Stormwater Drain Illicit Discha
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MEMORANDUM
April 13, 2004
TO:
The Honorable Mayor and City Council Members
FROM:
Michael C. Van Milligen, City Manager
SUBJECT: Illicit Discharges to Stormwater Drainage System
Assistant City Engineer Gus Psihoyos recommends City Council approval of an
amendment to Chapter 44 of the City of Dubuque Code of Ordinances regarding illicit
connections and discharges to the stormwater drainage system.
The City holds an MS4 National Pollution Discharge Elimination System (NPDES)
permit. One of the minimum requirements of this permit, as published in the Federal
Register, is an ordinance or other regulatory mechanism to remove illegal discharges
into the stormwater drainage system. The revised ordinance meets the requirement by
expressly prohibiting non-stormwater related discharges into the City's system.
Some of the specific pollutants identified are: oil and other automotive fluids, yard
wastes such as lawn clippings and leaves, fertilizers, animal wastes and sediment from
soil erosion.
The City Council established an erosion policy as a priority. Moreover, NPDES Phase II
MS4 permit requirements include an erosion and sediment control ordinance (or other
regulatory mechanism). So while City staff is currently drafting an erosion and sediment
control ordinance to be presented to the City Council at a later date, this illicit discharge
ordinance justifiably includes sediment from soil erosion as a pollutant.
Lastly, the ordinance change includes the prohibition of geothermal pump-and-dump
heating and cooling systems without the expressed written consent of the City Manager.
A pump-and-dump system means a system that pumps water from the ground,
circulates it through a heating or cooling system, and then discharges it as non-
stormwater discharge into the City's stormwater drainage system.
I concur with the recommendation and respectfully request Mayor and City Council
approval.
(VlJl/~A~ f¡( ~
Michael C. Van Milligen
MCVM/jh
Attachment
cc: Barry Lindahl, Corporation Counsel
Cindy Steinhauser, Assistant City Manager
Gus Psihoyos, Assistant City Engineer
Michael A. Koch, Public Works Director
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MEMORANDUM
April 12,2004
TO:
FROM:
Michael C. Van Milligen, City Manager /ì ~
Gus Psihoyos, Assistant City Engineer ~
SUBJECT: Illicit Discharges to Stormwater Drainage System
INTRODUCTION
The purpose of this memorandum is to present a proposed amendment, illicit
connections and discharges to the stormwater drainage system, to Chapter 44 of the
City of Dubuque Code of Ordinances.
BACKGROUND
The Clean Water Act of 1972 prohibits the discharge of any pollutant into the waters of
the US from a point source, unless permitted by a National Pollution Discharge
Elimination System (NPDES) permit. Point-source pollution is categorized by the ability
to clearly identify where the pollutant enters a receiving water body (a lake, creek,
stream, river, etc.). Even after controlling point-source pollution, receiving waters
exhibited poor water quality. Therefore, in 1987 the Clean Water Act was amended to
target non-point source pollution.
In November of 1990, communities with populations of 100,000 or larger that operated
municipal separate storm sewer systems (MS4s) had to create a stormwater program
(apply for an NPDES MS4 Phase I permit) to reduce the discharge of pollutants from
their storm sewer system.
The final NPDES Phase II rule was published on December 8, 1999, requiring the City
of Dubuque to apply for an MS4 permit by March 10, 2003.
In December of 2002, the City Council approved the plan that involved the formation of
five (5) separate task forces, comprised of City staff, members of the Environmental
Stewardship Advisory Commission, and private citizens.
On March 3, 2003, the City Council approved the City of Dubuque's NPDES MS4 permit
application. The permit application was subsequently forwarded to the NPDES
permitting authority for Iowa, the Iowa Department of Natural Resources (IDNR).
DISCUSSION
One of the minimum requirements of an MS4 NPDES permit, as published in the
Federal Register, is an ordinance or other regulatory mechanism to remove illegal
discharges into the stormwater drainage system. The attached Ordinance meets the
requirement by expressly prohibiting non-stormwater related discharges into the City's
system.
Some of the specific pollutants identified are: oil and other automotive fluids, yard
wastes such lawn clippings and leaves, fertilizers, animal wastes, and sediment from
soil erosion.
