Ord 10-B Amend Ord 4 Regulation of Building ConstructionVILLAGE OF MENDOTA HEIGHTS
Dakota County., Minnesota
AMENDMENT TO BUILDING CODE ORDINANCE
AN ORDINANCE AMENDING
AN ORDINANCE TO REGULATE,
THE CONSTRUCTION OF BUILDINGS
The Village Council of Mendota Heights ordains as follows:
(1) Ordinance No. being an ordinance to regula'Ce the
construction of buildings enacted April 16, 1956 and published
May 17., 1956, is hereby amended in the following respects.
(A) Section 1.1 thereof is amended to read as
follows:
"1.1 Before proceeding with the construction,
enlargement., alteration, repair or removal of
any building or structure., or with the con-
struction or reconstruction of any sanitary
sewage disposal system, the owner �orhls-
agent shall first obtain a permit for such
purposes from the Village Clerk and shall
pay the fees as required."
(B) Section 1.5 thereof is amended to read as
follows:
"1-5 Application for permitzhall be accom-
panied by three copies of a lot plan, drawn
to a scale not smaller than 1/8 inch per foot,
showing with reference to lot lines, for the
property with respect to which a permit is
sought and for all property located within
100 feet of any portion of the property for
which the permit is sought, the location of
all existing structures, driveways, wells,
water mains and water service lines., sewer
lines., septic tanks., distribution boxes.,
seepage,tiles., dry wells, natural and arti-
ficial bodies of water and surface drainage
systems, and showing also, with respect only
to the property for which a permit is sought.,
such of the foregoing items as are proposed
for construction,, enlargement, alteration.,
etc. and, in addition thereto, the location
of contemplated future items of the foregoing
nature, not to be covered by the permit for
which application is currently being made,
The applicant shall submit data on soil con--
ditions and ground slope, and, where a sewage
disposal system is to be installed in fill
area, compaction tests shall be submitted.
Applicant shall further provide such other
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pertinent '.sketches as may reagbnably.be re
,quested by'the-.Village Clerk., Village Engineer
or Building Inspector,,"
(C) section 1.6 thereof is amended to read as follows:
P1,6 Upon request for a permit, the Village
Council shall refer all plans and specifica-
tions to the planning commission which shall
return its recommendation to the Village Coun-
cil within ten days; provided that-in any case
where.the permit is•to include the construc-
tion or reconstruction of a sewage-disposal
system upon a lot consisting-ofleas than
twenty thousand square fe,et,.-one copy of the
lot plan shall be submitted to the Village* .
Engineer for the determination of-suchtests
as may be required under Article IV hereof,
the.expense of-which test-s..shall be borne by
the applicant for permit. Upon receipt of'the
recommendation of the planning.board and; where
applicable,, the.recommendation of the Village
Engineer-, the Village Council shall ,approve -or
reject the application for permit and instruct
the Village Clerk to issue or deny a permit."
(D) Section 3.62 is amended to read as follows:
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"3.62 The type, construction and location of
sewage disposal systems shall be in accordance
with the provisions of Article IV hereof,"
(E) Section 3.63 is hereby repealed
(F) Article IV hereof is amended by changing the de-
signation thereof to read "Article V'1 and,by renumber-
ing Sections 4.1 through 4.21 as Sections 5.1 through
5.21.
- G) There is added a new Article IV reading as follows:
"ARTICLE IV
"INDIVIDUAL SANITARY SEWAGE DISPOSAL SYSTEMS
"A6 SEPTIC TANKS
"4.1 Tank must be at least 10 feet away from
any public or community water main; house ser-
vice or dwelling. Tank must be at least 15
feet inside lot line. Tank or any portion of
drain field shall be minimum 50 feet from any
well.
"4,2 Septic tank shall have a minimum capacity
of 750 gallons for a two-bedroom residence or
less with an additional 125 gallon capacity re-
quirement for each additional bedroom, future
bedroom or combination den-guest bedroom. The
liquid depth of any tank or compartment thereof
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shall not _.be, less,-thah..4 -feet and a;. liquid
depth greater than•&-1/2.feet -shall not be
considered-An ... de.termining'the.tank.capacity.
