Builds upon the "Biological Stress Assessment" through the identification of threats and stressors to watercourses within Pima County. It provides background on technical and water policy matters, describes potential and existing impacts to watercourses within Pima County, suggests options for reducing stressors, and outlines a number of issues for discussion withing each watershed planning unit.

Chronicles how the intention to conserve a relic population of Gila topminnow under current resource conditions is generally insufficient. We have let the resource base degrade too far to expect project and site specific responses to stem losses, much less lead to recovery. The Gila topminnow was considered to be among the most common of fishes in the Santa Cruz River system in the early 1940s. Three decades later is was considered endangered; and in another three decades time, its recovery is not foreseeable, given the piecemeal approach to protection efforts.

The purpose of this project was to compile information on groundwater withdrawals and surface water diversions near perennial streams, intermittent streams, and shallow groundwater areas previously identified by PAG for the SDCP. The information could be used to prioritize future investigations of potential impacts of these withdrawals and diversions on riparian and aquatic habitats for the SDCP.

Arizona's fish story begins in 1904 with the publication of Morton Chambrlain's "Survey of Arizona Fishes", the first detailed study by an aquatic biologist of the area. He was able to count sixteen native species in Arizona. Today more than half are either extinct or listed as threatened or endangered, and most of the rest are considered to be imperiled. In Pima County, we count more extirpated native fish than remaining residents. The story, absent a fairly dramatic change in circumstances, will end with the extirpation or extinction of all native fish in the region. This report provides an opportunity to change the circumstances of aquatic and riparian systems in eastern Pima County.

This memorandum describes (1) the potential applicability to Pima County of a national initiative to institute reforms in floodplain management; and (2) an assessment of the effectiveness of Pima County's Riparian Habitat Mitigation Ordinance (attachment). An inter-departmental team was formed to formulate specific proposals for consideration as part of the Riparian Protection Element of the SDCP and the major plan amendment to the County's comprehensive plan.

Provides a snapshot of past and current conditions, and represents the very best of collaborative efforts between the expert community and County staff. This study was made possible by a gift from Dr. Wendell Minckley of a database that provided information about all known surveys of native fish within Pima County, including the species, river basin, drainage, date, number of specimens collected, collector, museum catalogue number, citations, locality, and any comments made.

Following the May 2000 pilot study, riparian areas were delineated and vegetation communities at the biome level were identified as reflected in this report. The study area for the report consisted of all land within Pima County not under federal or Native American jurisdiction that lacks GAP status as protected land.