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.
In the early 1990s, a study of the Tanque Verde Creek by Dr. Julie Stromberg and others described the relationship between the depth to groundwater and the health of the mesquite woodland habitat in the area. This report revisits the Stromberg study to describe variations in groundwater levels since the report was completed early last decade. They identified around 3,000 acres of riparian vegetation in the Tanque Verde-Agua Caliente shallow groundwater zone.
Concerns research into the origin of water sustaining the Bingham Cienega. For purposes of long term management, we need to understand what the source of water is for the various riparian areas.
Conducted for the Pima County Flood Control District by the Pima Association of Governments in order to determine if stormflows on the Cienega Creek have changed over time when analyzed in terms of frequency, volume, and seasonallity. In a data search that extends back to the 1950s, they were able to determine the daily mean flow, the flows over base, and the annual peak flows of the Cienega Creek.
Ten watercourses in eastern Pima County were selected because, except for one, each has a 100-year discharge in excess of 10,000 cfs, and each is located within an urbanized or urbanizing area, or in an area where an increasing number of permits are being sought to develop in the floodplain.
Elements of the comprehensive plan now include planning for water resources that must address the currently available surface water, groundwater, and effluent supplies and provide an analysis of how the future growth projected in the county plan will be adequately served by the legally and physically available water supply. This is the first study to be issued as part of the Water Resources Element and identifies a number of measures that can be taken to conserve water, including measures that can be taken by Pima County in the form of ordinance adoption.
Provides basic information about the source of surface water in Cienega Creek at the downstream end of the natural preserve, which will contribute to efforts to conceptualize and implement effective land management proposals for the SDCP. Study results indicate that the surface flow or subflow from Agua Verde Creek do not significantly influence the water in the Cienega Creek.
Saguaro National Park encompasses two geographically distinct areas: Rincon Mountain District and Tucson Mountain District. Of the two, only Rincon Park has significant riparian habitat due to Tanque Verde Ridge. The scope of this study includes Rincon Creek, its tributary riparian areas and Tanque Verde Creek riparian tributary areas within or immediately adjacent to the Park. Both of these creeks have riparian resources that will likely be impacted by proposed development adjacent to the Park boundaries.