No tank or compartment thereof shall have an
inside horizontal dimension less than 36 in-
ches. The first..'compartment in a multi-com"
partment tank or the first tank in a multiple
tank system shall not.,be less than 500,gallons
or leas than one-half of the gross volume when
necessary septic tank volume exceeds 1000 gal-
lons. Septic tanks shall be of a design ap-
proved by the Minnesota State Department of
Health. See. section 4.49 for, requirements. on
garbage disposal units.,
"4.3 Tank must be made of. either. -14. gauge.
steel, poured or precast.monolithic concrete;..-
concrete is preferred. Steel tanks.must be
provided with a properly applied bituminous
protective coating on both the interior and
exterior surfaces.
"4.4 Design of tank, baffles, and..-Inspection'.
openings shall be sized as recommended.by.the,
Minnesota State Department of Health. Varia-
tions may be approved by the Village Engineer
if they are.substantially in conformation.
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"4.5 There.shall be a cleanout or inspection
opening extending from the top of the tank to
the surface of the ground, Opening shall have
a removable tight seal or plug at the ground
surface.
"B. SEEPAGE SYSTEM
`4.6 A concrete distribution box of sufficient
size (minimum 18 inches by 18 inches, inside di-
mensions) to accommodate the necessary number-of
laterals, shall be constructed at the head of each
seepage system.
"4.7 Each lateral shall be connected separately
to the distribution box and shall not be sub-
divided. Ends of laterals shall not be inter-
connected. Each the branch shall terminate
separately in a minimum 24" dia. inspection
manhole. The trench serving each the line
within three (3) feet of the inspection man-
hole shall be excavated only to the depth of
the the line., the lower half of the last the
in each line shall be filled with concrete or
some other material to serve as a dam.
114.8 All outlets and the floor of the distri-
bution box shall be at the same elevation. The
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bottom of the inlet shall be two (2) inches
above the floor. There shall be a baffle in
front of the inlet.
114.9 The sewer from the septic tank to the
distribution box and the feeders from the dis-
tribution box to the laterals in the seepage
system shall be constructed of vitrified bell-
and-spigot the with cemented joints or cast
iron pipe. The pipe shall be laid on a grade
of 6 inches per 100 feet.
"4.10 Sewer lines to the septic tank and from
the septic tank to the distribution facility
at the seepage field where located under drive,
ways or structures shall be constructed of cast
iron.
'4.11 Seepage system laterals must be at least:
"(a) 10 feet from water mains or service
pipes constructed of brass., lead, copper,
or mechanical-joint cast iron.
t'(b) 25 feet from water.mains or service
pipes constructed of cast iron with leaded
joints.
"(c) 35 feet from water mains or service
pipes constructed of material other than
described in (a) or (b) above.
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"6.12 Seepage system must be at least 25 feet
away from any .ditch, stream,' or drain.
"6.13 Laterals and inspection manholes in the
seepage system shall not be closer than ten (10)
feet to any lot line or dwelling.
"4.14 Seepage.system shall consist of a mini-
mum of 480 square feet of seepage trench. If
a residence contains more than 3 bedrooms or
if percolation tests show a seepage rate of
less than 1 inch in 15 minutes,-the minimum
area of seepage trench shall be the amount.set
forth.in the table "Minimum Area of Seepage
Trench ". The.porosity of soil shall be.deter-
mined by means of percolation tests as prescribed
below.
"6.15 Percolation tests showing the ability
of the soil to absorb septic.tank effluent shall
be made in accordance with Part C hereof and the
results submitted to the Village Clerk or Village
Engineer of Mendota Heights.
t
"6,16 All trenches in a seepage 'system shall
comply with the following standards:
"(a) Minimum total length of seepage
trench M -» 160 feet
"(b) Minimum diameter of the 4 inches
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`,'(c) Opening .between ends of the
1/4 to 1/2..inch
"(d) Minimum number of laterals per
field 2
','(e) maximum length of individual
L
lines 100 feet
'.'(f) Bottom width of trench 24
to 36 inches
"'(g) Maximum depth of cover over
the lines 36 inches
't. (h); Preferred depth of cover over
the lines M 18 to 24 inches
"(i) maximum grade of tile lines
6 in. per 100 feet;,
Minimum grade of the lines - -.1 no
per 100 feet
"(j) Preferred grade of the lines
2 in. per 100 feet
tt (k)
the
the
shall
espec
Minimum depth of trench.fill,under
- 6 inches
Minimum depth of trench fill over
- - 2 inches
Bottom areas of separate trenches
be as nearly equal as practicable.,
Tally where the fields are placed
in ground with appreciable slope.
