SPDSS_Task43-2_Phase2_DenverBasinRegionAquiferProperty

• Title: SPDSS Task 43.2 - Denver Basin Region Aquifer Property - Phase 2
• Description: This Technical Memorandum was undertaken under Task 43.2, and summarizes the compilation, analysis and mapping of existing published aquifer property data for the Denver Basin Region.
• Decision Support - Doc Type: Task Memorandum
• Date: 2/13/2006
• DSS Category: Groundwater
• DSS: South Platte
• Basin: South Platte
• Contract/PO #: C153953
• Grant Type: Non-Reimbursable
• Bill Number: SB01-157, HB02-1152, SB03-110, HB04-1221, SB05-084, HB06-1313, SB07-122
• Prepared By: CDM

SPDSS Phase 2 Task 43.2 Denver Basin Region
Aquifer Property Technical Memorandum
FINAL
To: Ray Alvarado, CWCB
From: Camp Dresser and McKee, Inc.
Andy Horn, Gordon McCurry, Donavon Paschall, and Matt Bliss
Subject: SPDSS Groundwater Component Phase 2, Draft Final Task 43.2 Denver
Basin Region Aquifer Property Technical Memorandum
Date: February 13, 2006
Introduction
The groundwater component of Phase 2 of the South Platte Decision Support System
(SPDSS) focuses on compiling and evaluating available relevant data to support the
Decision Support System (DSS) for the South Platte River watershed and to add the data
to HydroBase, the State of Colorado's hydrological database. The SPDSS study area is
presented in Figure 1. For the purposes of the SPDSS, the groundwater study area is
divided into two hydrologic regions. The Denver Basin Region includes the bedrock
aquifers of the Denver Basin. The South Platte Alluvium Region consists of the
unconsolidated deposits of the South Platte River mainstem, extending downstream
from just below Chatfield Reservoir to the Nebraska State line at Julesburg. The South
Platte Alluvium Region also includes the alluvium overlying the Denver Basin bedrock
aquifers in Water Divisions 1 and 2.
The current definition of the Denver Basin aquifers was established in 1985 with
promulgation of the Denver Basin Rules, 2 CCR 402-6 (DWR 1985). The four principal
bedrock aquifers of the Denver Basin are, from top to bottom, the Dawson, Denver,
Arapahoe, and Laramie-Fox Hills Aquifers. The Dawson and Arapahoe Aquifers have
been subdivided by the Colorado Division of Water Resources (DWR) into Upper and
Lower units based on the presence of lower permeability claystone and shale layers in
their respective northern extents (Figure 2).
This task was undertaken for the Colorado Water Conservation Board (CWCB) and
Division of Water Resources (DWR), under Task 43.2 of Phase 2 of the SPDSS by Camp
Dresser & McKee (CDM). Task 43.2 of the SPDSS includes the collection, analysis, and
mapping of existing published aquifer property data. The objectives of this task are as
follows:
1. Compile aquifer property information and create a HydroBase compatible
database with data from the Denver Basin Region.
2. Help identify additional data needs in this region.