The City Council established an erosion policy as a priority. Moreover, NPDES Phase II
MS4 permit requirements include an erosion and sediment control ordinance (or other
regulatory mechanism). So while City staff is currently drafting an erosion and sediment
control ordinance to be presented to the City Council at a later date, this illicit discharge
ordinance justifiably includes sediment from soil erosion as a pollutant.
Lastly, the ordinance change includes the prohibition of geothermal pump-and-dump
heating and cooling systems without the expressed written consent of the City Manager.
A pump-and-dump system means a system that pumps water from the ground,
circulates it through a heating or cooling system, and then discharges it as non-
stormwater discharge into the City's stormwater drainage system. Attached is a memo
that describes the system in detail and outlines the issues that surround the heating and
cooling system that is gaining popularity in the City. The City Manager may allow such
discharge if it does not present or will not present an imminent and substantial danger to
the operation of the MS4, public property, private property, the environment, or to the
health or welfare of persons, or Waters of the State.
RECOMMENDATION
I recommend the amending of Chapter 44 of the City of Dubuque Code by adding the
new Article VI - Illicit Connections and Discharges to the Stormwater Drainage System.
ACTION TO BE TAKEN
The City Council is requested to amend Chapter 44 of the City of Dubuque Code by
adding the new Article VI - Illicit Connections and Discharges to the Stormwater
Drainage System.
Prepared by Deron Muehring
cc: Barry Lindahl, Corporation Council
Cindy Steinhauser, Assistant City Manager
Laura Carstens, Planning Services Manager
Bob Green, Water Department Manager
Mary Rose Corrigan, Health Services Manager
Gus Psi hoyos, Assistant City Engineer
Deron Muehring, Civil Engineer II
ORDINANCE NO. 29-04
AN ORDINANCE AMENDING CHAPTER 44 OF THE CITY OF DUBUQUE
CODE OF ORDINANCES BY ADDING A NEW ARTICLE VI. ILLICIT
CONNECTIONS AND DISCHARGES TO THE STORMWATER DRAINAGE
SYSTEM
Whereas, the City Council of the City of Dubuque, Iowa desires to provide for
the health, safety, and general welfare of the citizens of the City of Dubuque
through the regulation of non-stormwater discharges to the municipal separate
storm sewer system (MS4) to the maximum extent practicable as required by
federal and state law; and
Whereas, this Ordinance establishes methods for controlling the introduction
of pollutants into the municipal separate storm sewer system (MS4) in order to
comply with requirements of the National Pollutant Discharge Elimination System
(NPDES) permit process; and
Whereas, the objectives of this Ordinance are:
(1) To regulate the contribution of pollutants to the municipal separate storm
sewer system by stormwater discharge by any user;
(2) To prohibit illicit connections and discharges to the municipal separate
storm sewer system; and
(3) To establish legal authority to carry out all inspection, surveillance and
monitoring procedures necessary to ensure compliance with this
Ordinance.
NOW, THEREFORE, BE IT ORDAINED BY THE CITY COUNCIL OF THE
CITY OF DUBUQUE, IOWA, AS FOLLOWS:
Section 1. Chapter 44 of the City of Dubuque Code of Ordinances is
hereby amended by adding thereto the following:
ARTICLE VI. ILLICIT CONNECTIONS AND DISCHARGES TO THE STORM
SEWER SYSTEM
Sec. 44-290. Definitions.
The following words, terms and phrases, when used in this Article, shall
have the meanings ascribed to them in this section, except where the context
clearly indicates a different meaning:
Best Management Practices (BMPs) means schedules of activities, prohibitions
of practices, general good housekeeping practices, pollution prevention and
educational practices, maintenance procedures, and other management
practices to prevent or reduce the discharge of pollutants directly or indirectly to
stormwater, receiving waters, or stormwater conveyance systems. BMPs also
include treatment practices, operating procedures, and practices to control site
runoff, spillage or leaks, sludge or water disposal, or drainage from raw materials
storage.
City Manager means the City Manager or the City Manager's designee.
Clean Water Act means the federal Water Pollution Control Act, 33 U.S.C. §
1251 et seq., and any amendments thereto.
Construction Activity means activities subject to NPDES Construction Permits
that result in disturbance of one (1) acre or more. Such activities include but are
not limited to clearing and grubbing, grading, excavating, filling, and demolition.