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`(n) Spacing of trenches - center to
center. - - 10 feet
"4.17 Grade boards, securely staked in the
bottom-of the trench, shall be provided for
all drain lines.
"4.18 Where necessary to maintain proper grade
and cover.,,lines may be terraced by use of
suitable brick and concrete drop boxes, or
I ells with cemented- joints,
"4.19 Trench fill shall be crushed stone or
gravel. Stone or gravel shall be free of dust,
,sand., clay, or fine material, Trench fill shall
be well graded from 1/4 to 1-1/2 inch in size.
"4.20 Upper halves of joints are to be covered
with pieces of asphalt treated.paper.
114.21 After placing rock or gravel over tile,
cover same with untreated building paper and
backfill trench with solidly tamped earth.
"4.22 The trench fill shall completely encase
the the as previously described, except that
seepage trenches constructed within 10 feet of
large trees or dense shrubbery shall have at
least 12,inQhes of absorption material beneath
the tile.
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"4.23 Over the inspection manhole there shall be con-
structed'a reinforced concrete top.$ at least 4 inches
thick., bearing-at least 6 inches on soil outside of the
pit, with a watertight concrete manhole and cover.
Where possible, the top shall be 6 to 12 inches below
the ground surface.
114.24 The depth of normal ground water below the bot-
tom of the seepage trench shall not be less than two
(2) feet. The !normal! ground water level for the pur-
pose of the . above requirement is to be considered at
that depth below the ground surface where water is en-
countered during a normal dry period and between the
dates of June 1 and October 1 in any year.
"4.25 The lot area proposed to be occupied by a sep-
tic tank and the seepage field shall be free from
inundation due to ponding of storm water in depressions
or on flat areas or due to flooding from streams or
other drainag& channels.
'..'4.26 Rough and finished grading of such areas shall
be so executed with respect to elevation and slope that
surface drainage is off the area and away from all
nearby wells.
114.27 If fill material is to be placed over any part
of the seepage field area or within 10 feet thereof to
a depth of'18 inches or more it shall be done as fol-
lows:
'.'(a) Porous material only shall be placed over tl-e
seepage field area and for a distance of 10 feet
beyond the end of the laterals.
','(b) For a distance of 10 feet beyond the porous
fill impervious material shall be placed and com-
pacted in such a manner as to prevent leaking at
the toe of the slope.
11(c) If the seepage system is to be installed
within 6 months of completion of the filling opera-
tion, then the fill shall be placed in 6" layers
and compacted in such a manner that the tile lines
shall not settle out of the required vertical
alignment.
"4.28 Seepage and other tile trenches shall be back-
filled and the finished grading of the seepage field
area shall be done only by hand or by such other methods
as do not involve vehicles rolling over buried tile
lines.
"4.29 After backfilling of trenches the septic tank
and seepage area shall be brought to a finished grade
and effectively fenced and marked with signs to pro-
hibit passage of trucks and other vehicles. The fence
and signs shall be maintained throughout the balance
of the construction., grading and landscaping period.
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"C. PROCEDURE FOR PERCOLATION TESTS
1.14-30 six or more tests shall be made in separate test
holes spaced over the proposed seepage field site as
directed by the Village Engineer.
'.'4-31 Dig or bore a hole, with horizontal dimensions
of from 4 to 12 inches and vertical sides to the depth
of the proposed seepage trench. In order to save time,
labor and volume of water required per test, the holes
can be bored with a 4 inch auger.
','4.32' Carefully scratch the bottom and sides of the
hole with a knife blade or sharp pointed instrument,
in order to remove any smeared soil surfaces and to
provide a natural soil interface into which water may
percolate. Remove all loose material from the hole,
Add 2 inches of coarse sand or fine gravel to protect
the bottom from scouring and Sediment,
"4.33 Carefully fill the hole with clear water. By
refilling if necessary, or by supplying a surplus
reservoir of water, such as an automatic siphon, keep
water in the hole for at least four hours, and preferably
overnight Allow the soil to swell overnight. The
saturation procedure is intended to give the soil the
opportunity to swell and approach the condition that
will prevail during normal operation of the seepage
system.
