Nisheet Dabadge (Nishu Dabadge) — Water Law Notes 5

Groundwater

Groundwater accounts for more than 90% of the non-frozen freshwater in the hydrosphere (i.e. liquid and vaporized water); it is usually readily available near places of use, is more dependable than surface water (not prone to seasonal or drought-based fluctuations), and is not prone to transmission and evaporation losses. However, it takes time to recharge, and a large portion of groundwater aquifers are being depleted by 8 major states in America. Groundwater generally becomes less pure the lower it exists in the ground, and extraction of it can lead to sub-surface structures subsiding and causing damage to land above. Drilling and pumping costs also can be prohibitive; however, 40% of water used for irrigation comes from groundwater, and over 2/3rd of groundwater goes to agricultural uses. Groundwater extraction has grown in America to up to 20 million acre feet per year, leading to the loss of many miles of rivers.

Five main groundwater doctrines exist, which courts and legislatures in each state have combined in various different ways to create a system of groundwater right governance in different states. These include the rule of capture, “reasonable use,” correlative rights, the Restatement doctrine, and prior appropriation. It is important to understand the application of these doctrines by first having a firm basis in the underlying concepts of hydrogeology: namely, the ideas that groundwater aquifers get recharged and depleted, and that surface water and groundwater systems are connected.

Hydrogeology and Informational Limits

Water seems through the myriad of openings existing in grains of sand, silt, particles of clay, and along fractures in hard rock, slowly percolating (meters per year, depending on the intensity and duration of precipitation, the land use, the vegetation cover, and the soil character and moisture content) through the sub-surface into reservoirs (saturated zones of interconnected grain openings containing water) which exist above confining beds (usually some form of shale / clay); the top boundary of a saturated zone is called its water table, and the area above it is the unsaturated zone. Unconfined aquifers are aquifers that don’t have impermeable layers of rock above them, meaning that given enough time, the water table can rise to even surface level; confined aquifers, however, are covered by impermeable layers of rock and are essentially non-renewable resources because they do not get recharged. They can be drilled through the use of Artesian wells, which take advantage of the high water pressures (the top layer of confined groundwater aquifers is called its potentiometric surface), due to the water being trapped tightly, to bring water up to the surface.

Groundwater systems connected to streams can gain stream (provide water to the stream via base flows) or lose stream (take water from the stream); these processes depend on whether the water table (surrounding the stream) is above the stream or below the stream. Groundwater systems can also be disconnected from streams yet below them, and water can slowly percolate through unsaturated zones into aquifers, slowly mounding the water table of the saturated zone through the unsaturated zone under the stream. Withdrawals from groundwater systems near streams or surface waters can lead to reductions in surface water levels / flows due to surface waters being drawn into the wells, or being pulled into the saturated aquifers as groundwater from the aquifers is pulled out. Pumping wells can lead to cones of depression forming in saturated zones, leading to groundwater being pulled from areas around the well; these cones grow over time based on length / duration of pumping, the amount and location of recharge, and the transmissivity / permeability / storage capacity of the aquifer (leading to well interference of adjoining wells that also might have their own cones of depression).

General regional declines can occur due to a mix of geologic, climatic, and groundwater withdrawal patterns; arid areas usually see sharper declines due to smaller recharges and greater withdrawals. “Overdraft” is a term used to indicate that the water level of an aquifer is declining (can be temporary or permanent); “mining” suggests that the withdrawal is unlikely to be replenished within a reasonable period of time (judgments on this “reasonable period of time” length vary). “Safe yield” is the vague concept of ensuring that withdrawals either match the rate of recharge or do not produce an undesirable result. Because undesirable results depend on various (sometimes human) factors dependent on location (saltwater buildup on the coasts, or higher pumping costs in the High Plains), a better term would be “optimal yield.” Different areas call for different standards for groundwater withdrawals (Oregon allows for a maximum water level decline in a large area of a foot a year, with no average decline over a five-year period).

Subsidence causes large amounts of infrastructure damage in states such as California, Texas, and Arizona, due to the large amounts of groundwater being pulled out from aquifers; this pulling out of water leads to gravity compacting the aquifer, further leading to declines in the elevation of land surfaces (this process can also create sinkholes in karst landscapes). Subsidence can also cause aquifers to permanently suffer reductions in their storage capacities.

