that implement the "Colorado Doctrine," which is that all water in the state is a public resource dedicated to the beneficial use of public and private agencies, as prescribed by law. See Chatfield E. Well Co. v. Chatfield E. Prop. Owners Ass'n, 956 P.2d 1260, 1268 (Colo.1998).

Sections 37-92-305(9)(b)^[13] and (c)^[14] provide that the Water Court may issue a conditional decree for storage of water in underground aquifers if the applicant can and will lawfully capture, possess, and control water for beneficial use which it then artificially recharges into the aquifer. Section 37-87-101(1)^[15] provides that the right to store water of a natural stream is a right of appropriation in order of priority, and section 37-87-101(2)^[16] provides that underground aquifers can be used for storage of water that the applicant artificially recharges into the aquifer pursuant to a decreed right.

The storage definition of section 37-92-103(10.5), 10 C.R.S. (2001), contains a two-part definition. The statute provides:

"Storage" or "store" means the impoundment, possession, and control of water by means of a dam. Waters in underground aquifers are not in storage or stored except to the extent waters in such aquifers are placed there by other than natural means with water to which the person placing such water in the underground aquifer has a conditional or decreed right.

Id. (emphasis added). The first part defines "storage" as the impoundment, possession, and control of water by means of a dam and describes the typical reservoir, which is a constructed impoundment. The second definition contemplates the artificial recharge of water into the aquifer for "storage" and describes the circumstances under which a decree may be issued for aquifer storage. Thus, the legislature contemplated a two-step process: that a person will capture, possess, and control water and then artificially recharge it into the aquifer for storage and subsequent use, pursuant to a decreed water right.^[17]

The General Assembly's authorization for conjunctive use projects implements basic tenets of Colorado water law that the legislature has clearly enunciated: (1) a natural stream consists of all underflow and tributary waters, § 37-92-102(1), 10 C.R.S. (2001); (2) all waters of the natural stream are subject to appropriation, adjudication, and administration in the order of their decreed priority, § 37-92-102(1)(a) & (b); (3) *705 the policy of the state is to integrate the appropriation, use, and administration of underground water tributary to a stream with the use of surface water in such a way as to maximize the beneficial use of all of the waters of the state, § 37-92-102(2); and (4) the conjunctive use of ground and surface water shall be recognized to the fullest extent possible, subject to the preservation of other existing vested rights in accordance with the law. § 37-92-102(2)(b).^[18]

Other Colorado statutes foster ground water recharge and storage. See, e.g., § 35-70-103(6)(a), 10 C.R.S. (2001) (stating that one of the duties assigned to the state soil conservation board is to develop underground water storage projects). The General Assembly has attributed the statewide problem of soil loss and loss of irrigable acreage to a lack of aquifer recharge. See, e.g., § 35-70-102, 10 C.R.S. (2001) (stating that loss of irrigable and agricultural acreage in Colorado is a result of, among other problems, "increasing the rate of withdrawal from underground water reserves without adequate attention to recharging such reserves"); see also § 37-92-301(3)(d), 10 C.R.S. (2001). Another statute encourages the erection of suitable structures and the maintaining of facilities "to increase underground storage reserves." § 35-70-103(6)(g), 10 C.R.S. (2001).

Construing the General Assembly's wording and intent and effectuating evident legislative purposes, we determine that the General Assembly has authorized the issuance of decrees for artificial recharge and storage of water in an aquifer when the decree holder lawfully captures, possesses, and controls water and then places it into the aquifer for subsequent beneficial use. The applicant bears the burden of demonstrating that the aquifer is capable of being utilized for the recharge and storage of the applicant's water without impairment to the decreed water rights of senior surface or ground water users who depend upon the aquifer for supply.^[19]

We now turn to water use rights and property ownership rights under Colorado law.

E.

WATER USE RIGHTS AND LAND OWNERSHIP RIGHTS UNDER COLORADO LAW

Colorado law differs fundamentally from the English common law it replaced. The English case of Acton v. Blundell, 12 Mees. & W. 324, 152 Eng. Rep. 1223 (1843) set forth the common-law rule of surface streams and ground water, based on Roman precedent. Enjoyment of the flowing surface stream was a riparian right of property owners whose land abutted the stream:

The rule of law which governs the enjoyment of a stream flowing in its natural course over the surface of land belonging to different proprietors is well established; each proprietor of the land has a right to *706 the advantage of the stream flowing in its natural course over his land, to use the same as he pleases, for any purposes of his own, not inconsistent with a similar right in the proprietors of the land above or below; so that, neither can any proprietor above diminish the quantity or injure the quality of the water which would otherwise naturally descend, nor can any proprietor below throw back the water without the license for the grant of the proprietor above.

Acton, 12 Mees. & W. at 348-49, 152 Eng. Rep. at 1233. In contrast to the surface stream, so the court declared, ground water moves "through the hidden veins of the earth beneath its surface; no man can tell what changes these underground sources have undergone in the progress of time." Id. at 350, 152 Eng. Rep. at 1233. The court then held that ground water was not governed by the law that applies to rivers and flowing streams; rather, it was subject to the cujus doctrine. The court asserted that ground water:

falls within that principle, which gives to the owner of the soil all that lies beneath his surface; that the land immediately below is his property, whether it is solid rock, or porous ground, or venous earth, or part soil, part water; that the person who owns the surface may dig therein, and apply all that is there found to his own purposes at his free will and pleasure; and that if, in the exercise of such right, he intercepts or drains off the water collected from underground springs in his neighbour's well, this inconvenience to his neighbour falls within the description of damnum absque injuria, which cannot become the ground of an action.

Id. at 354, 152 Eng. Rep. at 1235; see also Roath v. Driscoll, 20 Conn. 533, 541 (1850).

Advancing the national agenda of settling the public domain required abandonment of the pre-existing common-law rules of property ownership in regard to water and water use rights.^[20] Reducing the public land and water to possession and ownership was a preoccupation of territorial and state law from the outset.^[21] A new law of custom and usage in regard to water use rights and land ownership rights, the "Colorado Doctrine," arose from "imperative necessity" in the western region. This new doctrine established that: (1) water is a public resource, dedicated to the beneficial use of public agencies and private persons wherever they might make beneficial use of the water under use rights established as prescribed by law; (2) the right of water use includes the right to cross the lands of others to place water into, occupy and convey water through, and withdraw water from the natural water bearing formations within the state in the exercise of a water use right; and (3) the natural water bearing formations may be used for the transport and retention of appropriated water. This new common law established a property-rights-based allocation and administration system which promotes multiple use of a finite resource for beneficial purposes. Empire Lodge Homeowners' Ass'n v. Moyer, 39 P.3d 1139, 1146-47 (Colo.2001).

When first announcing the Colorado Doctrine, we said that "rules respecting the tenure of private property must yield to the physical laws of nature, whenever such laws exert a controlling influence." Yunker v. Nichols, 1 Colo. 551, 553 (1872) (Hallett, C.J.).

When the lands of this territory were derived from the general government, they were subject to the law of nature, which holds them barren until awakened to fertility by nourishing streams of water, and the purchasers could have no benefit from the *707 grant without the right to irrigate them. It may be said, that all lands are held in subordination to the dominant right of others, who must necessarily pass over them to obtain a supply of water to irrigate their own lands, and this servitude arise