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"4.34 Percolation or seepage rate measurements shall
be made on the day following the procedure described
under the preceeding section. Add clear water to
bring the depth of water in the hole to approximately
6 inches over the gravel as necessary. From a fixed
reference point (a board laid across the top of the
hole can be used), measure the drop in water level at
approximately 30 minute intervals for at least four
hours, refilling to 6 inches over the gravel as
necessary. The drop that occurs during the final 30
minute interval, if representative of a constant rate,,
is used to calculate the percolation rate. If not
representative, consideration shall be given to the
drops which occurred during previous 30 minute inter-
vals. Unless a constant rate has been reached, the
test shall be continued. Record the results of the
tests on forms similar to.thosb supplied by the
Village Clerk of,Mendota Heights.
"4.35 compute an average of the representative
seepage rates in the six or more tests made. Con-
sult table (below) to determine necessary area of
seepage trench.
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MINIMUM AREA OF SEEPAGE TRENCH
Seepage rate: minutes for Square feet of trench for residence of
Water to -fall one inch 3 bedrooms or less 4 bedrooms 5 bedrooms
15 (or less) 48o 630 78o
16 to 20 760 950 1110
21 to 25 830 1040 1200
26 to 3o goo 1125 1305
31 to 35 970 1210 1410
36 to 40 lo4o 1300 1510
41 to 45 1110 1390 1610
46,to 50 118o 1475 1710
51 to 55 1250 1560 1810
56 to 6o 1320 1650 1915
over 60 Unsuitable for seepage system
114.36 For residences containing more than 5 bedrooms
and for all other uses, special consideration shall be
given, and the required area shall be determined by the
Village Engineer.
"D. DRY WELLS
1114-37 A !Dry Well! as des . cribed herein is also com-
monly referred to as a !Cesspool! or !Seepage Pitf.
"4.38 A dry well may be used as a substitute for a
seepage system, as previously described herein, for
effluent from a septic tank. It shall not be used as
a substitute for a septic tank.
"4.39 The dry well, as defined herein, shall be a
vertical circular opening in the ground constructed
by the use of brick, stone, concrete block or similar
materials as a lining, said.lining to be at least 3
inches thick with 2- to 4-inch open joints below the
liquid inlet. It shall have an open bottom.
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"4.40 The dry well shall have a reinforced concrete
top, at least 4-inches thick,. bearing on the wall and
extending at least 6 inches outside the well. The.top
shall.be provided with a watertight concrete manhole
cover or the top shall be constructed in sections for
easy access into the well. There shall be a cleanout
or inspection opening extending from the top of the well
to 6'," above the surface of the ground,,
','4.41 Dry wells shall be located not less than the
stated minimum distances from the following:
"(a) Any private or public well - 75 feet
'I(b) Any water supply lines - 50 feet
"(c) Dwellings -.20 feet
'.'(d) Other structures, lot lines, and driveways 10 ft.
"(e) Other existing or abandoned dry wells - 3
times the average diameter —edge to edge
"4.42 Dry well absorption area shall be calculated as
the side area, below the inlet, exclusive of any un-
suitable soil formations.
"(a) The determination of the required effective
absorption area based on the depth of dry well
required shall be made by the use of a test hole
or holes which will indicate the soil strata at
the proposed location for the well. This test
information shall be comp$led and submitted with
the plot plan to the Village Engineer for deter-
mination of the feasibility of using a dry well
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for waste disposal as well as its size and depth,
The expense of such tests shall be borne by the
applicant.
'.'(b) Required seepage area shall be determined in
accordance with the following table:
Character of Soil
Coarse sand or gravel
Fine sand
Loamy sand and silt with very little
clay (less than 50)
Sandy loam silty) -
Sandy loam �clayey)
Clay with considerable gravel or sand
Clay with small amounts of gravel or
sand
Heavy tight clay, hardpan, rock or
- other impervious formations '
Effective absorption area
requirement in square feet
of wall area of well ex-
clusive of curbing, per
bedroom
20
50
100
200
300
400
500
unsuitable
As a further clarification, the particle sizes of the various
soils are as follows:
Sand - Under 10% passing the #270 sieve.
Loamy sand - From 10 to 20%.passing the #270 sieve.
Sandy loam - Over 20% passing #270 sieve.but also the
sand content shall be over 50%
The character of soil in the above table is based on the U.S.
Bureau of Soils Classification.
"(c) A minimum of 4 feet of porous formation
for each installation shall be provided in one
or more wells. Where soil porosity is questionable,
at least 20 feet of vertical depth below inlets
shall be provided in one or more wells.
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"(d) Dry wells less than 20 feet deep shall have
a minimum diameter of 4 feet.
"(e) The bottom of any dry well shall terminate
notule5s than 10 feet above the normal ground
water table as defined in Section 4024.