Geothermal Pump and Dump System means a system that uses a pump to
extract water from an underground aquifer, circulates the water through a heating
or cooling system, and discharges the water as non-stormwater discharge.
Hazardous Materials means any material, including any substance, waste, or
combination thereof, that because of its quantity, concentration, or physical,
chemical, or infectious characteristics may cause, or significantly contribute to, a
substantial present or potential hazard to human health, safety, property, or the
environment when improperly treated, stored, transported, disposed of, or
otherwise managed.
Illegal Discharge means any direct or indirect non-stormwater discharge to the
storm drain system, except as exempted in Sec. 44-295.
Illicit Connection means either of the following:
(a)
Any drain or conveyance, whether on the surface or subsurface, which
allows an illegal discharge to enter the storm drain system including
but not limited to any conveyances which allow any non-stormwater
discharge including sewage, process wastewater, and wash water to
enter the storm drain system and any connections to the storm drain
system from indoor drains and sinks, regardless of whether said drain
or connection had been previously allowed, permitted, or approved by
the City Manager; or,
(b)
Any drain or conveyance connected from a commercial or industrial
land use to the storm drain system which has not been documented in
plans, maps, or equivalent records and approved by the City Manager.
Industrial Activity means activities subject to NPDES Industrial Permits as
defined in 40 C.F.R., § 122.26 (b)(14).
Municipal Separate Storm Sewer System (MS4) means the streets, gutters,
conduits, natural or artificial drains, channels and watercourses, and other
facilities that are owned, operated, maintained or controlled by the City and used
for the purpose of collecting, storing, transporting, or disposing of stormwater . . .
National Pollutant Discharge Elimination System (NPDES) Stormwater Discharge
Permit means a permit issued by the Environmental Protection Agency or by a
State under authority delegated pursuant to 33 U.S.C. § 1342(b) that authorizes
the discharge of pollutants to waters of the United States, whether the permit is
applicable on an individual, group, or general area-wide basis.
Non-Stormwater Discharge means any discharge to the storm drain system that
is not composed entirely of stormwater.
Person means any individual, association, organization, partnership, firm,
corporation or other entity recognized by law and acting as either the owner or as
the owner's agent.
Pollutant means anything that causes or contributes to pollution. Pollutants may
include, but are not limited to: paints, varnishes, and solvents; oil and other
automotive fluids; non-hazardous liquid and solid wastes and yard wastes;
refuse, rubbish, garbage, litter, or other discarded or abandoned objects, articles,
and accumulations, so that same may cause or contribute to pollution; floatables;
sediment from soil erosion; pesticides, herbicides, and fertilizers; hazardous
substances and wastes; sewage, fecal coliform and pathogens; dissolved and
particulate metals; animal wastes; wastes and residues that result from
constructing a building or structure; and noxious or offensive matter of any kind.
Premises mean any building, lot, parcel of land, or portion of land whether
improved or unimproved including adjacent sidewalks and parking strips.
Soil Erosion means the detachment and movement of soil or rock fragments by
water, wind, ice or gravity.
Stormwater means any surface flow, runoff, and drainage consisting entirely of
water from any form of natural precipitation and resulting from such precipitation.
Storm water Pollution Prevention Plan means a document that describes the Best
Management Practices and activities to be implemented by a person or business
to identify sources of pollution or contamination at a site and the actions to
eliminate or reduce pollutant discharges to stormwater, stormwater conveyance
systems, andlor receiving waters to the maximum extent practicable.
Swface Waters means all waters of the state other than ground waters, which
include ponds, lakes, rivers, streams, tidal and non-tidal wetlands, public ditches,
tax ditches, and public drainage systems except those designed and used to
collect, convey, or dispose of sanitary sewage.
Wastewater means any water or other liquid, other than uncontaminated
stormwater, discharged from a facility.
Waters of the state means both surface waters and ground waters within the
boundaries of the State of Iowa and subject to its jurisdiction.
Sec. 44-291. Applicability.
This Article shall apply to all water entering the MS4 generated on any
developed and undeveloped lands unless explicitly exempted by the City
Manager.
Sec. 44-292. Responsibility for Administration.
The City Manager shall administer, implement, and enforce the provisions
of this Article.
Sec. 44-293. Severability.
