by Larry MacDonnell

Clean Water Act
The U.S. Supreme Court heard arguments on February 21, 2006 in two related cases, among the most important to be considered under the Clean Water Act since 1985. At issue is the reach of federal authority to regulate discharges of pollutants. As readers of this column know, this question reemerged because of uncertainties raised by the Court’s 2001 SWANCC decision. These uncertainties have led to a flurry of challenges to the Corps of Engineers’ authority to regulate discharges to wetlands under Section 404.
Like other environmental statutes, the constitutional basis for the nationwide requirements of the Clean Water Act is Congress’s control of matters of interstate commerce. In matters of water, Congressional authority traditionally has been tied to navigability since rivers served as important corridors for commerce. In the context of controlling pollution, however, navigability has little meaning. Thus Congress extended the Clean Water Act to “waters of the U.S.,” a phrase likely to be given much better definition in the decisions in these cases, expected in June.
Endangered Species Act
The saga of the mouse continues. In late January, a team of researchers from the USGS released a detailed study of the genetics of the Preble’s meadow jumping mouse, finding it to be a distinct subspecies of jumping mouse. The USGS study took issue with the earlier report produced by Rob Ramey concluding the opposite. The FWS has extended its process for delisting the mouse for six months to allow time for comment.
The listing and delisting wars continued in a December 2005 federal district court opinion upholding the FWS decision not to list the Rio Grande Cutthroat Trout. Despite evidence that this species no longer exists in much of its historic range, the FWS determined that its present viability in 13 “core populations” (out of a known total of 267 populations) meant the species was not in danger of extinction. Under the ESA a species is to be listed when evidence demonstrates it is in danger of extinction “throughout all or a significant portion of its range.” Courts have disagreed about the meaning of this phrase. Here the court agreed with the FWS that the relevant “range” was defined by the 13 core populations.
The author of this column published an article in the Perspective section of The Denver Post on February 26, 2006 recommending the ESA be amended to emphasize recovery, with states and tribes offered a central role (“Saving Dwindling Species: States Should Play a Greater Role in Protection”). The Senate appears unlikely to act on the ESA this session.
With no Colorado Supreme Court water opinions reported since our last issue, we take note here of a 9th Circuit Court of Appeals decision in December involving Arizona groundwater law. A pecan farmer brought suit in federal district court against a neighboring manufacturing facility that had pumped groundwater to lower the water table enough to enable construction of an underground storage structure. Evidence indicated the pumping had dropped the groundwater level under the pecan farm from 16 to 32 feet, beyond the reach of the tree roots, and that all the trees had died. Reversing a district court decision awarding damages, the circuit court noted that Arizona groundwater law permits the extraction of underlying groundwater so long as it is for the purpose of making reasonable use of the land (not necessarily of the water) and that there is no liability for any damage occurring to an adjoining landowner.
On February 3, 2006 the seven Colorado River Basin states forwarded a letter to the Secretary of the Interior with a set of consensus proposals for river management intended to avoid litigation. The centerpiece sets out parameters for operations of Lakes Mead and Powell at different storage elevations to achieve “equalization” and modifications to operation of Lake Mead under the interim surplus guidelines. Criteria for allocating shortages among Lower Basin states and Mexico are provided. Finally, a new mechanism, “intentionally created surplus,” is offered under which a Lower Basin state could increase its usable share of water from the Colorado River by taking certain actions. The complexity of the Law of the River grows along with uses of this severely overallocated source of water.

Colorado Riparian Association