"E. GENERAL PROVISIONS
"4.43 Downspouts . shall not discharge to the sewage
disposal system.
114.44 Sumps of any construction shall not be located
within 25 feet from a well. Sumps for collection of
basement wastes must be constructed of reinforced
concrete, 6 inches thick, where within 75 feet of a
well.
"4.45 separate sump pumps shall be used for collec-
tion of drainage from foundation footing drains and
from laundry, and floor wastes. Laundry and floor
wastes shall be discharged into the septic tank,
however, no footing drainage will be permitted. This
type of drainage shall be discharged onto the ground
surface outside the dwelling. Toilet wastes shall not
be discharged into a basement sump unless a sump and
sump pump designed for this purpose is provided.
"4.46 Basement drain must discharge to the sewer or
sump leading to the septic tank.
M
"4.47 Minimum size of the house sewer and house drain
shall be 6 inches if sewer is of vitrified clay, 4
inches if sewer is of cast iron. Minimum slope shall
be 1/4 inch per foot for 4 inch pipe., 1/8 inch per
foot for 6 inch pipe.
"4.48 Grease traps and catch basins, if used., unless
located inside the dwelling and above the floor, must
be located at least 50 feet away from any well or 10
feet from any water pipe and must be constructed as
described elsewhere in these specifications. Outflow
from grease traps or catch basin must discharge into
the sewer leading to the septic tank.
"4.49 Where household garbage grinders are installed
or contemplated in conjunction with individualsewage
disposal systems, the minimum liquid capacity of the
septic tank., the minimum length of tile drain field
and minimum requirements for dry wells, as specified
in the preceding parts of this Article IV shall be
increased by 50%.
"4.50 On new construction, the owner should give
consideration to the installation of a future sewer
service line under the basement floor toward the street
in front of the dwelling in the event of the installa-
tion of a municipal sewer collection system. Any such
line shall be temporarily plugged at both ends to pre-
vent the entrance of fureign matter prior to its being
placed in use.
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1114.51 All plumbing installed hereafter in buildings
subject to the jurisdiction of these regulations shall
be designed and installed in accordance with the re-
quirements set forth in the Minnesota Plumbing Code.as
amended.
"4-52 If changes from the approved design, layout,
specifications for grading submitted for a building
permit are necessitated by unforeseen conditions or
for other reasons, the changes in design, layout and
grading shall be submitted to and approved by the
Village Engineer.
"4.53 The installer of each individual sewage disposal
system shall certify, according to an approved form,
that it has been made in accordance with the approved
plot plan, other drawings and specifications as re-
quired herein.
"4-54 A permanent print of the plot plan and drawings,
or a photostat thereof made to an approved scale,
showing the actual installation shall be permanently
mounted under glass in the utility room or basement
of the house.
'4.55 An instruction card shall be permanently mounted
under glass in the utility room or basement of the
house which sets forth the following: limitations in
the use of a plumbing system that is connected to an
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individual septic tank sewage disposal system; limita-
tions in the use of the lot area over the tile seepage
field; instructions on inspection, cleaning and main-
taining the septic tank; possible reasons for improper
functioning of the system should it occur and possible
remedies,, including relocation of the seepage the
lines. All such instruction cards shall be approved
by the Village Clerk.or Village Engineer.
(H) Section 5.1 thereof (designated as Section 4.1 prior
to the amendment made by paragraph (F) hereof) is amended
to read as follows:
!'5-1 No dwelling shall be constructed upon a lot or
building plot that does not have an area of 10,000
or more square feet where public sewage disposal
exists, or an area of 15,000 or more square feet on
lots having a private or individual sewage disposal
system.'.'
(I) Section 5.18 thereof (designated as Section 4.18 prior
to the amendment made by paragraph (F) hereof) is amended
to read as follows:
"4.18 The requirements stated in this code repre-
sent minimum standards. The Village Council will
recognize and permit all construction that exceeds
these minimums. Where the Council finds that extreme
hardship will result from strict enforcement of all
provisions of this ordinance., it may waive compliance
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with specified sections, upon such conditions as it
may impose provided that it is not contrary to the
public health or public welfare to do so.','
(2) This ordinance shall take effect and be in force from and
after its passage and publicationrd
Enacted and ordained into an ordinance this day of Q
1956.
I
(Seal)
Att�Gt:
Clerk
THE VILLAGE OF MENDOTA HEIGHTS
Mayor
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