Agenda Date: 11/15/2016
Subject:
Title
An ordinance on second reading granting a temporary easement to Civil and Environmental Engineering Department Colorado State University for a streambed study in South Platte Park
Body
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Presented By: |
Mark Relph, Public Works and Utilities Director |
POLICY QUESTION:
Does city council support granting a temporary construction easement to Colorado State University’s (CSU) Civil and Environmental Engineering Department for a streambed study in South Platte Park?
BACKGROUND:
The City of Littleton owns the SPP property, located north of C-470 and along the South Platte River. Parcels of land were acquired beginning in the 1970’s to preserve the natural floodplain. Parts of the streambed were recently stabilized through a joint effort of the City of Littleton, South Suburban Parks and Recreation (SSPR), Arapahoe County, and Urban Drainage & Flood Control District.
Centennial Water & Sanitation District (Centennial W & S) owns and operates municipal water supply wells adjacent to the east boundary of the park between West Mineral Avenue and C-470. When Centennial W & S pumps water from its wells, the impact of groundwater drawdown on adjacent park trees, or flow in the river are not well known. Centennial W & S has been working with CSU’s Civil and Environmental Engineering Department to develop the scope of a study to better determine effects of shallow groundwater pumping not only in Littleton, but throughout the lower South Platte River basin. CSU has determined the portion of South Platte Park adjacent to Centennial W & S wells is an ideal site for such a study due to available river flow gauges data, Chatfield Reservoir outlet control, and Centennial W & S pumping schedules.
Centennial W & S has asked the City of Littleton to grant a temporary construction easement to CSU, who will drill temporary monitoring wells in SPP for the study.
STAFF ANALYSIS:
CSU proposes to drill five, temporary small diameter (4”) and shallow wells ranging in depth from 3 to 20 feet. The location in SPP is on the east and west banks of the river, south of West Mineral Avenue and north of C-470 as shown on Exhibit A. The wells will be equipped with water depth monitoring devices. CSU will also use temporary devices to measure stream flow in the river and adjacent to the monitoring wells.
The duration of the study and the easement will be about six months. Upon completion of the study, the temporary wells will be removed in accordance with State requirements. Well drilling will be completed by small equipment to minimize disruption to the environment. Disturbed vegetation will be replanted.
South Suburban Park & Recreation District (SSPR) manages SPP under an intergovernmental agreement with the City of Littleton. SSPR staff reviewed the streambed study request and support it. SSPR granted a Temporary Access Permit to CSU to conduct the study.
Public use of the park should not be negatively affected by the study. The study area will remain open to public use at all times. Temporary wells will be installed, marked and locked to prevent tampering. The study will be conducted during the season of low river flows over the next six months, when public use of the river is less than during the summer.
The results of the study will be shared with the city and SSPR.
FISCAL IMPACTS:
Granting the easement by the city is proposed at no cost to CSU or Centennial W & S. The study is being funded by a $50,000 grant from the Colorado Water Conservation Board and a $50,000 contribution from Water and Environmental Systems Technology, Inc.
STAFF RECOMMENDATION:
Staff recommends the city grant the easement.
PROPOSED MOTION:
Proposed Motion
I move to approve the ordinance on second reading granting a temporary construction easement to Colorado State University’s Civil and Environmental Engineering Department for a streambed study in South Platte Park.