The provisions of this Article are hereby declared to be severable. If any
provision, clause, sentence, or paragraph of this Article or the application thereof
to any person, establishment, or circumstances shall be held invalid, such
invalidity shall not affect the other provisions or application of this Article.
Sec. 44-294. Ultimate Responsibility.
The standards set forth herein and promulgated pursuant to this Article
are minimum standards; therefore this Article does not intend nor imply that
compliance by any person will ensure that there will be no contamination,
pollution, nor unauthorized discharge of pollutants.
Sec. 44-295. Discharge Prohibitions.
(1) Prohibition of Illegal Discharges. No person shall discharge or cause to
be discharged into the MS4 or watercourses any of the following:
(a) Materials, including but not limited to pollutants or waters containing any
pollutants that cause or contribute to a violation of applicable water quality
standards, other than stormwater.
(b) Geothermal pump and dump system discharges without the express
written consent of the City Manager. The City Manager may allow such
discharge if it does not present or will not present an imminent and
substantial danger to the operation of the MS4, public property, private
property, the environment, or to the health or welfare of persons, or
Waters of the State.
(2) The commencement, conduct or continuance of any illegal discharge
to the storm drain system is prohibited except as described as follows:
(a) The following discharges are exempt from discharge prohibitions
established by this Article: water line flushing or other potable water
sources, landscape irrigation or lawn watering, diverted stream flows,
rising ground water, ground water infiltration to storm drains, sump pump
discharge, foundation or footing drains (not including active groundwater
dewatering systems), crawl space pumps, air conditioning condensation,
springs, non-commercial washing of vehicles, natural riparian habitat or
wet-land flows, swimming pools (if dechlorinated - typically less than one
PPM chlorine), fire fighting activities, and any other water source not
containing Pollutants.
(b) Discharges specified in writing by the City Manager as being necessary to
protect public health and safety.
(c) Dye testing is an allowable discharge, but requires a verbal notification to
the City Manager prior to the time of the test.
(d) The prohibition shall not apply to any non-stormwater discharge permitted
under an NPDES permit, waiver, or waste discharge order issued to the
discharger and administered under the authority of the Environmental
Protection Agency, provided that the discharger is in full compliance with
all requirements of the permit, waiver, or order and other applicable laws
and regulations, and provided that written approval has been granted for
any discharge to the storm drain system.
(3) Prohibition of Illicit Connections. The construction, use, maintenance or
continued existence of illicit connections to the storm drain system is prohibited.
(a) This prohibition expressly includes, without limitation, illicit connections
made in the past, regardless of whether the connection was permissible
under law or practices applicable or prevailing at the time of connection.
(b) A person is considered to be in violation of this Article if the person
connects a line conveying sewage to the MS4, or allows such a
connection to continue.
Sec. 44-296. Suspension of MS4 Access.
(1) Suspension due to Illicit Discharges in Emergency Situations. The City
Manager may, without prior notice, suspend MS4 discharge access to a person
when such suspension is necessary to stop an actual or threatened discharge
which presents or may present imminent and substantial danger to the
environment, or to the health or welfare of persons, or to the MS4 or Waters of
the United States. If the violator fails to comply with a suspension order issued in
an emergency, the City Manager may take such steps as deemed necessary to
prevent or minimize damage to the MS4 or waters of the state, or to minimize
danger to persons.
(2) Suspension due to the Detection of Illicit Discharge. Any person
discharging to the MS4 in violation of this Article may have the person's MS4
access terminated if such termination would abate or reduce an illicit discharge.
The City Manager shall notify a violator of the proposed termination of its MS4
access. The violator may petition the City Manager for a reconsideration and
hearing.
(3) A person commits an offense if the person reinstates MS4 access to
premises terminated pursuant to this Section, without the prior approval of the
City Manager.
Sec. 44-297. Industrial or Construction Activity Discharges.
Any person subject to an industrial or construction activity NPDES
stormwater discharge permit shall comply with all provisions of such permit.
Proof of compliance with said permit may be required in a form acceptable to the
City Manager prior to the allowing of discharges to the MS4.
Sec. 44-298. Monitoring of Discharges.
(1) Applicability. This section applies to all facilities that have stormwater
discharges associated with industrial activity, including construction activity.
