Water Resources - IMPACT - September 2017 - 23

a single household. Previously, water was
sourced from a natural spring (see Figure
2) on the property, which produces water
throughout the winter and spring, but dries
up in the summer, making it necessary to
purchase and transport water from outside
sources. The new well yielded only one pint/
minute of flow, which was not enough to
sustain household water demands.
In this situation, ASR could be used to
store spring water in the well during the
winter for use in the summer when the
spring water is no longer available. However,
key uncertainties were raised regarding
the feasibility of implementing ASR at this
location, including how quickly water could
be injected and removed, how much water
could be stored, what permits and regulations
would apply, and cost. After formulating a
conceptual model of the local hydrogeology,
we conducted a series of aquifer tests to assess
the technical feasibility of the site for ASR
and evaluated the regulatory and economic
feasibility for the case study in Oregon.

Feasibility of ASR for domestic
well owners

Transmissivity and Storativity
The transmissivity (a measure of how
well an aquifer transmits water throughout
its entire thickness) of the aquifer is an
important factor in consideration of an ASR
project because it determines the rate at which
water can be injected or recovered from the
well. It is established primarily by geological
characteristics of an area. In general, aquifers
with low transmissivity are not suitable for
ASR because the turnover rate (storage and
recovery) is limited. Correspondingly, there
is an upper limit for acceptable transmissivity
because the aquifer must be capable of
holding water over time. Previous studies
(Woody 2007) have identified the ideal range
of transmissivity for implementation of ASR
to be between 5,000 and 25,000 square feet
per day, based on Brown's site rating system
for a large-scale project (Woody 2007).
However, we speculate that transmissivities
below this range could potentially be feasible
for ASR projects with smaller storage and
recovery objectives.
Storativity is a measure an aquifer's water
storage properties. When the storativity is
too low, much of the water injected into a well
can spread out laterally and be unrecoverable.
Woody (2007) identified an acceptable range
of storativity to be between 0.0001 and 0.30.

ASR metric
An ASR metric incorporates aquifer
transmissivity to estimate whether the
aquifer's capacity to store water is adequate:
ASR metric = Tmaxh
5.6Q
In this equation, T is transmissivity,
maxh is the maximum feasible head
change in the well, and Q is the well's
pumping rate. An ASR metric equal to 1
indicates that the volume of water being
injected is equal to the available space in
the aquifer, so sites with an ASR metric
greater than 1 will likely meet storativity
requirements (Woody 2007).
In cases where existing hydrogeologic
conditions are inadequate for storage and
recovery needs, well owners may turn to
artificial stimulation techniques, such
as blasting with explosives, to improve
well performance. Well design is another
consideration. If unsuitable hydrogeologic
characteristics are anticipated prior to well
construction, the well can be designed to
accommodate an ASR system through
open borehole completion or highly
perforated casings.

Regulations
In Oregon, ASR projects are typically
regulated by the Water Resources
Department and require a limited license
for feasibility assessment under OAR 690350. Under this process, acquisition of a
long-term license and periodic water quality
tests are required following the feasibility
assessment. However, because this case study
involves an exempt well, it is regulated under
the Department of Environmental Quality's
(DEQ) Underground Injection Control
(UIC) program (OAR 340-044). Under the
UIC program, the use of "dual-purpose
wells" requires an application to the DEQ
for authorization by rule (Embleton 2012).
Water injected into wells must meet drinking
water quality standards. Water rights must
also be considered. In this case study, the
spring was exempt from a water rights
permit because it did not flow off
the property where it originated (ORS
537.141). As a result, it could be used for
domestic water supply as long as it met
quality standards.

Source water quality
Spring-sourced ASR is unique in regards
to water quality because the source water

is presumably similar in composition to the
groundwater in the well, and thus less of a
concern than water from an external source.
However, once above the ground, spring water
is subject to contamination from surrounding
elements. Under the UIC rule authorization,
this water must be of drinking water quality.

