United States
Environmental Protection
September 1993
                    Reuse of Municipal
                    Wastewater by Volunteer
                    Freshwater Wetlands

                    Vermontville, Michigan



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       Vermontville is a rural community
       located 25 miles southwest of
       Lansing. The local maple
 syrup industry is active; each year a
 festival brings thousands of visitors to
 this community of 825 residents.
 Vermontville considers itself "the
 sweetest little town in Michigan." There
 is no evidence of the high growth and
 bustle of more urban areas; in fact the
 local Amish folk tie up their horses
 and buggies on Main Street. Mayor
 Beverly Sue Billanueva runs the town
 and its only restaurant.
   The Clean Water Act of the early
 1970's dictated that Vermontville up-
 grade its wastewater treatment capabili-
 ties. In common with many other small
 communities, Verniontville could not
 afford to own or operate a "high tech"
 physical-chemical wastewater treatment
 plant. But it was situated to utilize the
 land-intensive natural systems tech-
 nology, and decided to do so. In 1972,
 they opted for facultative lagoons
 followed by seepage beds. Those seep-
 age beds unexpectedly became wetlands,
 a system which works remarkably well
 and is liked by the operators.
Cover: Wetland number one
is bordered by lagoons and
Anderson Highway, and is in
close proximity to an operat-
ing farm. Cattails dominate
the vegetation, with a few
willow shrubs in evidence.
Late summer senescence is in
progress, the cattails are
beginning to turn brown.
System Description

   The municipal wastewater treatment
system at Vermontville, Michigan
consists of two facultative stabilization
ponds of 10.9 acres (4.4 ha), followed
by four diked surface (flood) irrigation
fields of 11.5 acres (4.6 ha) constructed
on silty-clayey soils. The system is
located on a hill with the ponds upper-
most and the fields at descending
elevations (Figure 1). After 1991, the
nineteenth year of operation, the fields
are totally overgrown with volunteer
emergent aquatic vegetation, mainly
cattail. The system was designed for
0.1 MGD and a life of twenty years.
It is presently operated at about three-
quarters of design capacity.
   The Vermontville system was
intended, in the conceptual stages, to
provide phosphorus removal both by
harvesting of terrestrial grasses and by
soil-water contact as wastewater seeps
Figure 1. Layout of the
Vermontville wastewater treat-
ment system. Inflow may be
directed to either of the two
lagoons.  The lagoons are
discharged into wetlands 1-3.
Wetland 4 no longer receives a
direct discharge; but seepage
water from the uphill units
re-emerges into wetland 4.

downward from the irrigation fields.
Up to four inches of water applied over
several hours time once each week
would flood the fields briefly until the
water seeped away. The upper pond
(Lagoon 1, Figure 1), has separate
discharge lines into fields 1 and 2, and
the lower pond.(Lagoon 2) has separate
discharge lines into fields 3 and 4.
Fields 1-4 have all been colonized by
volunteer wetland vegetation, and are
now eutrophic emergent marshes.
   Pond-stabilized wastewater is released
into each wetland by gravity flow
through 10-in. (0.25 m) main and
8-in (0.2m) manifold pipe having
several ground level outlets in each
wetland. The lagoons and wetlands are
terraced on a steep  hillside (Figure 2),
providing ample driving force for
gravity flow. Should the water level
exceed 6 in. (15.2 cm), water would
overflow to the next wetland by means
of standpipe drain. All applied water
would seep into the ground before
leaving the treatment area.
  The system is operating nearly in
this manner today. There is a constant
surface overflow from the final wetland,
made up of ground-recycled wastewater
which enters the final field at springs.
The direct surface overflow from
wetland 3 has been taken out of service.
Essentially, the system is a seepage
wetland complex and very similar to a
conventional flood irrigation facility.
The vegetation and relatively small
surface overflow from the final wetland
provides an established system in which
to evaluate the treatment aspects of
seepage combined with lateral flow-
through wetlands, the potential nutrient
removal and wildlife values of these
strictly voluntary wastewater wetland,
and the economics of the system.
   A thorough study of water quality and
other aspects of  system was conducted
in 1978, by Dr. Jeffrey Sutherland of
Williams and Works and Professor
Frederick Bevis  of Grand Valley
University. This  work was sponsored
by The National Science Foundation.
                                              Lagoon 1
Figure 2. Cross section of
the Vermontville wastewater
treatment system. The units are
set on a steep hillside, with
large driving forces for the
gravity flow from lagoons to
wetlands. Elevations shown on
the left are in feet above sea
level. Overflow occurs out of
wetland 4 to the right.