(2) Access to Facilities. The City Manager shall be permitted to enter and
inspect facilities subject to regulation under this Article as often as may be
necessary to determine compliance with this Article. If a discharger has security
measures in force that require proper identification and clearance before entry
into its premises, the discharger shall make the necessary arrangements to allow
access to representatives of the City Manager City Manager.
(a) Facility operators shall allow the City Manager ready access to all parts of
the premises for the purposes of inspection, sampling, examination and
copying of records that must be kept under the conditions of an NPDES
permit to discharge stormwater, and the performance of any additional
duties as defined by state and federal law.
(b) The City Manager shall have the right to set up on any permitted facility
such devices as are necessary in the opinion of the City Manager to
conduct monitoring and/or sampling of the facility's stormwater discharge.
(c) The City Manager shall have the right to require the discharger to install
monitoring equipment as necessary. The facility's sampling and
monitoring equipment shall be maintained at all times in a safe and proper
operating condition by the discharger at its own expense. All devices used
to measure stormwater flow and quality shall be calibrated to ensure their
accuracy.
(d) Any temporary or permanent obstruction to safe and easy access to the
facility to be inspected and/or sampled shall be promptly removed by the
operator at the written or oral request of the City Manager and shall not be
replaced. The costs of clearing such access shall be borne by the
operator.
(e) Unreasonable delays in allowing the City Manager access to a permitted
facility is a violation of a stormwater discharge permit and of this Article. A
person who is the operator of a facility with a NPDES permit to discharge
stormwater associated with industrial activity commits an offense if the
person denies the City Manager reasonable access to the permitted
facility for the purpose of conducting any activity authorized or required by
this Article.
(f) If the City Manager has been refused access to any part of the premises
from which stormwater is discharged, and he/she is able to demonstrate
probable cause to believe that there may be a violation of this Article, or
that there is a need to inspect and/or sample as part of a routine
inspection and sampling program designed to verify compliance with this
Article or any order issued hereunder, or to protect the overall public
health, safety, and welfare of the community, then the City Manager may
seek issuance of a search warrant from any court of competent
jurisdiction.
Sec. 44-299. Requirement to Prevent Control and Reduce Stormwater Pollutants
by the Use of BMPs.
The owner or operator of a commercial or industrial establishment shall
provide, at the owner or operator's own expense, reasonable protection from
accidental discharge of prohibited materials or other wastes into the municipal
storm drain system or watercourses through the use of structural and non-
structural BMPs. Further, any person responsible for a property or premise, that
is, or may be, the source of an illicit discharge, may be required to implement, at
such person's expense, additional structural and non-structural BMPs to prevent
the further discharge of pollutants to the municipal separate storm sewer system.
Compliance with all terms and conditions of a valid NPDES permit authorizing
the discharge of stormwater associated with industrial activity, to the extent
practicable, shall be deemed compliance with the provisions of this section.
These BMPs shall be part of a stormwater pollution prevention plan (SWPP) as
necessary for compliance with requirements of the NPDES permit.
Sec. 44-300. Watercourse Protection.
Every person owning property through which a watercourse passes, or
such person's lessee, shall keep and maintain that part of the watercourse within
the property free of trash, debris, excessive vegetation, and other obstacles that
would pollute, contaminate, or significantly retard the flow of water through the
watercourse. In addition, the owner or lessee shall maintain existing privately
owned structures within or adjacent to a watercourse, so that such structures will
not become a hazard to the use, function, or physical integrity of the
watercourse.
Sec. 44-301. Notification of Spills.
Notwithstanding other requirements of law, as soon as any person
responsible for a facility or operation, or responsible for emergency response for
a facility or operation has information of any known or suspected release of
materials which are resulting or may result in illegal discharges or pollutants
discharging into stormwater, the storm drain system, or water of the United
States such person shall take all necessary steps to ensure the discovery,
containment, and cleanup of such release. In the event of such a release of
hazardous materials such person shall immediately notify emergency response
agencies of the occurrence via emergency dispatch services. In the event of a
release of non-hazardous materials, such person shall notify the City Manager in
person or by phone or facsimile no later than the next business day. Notifications
in person or by phone shall be confirmed by written notice addressed and mailed
to the City Manager within three business days of the phone notice. If the
discharge of prohibited materials emanates from a commercial or industrial
establishment, the owner or operator of such establishment shall also retain an
on-site written record of the discharge and the actions taken to prevent its
recurrence. Such records shall be retained for at least three years.