Groundwater aquifers have recently been thought of as potential places to for water storage (often having higher storage capacities than surface water storage reservoirs); storage capacity depends on the permeability of aquifer rock and the elastic properties of rock and water. Recharge rates can depend on surface conditions and can occur through surface water coverage of “recharge basins” (which percolate down to unconfined aquifers) or by well injections (for confined aquifers). Recharge efforts from recharge basins can lead to contamination and often require regular maintenance.

Groundwater disputes are difficult to manage because of two main issues: first, hydrogeological conditions are generally not understood very well for specific aquifers / basins, and second, there often isn’t enough information on the historical or current usage / withdrawals from aquifers / basins. There are three main methods for understanding the features of specific aquifers: fluorescent dye injections into groundwater (the flow of which can be tracked and observed from observation wells), pumping water from a centrally located well at a constant rate to measure the level in other observation wells, and examining samples taken from individual groundwater wells and using surface and geological observations to draw inferences about the aquifer characteristics. In regards to usage tracking, many states did not implement groundwater well and withdrawal reporting until very recently (many not even prohibiting new drilling or existing drilling from continuing) (these recording and reporting requirements mainly only apply to large wells); groundwater users fear registration because this could lead to monitoring, and eventually, withdrawal regulation.

A large portion of water wells are considered exempt from registration requirements because they are “small”; “small” is a loose term, however, as some wells producing up to 10 acre feet of water a year can receive such exemptions. Many of such small wells are operated by individual households in rural areas purely for domestic uses (due to being far away from commercial water providers, who provide water to urban and suburban users). These small wells, in sum, can still lead to large impactful withdrawals of water. In Montana, the state supreme court rejected legislation that allowed for combined well appropriations leading to up to 10 acre feet of water being extracted every year. In Fox, the Washington Court of Appeals blocked the building of a single family home by a river because the creation of a well for domestic water usage was not an “adequate water supply”; if operated, the well would take water from flows in “hydraulic continuity” with the nearby river, impinging on minimum flow requirements / senior appropriations. In Bounds, the New Mexico Supreme Court found that state law required the State Engineer to issue domestic well permits without determining the availability of unappropriated water; the idea was that water rights for exempt wells as well as appropriations granted by the State Engineer were conditional, and that while the prior appropriation doctrine did apply in this state (the plaintiff simply failed to show that the defendant’s well drilling would impair his own surface water appropriations), exempt wells could still be insulated from the state permitting process.

Groundwater pumping and depletion can now be calculated by using pumping electricity costs and groundwater depth levels to calculate how much groundwater has been pumped, or via satellites measuring monthly changes in gravity fields to monitor for aquifer depletion.

Groundwater modeling has become increasingly important for analyzing the facts of groundwater conflicts and applying regulations to groundwater usage. Groundwater models, like most models, require a proper understanding of the theory behind the systems being modeled (groundwater movement theory is well understood), sufficient computation power (which exists), and enough inputs about the actual systems being analyzed (which might not always exist; soil quality, precipitation, the three-dimensional structure of groundwater reservoirs, etc.). Samplings for inputs can be inaccurate due to the inherent randomness of such samplings, measurement error, and the fact that limited sampling cannot easily measure the highly variable physical / chemical / biological properties of groundwater systems. Still, courts and regulatory bodies have been pushing for the increased use of groundwater modeling to analyze and resolve disputes; modeling systems continue to develop and advance as time goes on, in tandem with these increased pressures for use.

The Principal Doctrines of Groundwater Law

Groundwater is typically, although confusingly, categorized as either underwater streams, percolating water, or the subflow of a surface stream; several courts have attempted to either narrow or widen the differences between these categorizations, which might all point to the same groundwater. Much of this confusion stems from the idea that surface water and groundwater systems are fairly connected in various senses. Some jurisdictions unitize surface waters that are connected to groundwater systems as “tributary groundwater,” outlining that non-tributary groundwater is groundwater that would not lead to a withdrawal effect on any natural stream if water was taken from the groundwater aquifer (Colorado has further developed the ideas of tributary and non-tributary groundwater, also distinguishing “not non-tributary groundwater” and “distinguished groundwater”).

Some waters categorically excluded from groundwater laws are mining waters (which are pumped and generated from mining pits, often being pushed to the surface and fed to agriculturalists, but often leading to the drying up of surface rivers which require stream gains from such waters, also potentially leading to future lakes being formed in the pits with water quality issues as the pits are recharged with water over time), hydraulic fracturing waters (waters used to fracture shale reservoirs; waters returning from the operations onto the surface within a few weeks of the operation are called flowback waters, while the rest of the waters returning later over time are called production waters), lithium brine waters, and “hot” waters that have geothermal usages.