Economics
Beyond regulations and geologic factors,
the bottom line for most well owners
considering ASR is whether the project is
financially feasible. This factor must be
considered on a case-by-case basis because of
the variability of objectives for well owners.
The ability of the system to provide adequate
supply to meet demand is the foremost
concern. This goes hand-in-hand with the cost
and maintenance associated with operating
the system. Trade-offs between alternatives
should be assessed. For instance, in this case
study, it was necessary to weigh the cost of
more frequent pump operation against
the cost of importing water from an
outside source.
The successful implementation of ASR
in the Oregon Coast Range could provide
well owners with a year-round supply of
water, depending upon feasibility, at a very
local scale. ■
Julianne Robinson is an undergraduate student
in ecological engineering at Oregon State
University. As part of her honors thesis, she is
conducting a feasibility study on aquifer storage
and recovery using a domestic well outside
of Toledo, Oregon. She expects to graduate
from OSU in June 2018. Contact: robinsju@
oregonstate.edu.

Co-authors:
Todd Jarvis, Oregon State University
Todd.Jarvis@oregonstate.edu
Desirée Tullos, Oregon State University
Desiree.Tullos@oregonstate.edu

References

Embleton, David, 2012. Use of Exempt Wells As
Natural Underground Storage and Recovery Systems.
Journal of Contemporary Water Research & Education,
Vol.148(1), pp.44-54. doi: 10.1111/j.1936-704X.2012.03112.x
Händel, F., Liu G., Fank J., Friedl F., Liedl R., Dietrich,
P, 2016. Assessment of small-diameter shallow wells for
managed aquifer recharge at a site in southern Styria,
Austria. Hydrogeol J (2016) 24: 2079. doi:10.1007/s10040016-1442-7
Woody, Jennifer L., 2007. A preliminary assessment of
hydrogeologic suitability for Aquifer Storage and Recovery
(ASR) in Oregon. OSU Libraries Scholars Archive.

Volume 19 * Number 5 www.awra.org * 23


http://www.awra.org

Table of Contents for the Digital Edition of Water Resources - IMPACT - September 2017