Sec. 44-302. Enforcement.
(1) Notice of Violation. Whenever the City Manager finds that a person has
violated a prohibition or failed to meet a requirement of this Article, the City
Manager may order compliance by written notice of violation to the responsible
person. Such notice may require without limitation:
(a) The performance of monitoring, analyses, and reporting;
(b) The elimination of illicit connections or discharges;
(c) That violating discharges, practices, or operations shall cease and desist;
(d) The abatement or remediation of stormwater pollution or contamination
hazards and the restoration of any affected property; and
(e) Payment of administrative and remediation costs; and
(f) The implementation of source control or treatment BMPs.
(2) If abatement of a violation and/or restoration of affected property is
required, the notice shall set forth a deadline within which such remediation or
restoration must be completed. Such notice shall further advise that, should the
violator fail to remediate or restore within the established deadline, the work will
be done by a designated governmental agency or a contractor and the expense
thereof shall be charged to the violator.
Sec. 44-303. Appeal of Notice of Violation.
Any person receiving a notice of violation may appeal the determination of
the City Manager to the City Council. The notice of appeal must be received by
the City Manager within 15 days from the date of the notice of violation. Hearing
on the appeal before the City Council shall take place within 15 days from the
date of receipt of the notice of appeal. The City Council may rescind, modify or
affirm the notice of violation. The decision of the City Council shall be final.
Sec. 44-304. Enforcement Measures After Appeal.
If the violation has not been corrected pursuant to the requirements set
forth in the notice of violation, or in the event of an appeal, within 30 days of the
decision of the City Council upholding the decision of the City Manager, then
representatives of the City Manager may enter upon the subject private property
and are authorized to take any and all measures necessary to abate the violation
and/or restore the property. It shall be unlawful for any person, owner, agent or
person in possession of any premises to refuse to allow the City Manager or
designated contractor to enter upon the premises for the purposes set forth
above.
Sec. 44-305. Cost of Abatement of the Violation.
Within 30 days after abatement of the violation, the owner of the property
shall be notified by the City Manager of the cost of abatement, including
administrative costs. The property owner may file a written protest with the City
Manager objecting to the amount of the assessment within 15 days thereafter. If
the amount due is not paid within a timely manner as determined by the decision
of the City Manager or by the expiration of the time in which to file an appeal, the
charges shall certified by the City Clerk to the Dubuque County Treasurer in the
manner of a special assessment against the property and shall constitute a lien
on the property for the amount of the assessment.
Sec. 44-306. Injunctive Relief.
It shall be unlawful for any person to violate any provision or fail to comply
with any of the requirements of this Article. If a person has violated or continues
to violate the provisions of this Article, the City Manager may petition for a
preliminary or permanent injunction restraining the person from activities which
would create further violations or compelling the person to perform abatement or
remediation of the violation.
Sec. 44-307. Violations Deemed A Public Nuisance.
In addition to the enforcement processes and penalties provided, any
condition caused or permitted to exist in violation of any of the provisions of this
Article is a threat to public health, safety, and welfare, and is declared and
deemed a nuisance.
Sec. 44-309. Remedies Not Exclusive.
The remedies listed in this Article are not exclusive of any other remedies
available under any applicable federal, state or local law and it is within the
discretion of the City Manager to seek cumulative remedies.
Section 2. This Ordinance shall take effect upon publication.
Passed, approved and adopted this 19th day of April,
,2004.
Terrance M. Duggan, Mayor
Attest:
Jeanne F. Schneider, City Clerk
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MEMORANDUM
March 15,2002
TO:
Cindy Steinhauser, Assistant City Manager
FROM:
Deron Muehring, Civil Engineer
SUBJECT: Geothermal Heating & Cooling System Policy
INTRODUCTION
Numerous geothermal heating-cooling systems have been built throughout Dubuque in the past
few years. Although touted as environmentally friendly, open loop geothermal heat exchange
systems pose several problems for the City of Dubuque.