The Five Doctrines of Groundwater Law

· Capture / “absolute ownership” (scattered usage): anyone can withdraw as much water from the ground as desired for any purpose, without limit on quantity or place of use

· The American “reasonable use” doctrine (humid states): same as the rule of capture, but water must be put to a reasonable use on the overlying tract (uses off the overlying tract are enjoinable if such uses cause injury to overlying tract users)

· Correlative rights (scattered usage): requires equitable sharing of water by overlying tract users; off-tract users are subordinate to overlying tract users and can only get water if there exists a “surplus” (which is often if recharge exceeds withdrawals) (off-tract users then can use prior appropriation to get the water)

· Restatement (Second) of Torts Reasonable Use (some midwestern states): allows for liability for users who reduce the water table or withdraw water in excess of a reasonable share of the annual supply / total store of groundwater (factors to determine this are the same factors for reasonable use riparianism in surface water)

· Prior Appropriation (most western states): first-in-time, first-in-right, with the quantity secured by beneficial use (some modifications made to accommodate for some of the distinctive characteristics of groundwater)

All of these doctrines are based on “individualism,” meaning that they contemplate “freedom of action where the effects of individual action cannot be demonstrated with specific proof.” States use a mixture of these doctrines, combined with common law precedent, legislation, and sometimes the use of local groundwater authorities and permitting systems to manage groundwater usage.

In Sipriano, the Texas Supreme Court found that the rule of capture was the appropriate means for governing over groundwater rights for the policy reasons that groundwater movement was far too difficult to predict for governance purposes and that any recognition of correlative rights would interfere to the material detriment of the commonwealth with drainage, agriculture, mining, highway and railroad construction, sanitary regulations, building, and the general progress of improvement in works of embellishment and utility. The court further noted that the Texas Constitution had recently been updated to authorize the creation of localized groundwater districts which managed groundwater usage on top of the rule of capture, and that this development further cemented the usage of the rule of capture in the state. Critics of this case and the ideas behind the majority opinion often cite that regulation of groundwater would actually be more beneficial, necessary, and effective (similar to oil and gas exploration regulation).

Prior appropriation is primarily used to govern groundwater rights in western states. Most of the features remain the same (quantified beneficial use, specified points of diversion and places of use, non-use leading to loss of right, transferability so long as no harm is suffered by other water rights holders, and temporal priority). However, groundwater appropriations can raise interesting issues associated with seniority; senior appropriators with shallower wells should not be able to “lock up” whole aquifers if junior appropriators dig deeper wells and take more water (should junior appropriators simply pay for the senior’s cost of having to dig a deeper well to meet his own needs? Or should the junior sell water to the senior at the cost it would have required for the senior to get water from his own shallow well?). The same “lock up” issue applies to groundwater mining, where water withdrawals greatly exceed recharges and junior appropriators will most likely dry out wells completely.

One free-market approach to groundwater allocation involves the assigning of “well-defined, fully transferable property rights” to groundwater, with the aquifer rights being split up into “flow” and “stock” components (a fixed percentage of the long-run average annual recharge and a fixed absolute quantity, to be determined by the government and used only once, of the amount of water in storage in the aquifer). The issue with this approach is that it doesn’t outline how initial allocations are to be made (and substantial investments in groundwater withdrawals already exist practically everywhere; how would reductions in these withdrawals be determined, if they exceeded the “flow” and “stock” components of this free-market water allocation approach?).

Modern Groundwater Disputes: Issues, Tools and Techniques

Groundwater disputes move past issues of shortages, often including shallow well dry-ups (regardless of water supply), increased electricity costs due to pumping, environmental initiatives and interests, industrial contamination of interconnected surface water and groundwater systems, and subsidence.

General groundwater adjudications are uncommon because of the lack of statutory basis for them in most states and the scarcity of accurate (or any) historical registration or withdrawal records, which makes the gathering of basic facts necessary for such adjudications very expensive and time-consuming (correlative rights jurisdictions face such problems, which are similar to riparian rights surface water jurisdictions). Groundwater management has, in a “highly fragmentary” and “piecemeal” way been moving towards legislative reform, given the complexity of groundwater systems and resources as compared to surface water systems.

Ogallala Aquifer USGS Report (2015)

The Ogallala Aquifer, which underlies the High Plains region covering 8 states, has seen an overall decline of 15 feet since predevelopment times (1950), with overall total recoverable water in storage equaling 2.91 billion acre feet (a reduction of 273.2 million acre feet since predevelopment), and reductions in aquifer saturated thickness by several percent.