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Memo - � �
To: Mayor and Council
Planning Commission
From: Anne Hurlburt,City Administrator
Date: May 27,2010 for Discussion at June 1,2010 Meeting
Re: Open Space Conservation Subdivisions (OSCS) and Community Water Systems
Currently the Development Code encourages community sewer and water systems in OSCS,and
awards bonus density for such systems.
The Preliminary Plat for the Tii Gavo project included a community well. After further consideration,
the developer asked to eliminate the water system in favor of individual wells,which the City Council
approved as an amendment to the Preliminary Plat.
Attached is a copy of a staff report provided to the Council when that decision was made in May of
2007. It summarizes the advantage and disadvantages of a community well. You may wish to
consider this information when determining whether the revised OSCS standards should encourage or
provide a density bonus for a community well.
1
Meeting Date: 5/1/2007
Agenda Item:
Planning Commission/City Council
Agenda Report
City of Scandia
14727 209th St. North, P.O. Box 128
Scandia, MN 55073 (651) 433-2274
Action Requested: Hold a public hearing and consider the application of Big Marine
Development, LLC. to amend the Preliminary Plat for the Tii Gavo
Open Space Conservation Subdivision.
Deadline/ Timeline: Application was received on Apri] 12, 2007. 120-day review period
ends July 11, 2007. The Final Plat application is incomplete.
Background: • At the April 3, 2007 meeting, the Planning Commission and
Council found that the elimination of the community well from the
project was a material change to the Preliminary plat, requiring an
amendment (including a public hearing) before Final Plat
approval.
• The project is an open space subdivision and a planned unit
development (PUD). The yield plan showed a maximum of 28
lots without density bonuses, 19 in the first tier of the Shoreland
District and 9 lots in the underlying Agriculture District. The
project was awarded the maximum density bonus of 100%of the
number of lots outside the Shoreland (91ots) for a total of 371ots
in the project. The project was also given PUD flexibility to
permit lot sizes smaller than 1.5 acres and buildable area less than
1 acre, and for several other features of the project (such as the
community building and accessory storage buildings.)
• The ordinance requirements for open space/ conservation
subdivisions have changed since preliminary plat approval of this
project. State law does not allow the city to apply the new
ordinance to this project, as the preliminary plat approval was less
than one year ago. However, a rough analysis of the project,
prepared by TKDA during discussion of the new ordinance,
indicated that Tii Gavo may have received a density bonus of 95%
under the new ordinance; 80%without the community well (see
the table, attached.) Under the former ordinance, the density
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OS/27/10
bonus was a more subjective matter subject to negotiation, without
specific percentages for particular features. Therefore it is not
clear how much, if any, of the bonus awarded was attributable
solely to the community well. This needs to be determined by the
Planning Commission and City Council.
• The applicant has submitted a narrative explaining their arguments
in favor of individual wells vs. a community well. Staff has also
consulted with an engineer knowledgeable in the area of water
supply(Bernie Bullert, TKDA) for advice. The consensus seems
to be that the disadvantages may outweigh the advantages of a
community well.
• Advantages of a community well appear to include:
➢ The conventional wisdom seems to be that fewer holes in the
ground eyuals less risk of contamination of the groundwater
supply. This has been advocated by the DNR.
➢ In the event of contamination of the water supply, it may be
easier to provide needed treatment at a single well, rather than
individual wells.
➢ A community well may be more closely monitored than
individua] wells, so a problem with contamination might be
discovered more quickly.
➢ If it was ever necessary to provide a public water supply to the
area, the water mains would already be in place.
• Disadvantages of a community well appear to include:
➢ The cost of the water system will be greater, particular where
the lots are large and significant lengths of pipe are required to
construct the distribution system.
➢ The environmental impacts from grading, vegetation removal
and materials used for construction of the water distribution
system could be significant.
➢ A single, high-capacity well could have a larger impact on
deeper underground water levels ("cone of depression") than
many lower-capacity wells (but not as widespread as multiple
individual wells.)
➢ While the DNR advocates fewer wells, the Minnesota
Department of Health does not, indicating that if wells are
constructed to meet well codes the additional risk of
contamination is not significant. No significant risk of
contamination has been identified at this site.
➢ Chemical treatment (such as with chlorine, or iron removal)
could be required because of the size of the system, adding
significantly to the cost.
➢ While treatment at a single well might have some advantages,
some types of treatment (such as softening) would probably
still only be economically feasible at each home.
➢ Long-term management of the water system might be more
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OS/27/10
than a homeowner's association could handle, financially and
practically, especially if it was necessary to hire a licensed
firm or individual to operate the system.
➢ Even though water mains would be in place, it is likely that the
system would not be built to the same standards that would be
required for a municipal system. This would reduce some of
the potential advantage should a public water supply be
necessary in the future.
• The city's new ordinance for Open Space Conservation
Subdivisions does give a substantial bonus for community wells
(15%). This exceeds the bonus for many other features; the bonus
for community sewage disposal systems, for example, is 10%.
The city may wish to reconsider that part of the ordinance in the
future.
Recommendation: After holding the public hearing you should determine whether or not
the proposed amendment deleting the community well should be
approved, and whether or not this would require other changes to the
plat, such as a different density bonus.
A draft resolution allowing elimination of the community well has
been provided for consideration. It can be modified as necessary if
additional changes to the preliminary plat would be required.
Attachments/ • Application for Preliminary Plat Amendment
Materials provided: . Letter dated April 17, 2007 from CMWD Engineer Daniel Fabian,
EOR
• TKDA Memorandum Dated July 6, 29006 (Analysis of
Preliminary Plat)
• TKDA Memorandum Dated July 28, 2006
• Excerpt of Town Board Minutes, September 5, 2006
• Tii Gavo- Test far Draft Conservation Subdivision amendment
• Draft Resolution OS-O]-07-03
Contact(s):
Prepared by: Anne Hurlburt, Administrator
(tii gavo prelim plat amendment)
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