BACKGROUND
Geothermal systems are gaining popularity because they can significantly redUCE the cost of
heating or cooling a business or home. Acoording to the U.S. Environmental Protection Agency,
geothermal systems are, on average, 40 perCEnt more efficient than air-sourCE heat pumps, 48
percent better than natural gas fumaœs and 75 percent better than oi I furnaces.
Because of this reduction in energy consumption, all pollutants associated with the production
and consumption of energy are reduced, many times, the geothermal systems claim to be
environmentally friendly.
Geothermal systems are based on the fact that the earth below the frost line is a constant
temperature (around 50°F) all year long. During the winter (see figure 1), a geothermal system
absorbs heat from the ground and uses it to warm the air in a building. In the summer (see figure
2), the processed is reversed, removing heat from a building and transferring it back into the
ground.
Figure 1. Heat exchange during
the winter months.
Figure 2. Heat exchange during
the summer months.
There are two main geothermal systems in use: the closed system (depicted in figures 1 and 2)
and the open system. The main differenCE is:
The open system pumps wa1er out of an underground aquifer, circulates the water
through the system, and then either re-injects the water back into the aquifer or dumps it
onto the surfaCE into a storm sev..er, creek, pond, or river; A closed system continually
circulates an antifræzesolution.
Closed Loop Svstem
The most common type of geothermal installation is a closed loop system. The heat exchanger (a
loop of piping filled with fluid) is buried underground. The fluid circulates continuously inside
the buried pipe, absorbing heat from the earth during the winter for use inside a home or
business. In warmer months, the fluid takes heat from indoors and transfers it back into the earth.
Open Loop System
Instead of using an antifræze solution sealed inside the buried piping, an open loop system uses
water from another sourCE - like a river or well. There are two types of open systems: re-
injection and pump and dump.
The re-injection system draws water out of an underground aquifer, circulates it through the
system, and then re-injecls the water back into the aquifer. In some cases the aquifer being used
is the same aquifer that the City uses for its potable water supply. Alliant Energy asserts that,
"open loop systems are generally avoided and even prohibited in some areas because of
environmental conœms: An open loop geothermal well establishes a connection between
surfaCE water and groundwa1er. Improperly installed wells can introduCE pollutants into an
aquifer by providing a path for SUrfaCE water (run-off that carries pesticides, fertilizers, organic
materials and other contaminants) to enter underlying aquifers. According to Mike Anderson, of
the Water Supply Section of the Iowa Department of Natural Resources (lDNR), the re-injection
of geothermal water is prohibited in the State of Iowa by the "10-State Design Standards." That
is not to say that re-injection is strictly prohibited; Variances have been granted in the past.
A pump and dump system pumps water out of an underground aquifer, circulates it through
their system, and then dumps it above ground (Le. in a storm sev..er, creek, river, or pond). The
potential for depleting an aquifer of its water supply using the pump and dump system is an
environmental conœm.
DISCUSSION
Currently, the City of Dubuque is without a policy that addresses geothermal heating and cooling
systems. Because of the reasons outlined above, a policy may be warranted to protect the
interests of the City.
There is a mixture of open and closed systems in Dubuque. Wartburg Seminary College hæ a
closed loop system with 190 wells. Clark College employs a closed loop system with 48 wells.
Conversely, Loras College utilizes an open, pump and dump system; using two (2) wells they
2
pump water out of an underground aquifer, circulate it through their system, and then dump it
into a storm sev.er.
As a general rule the open - pump and dump - system requires significantly less v.ells than the
open - re-injection - system and the closed system; Therefore, open - pump and dump -
systems are significantly cheaper to construct while offering the same heating and cooling
benefits. As a result, the pump and dump system is the most economically favorable of the thræ
systems.
Unfortunately, there are other costs associated with open geothermal systems that the community
æa whole must burden.
Environmental Costs Associated with Geothermal Svstems
Dubuque's potable (water fit for human use and consumption) water supply comes from several
shallow aquifers and a few deep aquifers. The contamination of one of these aquifers would
result in a direct treatment cost to the City. As stated previously, the re-injection system presents
a situation where the contamination of groundwater is possible because the method extrads
groundwater from an aquifer, brings it above ground, circulates it through the system, then re-
injeds the water back into the aquifer. Therefore, if a pollutant contaminates the water any time
during its circulation through the system the contaminant will be spread to the underground
aquifer.