President’s Message
Growing Up…with Managed Aquifer Recharge
Aquifer Storage and Recovery as Means to
The Regulatory Environment of Managed
The ASCE-EWRI Standard Guidelines
Managed Aquifer Recharge:
Managed Aquifer Recharge: A Global Perspective
What’s Up with Water? Sisyphus, Heraclitus and WOTUS
The New Economics of Water: Reducing CO2 Emissions in the Bay Delta Could Reverse Erosion
Domestic Well Aquifer Storage and Recovery Using Seasonal Springs
Philosophy and Ethics: The Rio Grande and the Ganges Rivers: How Human ‘Success’ is Choking the Life out of Two Great River-Spirits
ASR: Aquifer Storage Rescues a Small Water Supply District
Putting Aquifers to Work: MAR Applications in Nutrient Removal
Summer Conference Recap
Harvesting Glacial Meltwater with Managed Aquifer Recharge
AWRA State Section and Student Chapter News
In Memoriam: Peter E. Black
Herbert Scholarship Award Recipients for 2017-2018 Announced
August JAWRA Highlights
2017-2018 Editorial Calendar
Water Resources - IMPACT - September 2017 - intro
Water Resources - IMPACT - September 2017 - cover1
Water Resources - IMPACT - September 2017 - cover2
Water Resources - IMPACT - September 2017 - 3
Water Resources - IMPACT - September 2017 - 4
Water Resources - IMPACT - September 2017 - President’s Message
Water Resources - IMPACT - September 2017 - Growing Up…with Managed Aquifer Recharge
Water Resources - IMPACT - September 2017 - 7
Water Resources - IMPACT - September 2017 - Aquifer Storage and Recovery as Means to
Water Resources - IMPACT - September 2017 - 9
Water Resources - IMPACT - September 2017 - 10
Water Resources - IMPACT - September 2017 - The Regulatory Environment of Managed
Water Resources - IMPACT - September 2017 - 12
Water Resources - IMPACT - September 2017 - 13
Water Resources - IMPACT - September 2017 - The ASCE-EWRI Standard Guidelines
Water Resources - IMPACT - September 2017 - 15
Water Resources - IMPACT - September 2017 - 16
Water Resources - IMPACT - September 2017 - Managed Aquifer Recharge:
Water Resources - IMPACT - September 2017 - 18
Water Resources - IMPACT - September 2017 - 19
Water Resources - IMPACT - September 2017 - Managed Aquifer Recharge: A Global Perspective
Water Resources - IMPACT - September 2017 - 21
Water Resources - IMPACT - September 2017 - 22
Water Resources - IMPACT - September 2017 - 23
Water Resources - IMPACT - September 2017 - 24
Water Resources - IMPACT - September 2017 - 25
Water Resources - IMPACT - September 2017 - 26
Water Resources - IMPACT - September 2017 - 27
Water Resources - IMPACT - September 2017 - 28
Water Resources - IMPACT - September 2017 - 29
Water Resources - IMPACT - September 2017 - What’s Up with Water? Sisyphus, Heraclitus and WOTUS
Water Resources - IMPACT - September 2017 - 31
Water Resources - IMPACT - September 2017 - The New Economics of Water: Reducing CO2 Emissions in the Bay Delta Could Reverse Erosion
Water Resources - IMPACT - September 2017 - Philosophy and Ethics: The Rio Grande and the Ganges Rivers: How Human ‘Success’ is Choking the Life out of Two Great River-Spirits
Water Resources - IMPACT - September 2017 - ASR: Aquifer Storage Rescues a Small Water Supply District
Water Resources - IMPACT - September 2017 - 35
Water Resources - IMPACT - September 2017 - Summer Conference Recap
Water Resources - IMPACT - September 2017 - 37
Water Resources - IMPACT - September 2017 - AWRA State Section and Student Chapter News
Water Resources - IMPACT - September 2017 - In Memoriam: Peter E. Black
Water Resources - IMPACT - September 2017 - Herbert Scholarship Award Recipients for 2017-2018 Announced
Water Resources - IMPACT - September 2017 - 41
Water Resources - IMPACT - September 2017 - 2017-2018 Editorial Calendar
Water Resources - IMPACT - September 2017 - cover3
Water Resources - IMPACT - September 2017 - cover4
http://www.nxtbook.com/naylor/AWRAS/AWRAS0319
http://www.nxtbook.com/naylor/AWRAS/AWRAS0219
http://www.nxtbook.com/naylor/AWRAS/AWRAS0119
http://www.nxtbook.com/naylor/AWRAS/AWRAS0618
http://www.nxtbook.com/naylor/AWRAS/AWRAS0518
http://www.nxtbook.com/naylor/AWRAS/AWRAS0418
http://www.nxtbook.com/naylor/AWRAS/AWRAS0318
http://www.nxtbook.com/naylor/AWRAS/AWRAS0218
http://www.nxtbook.com/naylor/AWRAS/AWRAS0118
http://www.nxtbook.com/naylor/AWRAS/AWRAS0617
http://www.nxtbook.com/naylor/AWRAS/AWRAS0517
http://www.nxtbook.com/naylor/AWRAS/AWRAS0417
http://www.nxtbook.com/naylor/AWRAS/AWRAS0317
http://www.nxtbook.com/naylor/AWRAS/AWRAS0217
http://www.nxtbook.com/naylor/AWRAS/AWRAS0117
http://www.nxtbook.com/naylor/AWRAS/AWRAS0616
http://www.nxtbook.com/naylor/AWRAS/AWRAS0516
http://www.nxtbook.com/naylor/AWRAS/AWARS0416
http://www.nxtbook.com/naylor/AWRAS/AWRAS0316
http://www.nxtbook.com/naylor/AWRAS/AWRAS0216
http://www.nxtbook.com/naylor/AWRAS/AWRAS0116
http://www.nxtbookMEDIA.com