EBTAG Annual Workshop and Field Trip
October 12-13, 2017

¹John Shomaker & Associates, Inc., 2611 Broadbent Parkway, NE, Albuquerque, NM, New Mexico, 87107, United States, amccoy@shomaker.com

²City of Santa Fe, 801 W. San Mateo Rd., Santa Fe, NM, 87504

³John Shomaker & Associates, Inc., 2611 Broadbent Parkway, NE, Albuquerque, NM, New Mexico, 87107, United States

In 2012 the City of Santa Fe established an ordinance regarding the Santa Fe River target flow for a Living River initiative. The Living River initiative includes the Santa Fe River from Nichols Reservoir, through the central part of town, to the west side of town where NM 599 (Santa Fe Relief Route) crosses the river channel. The Ordinance established Administrative Procedures, including requirements for monitoring of streamflow and wetted distance, and reporting. The streamflow monitoring includes streamflow measurements alone the Living River, estimated river seepage to the underlying aquifer system, tracking of diversions, and to quantify an overall water budget. Each monitoring event provided data to calculate stream flow, and average streamflow seepage along the river channel between monitoring stations, and end point of stream. The objective of the monitoring and analysis of data is to maintain compliance with acequia irrigation deliveries, compliance with Ordinance 2012-10, and to document Santa Fe River Target Flow for a ‘Living River.’

After accounting for diversions, the up-town Reach (Nichols Reservoir to St. Francis Drive) seepage rates are generally negligible. Streamflow decreased downstream of St Francis Drive due to seepage into the streambed and underlying geologic materials, and losses due to evaporation. Most seepage losses from the Santa Fe River were to groundwater in the upper coarse-grained unit of Lithosome S of the Tesuque Formation, particularly in the vicinity of the Agua Fria fault system (downstream of Ricardo Rd). A sustained release of more than 3 cfs is required to create streamflow from Nichols Reservoir to San Ysidro Crossing. When flows measured at the station below Nichols Reservoir were 5.6 cfs and higher during the Spring Pulse, flows reached the WWTF about 14 miles downstream.

Conveyance of streamflow for an ASR project could replace the Living River Initiative. An initial assessment was performed to explore the possibility of ASR along the Living River segment. The stratigraphy of the Tesuque Formation Lithosome S medium-grained unit is too complex and heterogeneous for efficient recharge and recovery. Almost all of the City Well Field is in the medium-grained unit which is not favorable for efficient recharge by infiltration of streamflow. Given the dipping beds of the Tesuque Formation, recharge will likely need to be as close as possible to the recovery well so recovery efficiency is maximized.

Initial findings include 1) the best location for ASR is downstream of Torreon Well; 2) dipping beds of Tesuque Formation will need to be defined prior to developing pilot program; 3) wells of other ownership may complicate control of area of hydraulic influence, and 4) depth to water and local perched aquifer system may limit the recharge method, storage capacity, and recovery rates.