A closed loop system, although it costs more to construct, hæ a lower potential environmental
cost associated with it, æ the possibi I ity of contaminating an underground aquifer is significantly
less.
Stormwater Manaaement Costs Associated with Geothermal SyStems
A closed system does not impact the City's stormwater drainage system. An open - re-injection
- system does not impact the City's stormwater drainage system. However, the open - pump
and dump - system extensively uses the City's stormwater drainage system to dispose of water
extracted from an aquifer.
OnCE the geothermal pump and dump system is operational for the Academic Resourœ Building
currently under construction on the Loras College campus, on average over 500,000 gallons of
water wi II be dumped into a City storm sev.er per day. That's over 182,500,000 gallons of water
per year running through the City's storm sev.er system. The demand placed on the storm sewer
is only a minor conœm. The discharge from Loræ College's geothermal system is about 6% of
the storm sev.er's capacity. However, the constant flow of water through the system may
prematurely age the storm.sev.er, potentially increasing its maintenanCE needs or reducing its life
span.
3
There is another stormwater management cost associated with geothermal pump and dump
systems that discharge within the Bee Branch, loe Harbor, and Maus Lake drainage basins.
These watershed basins require the use of pumps to pass stormwater runoff to the Mississippi
River during high river s1ages. All water that runs through these drainage systems must be
physically pumped into the Mississippi River. The cost to run these pumps is bome by the City.
In addition, the increase in water flowing through these basins raise the risk of flood damage
surrounding Maus Lake, the 16th Stræt detention oell, and the loe Harbor.
Table. 1 Geothermal discharge demand placed on City pumping stations during high
M' . . . R"
ISSISSIPPI Iver staQeS.
% Geothermal % Geothermal
Existing Basin Proposed Existing Discharge to Discharge to
Pumping Basin Pumping Geothermal Ext. Basin Prop. Basin
Basin Capacity Capacity Discharge Pumping Pumping
(gpm) (gpm) (gpm) Capacity Capacity
Ice Harbor 6,200 20,000 3,550' 57.3 17.8
16th Street 200,000 NA 2,6652 1.3 NA
Detention Cell
1. Mississippi River Discovery Center, Dubuque County Courthouse, and Conference &
Education Center
2. Loras College, Alliant Energy, Dubuque Law Enforcement Center, Cottingham & Butler
(discharge unknown), Audubon School, Flynn Ready-Mix, and Elm Street Correctional
Facility (discharge unknown).
As table 1 indicates, even after tripling the pumping capacity of the loe Harbor pump station,
almost one fifth Cis) of the pumping capacity will be exploited by pump and dump geothermal
systems.
RECOMMENDATION
I recommend that the City of Dubuque establish a policy that places restrictions on the use of
geothermal pump and dump systems within the Bee Branch, loe Harbor, and Maus Lake
watershed basins. These restrictionslrequiremen1s might include the following:
1.
Require the Public Works Director's approval to use the City's stormwater drainage
facilities for the purpose of discharging geothermal wastewater (ensure that the
existing system can handle the geothermal flow);
Require the Water Department Manager's approval (ensure that the City's potable -
drinking - water source is not comprim ised);
Require that the use of all pump and dump geothermal systems be temporarily
disbanded when basin water must be pumped through the floodwall to the Mississippi
River (i.e. when the gates are closed).
Require a permit for all pump and dump systems so that the City can be assured that
all geothermal systems are in fact turned off when the floodwall gates are closed; and
Require the owners of pump and dump systems to pay a user fæ for the use of the
2.
3.
4.
5.
4
City's stormwater drainage system.
I further recommend that geothermal pump and dump systems be allowed for use in the Port of
Dubuque if the owners of the proposed systems agræ in principle to the five itmes listed above.
ACTION REQUESTED
I respectfully request that the appropriate City staff look into formulating a policy to adequately
deal with the use of pump and dump geothermal heating and oooling systems.
CC:
Barry Lindahl, Corporation Council
Michæl Koch, Public Works Director
Laura Carstens, Planning Services Manager
Gus Psihoyos, Assis1ant City Engineer
Bob Schisel, Civil Engineer
Bob Green, Water Department Manager
Mike Brekke, Water Distribution Supervisor
Brant Schuler, Water Engineering Assis1ant