      . tiring 1990, approximately 29
      |MG of wastewater was intro-
       duced into the lagoons. This was
 a dry year. Evaporation exceeded rain-
 fall and snowmelt, leaving only about
 22 MG to discharge to wetlands 1,2,
 and 3. There was no lagoon discharge
 to wetland 4. About 7 MG were lost
 to evaporation in the wetland cells,
 13 MG infiltrated to groundwater, and
 2 MG overflowed from wetland 4 to
 the receiving stream.
  Wetland 4 receives its water from
 interior springs fed by the groundwater
 mound under the upgradient wetlands,
 most importantly wetland 3. The direct
 discharge to wetland 4 was
 discontinued, since it was in
 close proximity to the system
 outflow point, and was
 clearly short-circuiting water
 across wetland 4. Effluent
 discharged from the system
has therefore passed through
 the lagoons, then through the
 upper wetlands, the soils
under the site, and finally
through the last wetland.
I      he facility operates under an
      NPDES Permit issued by
      Michigan DNR. The outflow
from wetland 4 is to an unnamed
tributary of the Thornapple River,
which is protected for agricultural uses,
navigation, industrial water supply,
public water supply at the point of
water intake, warm water fish and total
body contact recreation. There are
presently no industrial dischargers. The
discharge limitations from the treatment
wetlands (Table 1) are set for a design
flow of 0.1 MGD. Discharge is limited
to the ice free high flow periods from
May 1-October 31.
Table 1 . Discharge limitations for the
Vermontville wastewater treatment facility. •

c /-\ n /o r\
o/ 1 -y/ou
All Year
All Year
Daily Daily 30-Day 7-Day
Minimum Maximum Average Average
25mg/l 17mg/l
14lb/d 21 Ib/d
	 	 10 mg/l 5mg/l
4.2 Ib/d 8.3 Ib/d !
16mg/l 11 mg/l
9,2 Ib/d 13.3 Ib/d
20 mg/l 30 mg/l
30 mg/l 45 mg/l
7 mg/l
2.2 mg/l
5 mg/l
1.0 mg/l
0.83 Ib/d
5 mg/l
6 mg/l
5 mg/l
6.5 9.0

Compliance Monitoring

   The overflow from final wetland field
4 contains a fairly constant volume of
effluent which has seeped from the
higher elevation wetlands, flowed
through the ground, and entered field
4 springs. This treated effluent is of high
quality, as is the ground water recovered
from the project's monitoring wells.
   The outflow is monitored weekly.
Total suspended solids (TSS) was well
within permit limits at all times during
1990 (Figure 3), indicating that the
wetlands had effectively filtered and
settled particulate material.
   Carbonaceous biological oxygen
demand (CBOD) also remained within
30-day average permit limits in 1990,
and there was only one excedance of
the seven-day permit limit of 5 mg/1.
The CBOD load in the surface
 discharge was less than 10% of that
 allowed by the permit.
   Total phosphorus in the surface
 discharge was also well within permit
 limits, with an average 1990 value of
 0.24 mg/1 compared to the permit level
 of 1.0 mg/1 (Figure 4). The same was
 true for ammonium nitrogen, which
 averaged 0.86 mg/1 compared to the 2.2
 mg/1 permit requirement. Both phospho-
 rus and nitrogen display considerable
 variability, which is characteristic of
 many wetland systems. The seasonal
 trends in ammonium nitrogen^—an
 increase followed by a decrease—have
 been observed at other sites, and are
 therefore probably real. They are likely
 due to the changing processes  of plant
 uptake and decomposition.
                                                                             Figure 3. Both CBOD and
                                                                             TSS fluctuate in the outflow
                                                                             from the wetlands, but the
                                                                             seasonal averages are quite low;
                                                                             3.5 mg/lfor CBOD; 4.2 mg/l
                                                                             for TSS. (Data are for 1990)
              CBOD, mg/1
              TSS, mg/1
   120      150
     180      210      240      270       300
June      July     August   September   October
                                   Figure 4. The nutrients
                                   phosphorus and ammonium
                                   nitrogen were well within limits
                                   in the wetland outflow in 1990.
                                   The seasonal average total
                                   phosphorus was 0.24 mg/l;
                                   ammonium nitrogen averaged
                                   0.86 mg/l.
   120      150      180      210       240      270      300
        May      June      July     August  September   October

   Dissolved oxygen averaged 7.0 mg/1
 in 1990, with a range from 5.4 to 9.4,
 which included a four excedances of
 minor nature. pH ranged from 6.6 to
 7.2, well within the permit range.
   Fecal coHform counts (Figure 5)
 are within limits for surface water
 discharges, but are higher than at other
 comparable wetland sites.

 Research Results

   Some of the more detailed water
 quality results for 1978 are summarized
 in Figure 6. Greater than two-fold dilu-
 tion across the system was evident in
 the decreasing chloride concentration
 from 280 mg/1 in the effluent to 124 mg/1
 in the ground water. Pond effluent was
 25% diluted with respect to influent.
 Although a few inches of precipitation
 in excess of evaporation from the ponds
 occurred during the summer, the 25%
 dilution was more importantly due to
 excessive snow and ice meltwater added
 to the ponds in spring 1978. The 25%
 dilution between the  pond effluent and
 the water standing in the wetlands was
 due principally to a large number of
 sampling dates coinciding with signifi-
 cant rainfall. Greater than 20 inches
 (50.8 cm) of rain fell in the 4 ]/i months
 from June to mid October, which was
 approximately 50% higher than the
 normal rate. The decrease in concentra-
 tion between irrigation fields and
 ground water was due to .mixing of
wastewater with more dilute ambient
ground water.
   Phosphorus was removed to the
extent of around 97% between the

  « 100=

  I    E
  'o    —
          i   i  I  i   I  I  i   i  i  i  i   i  i  i   i  i  i  i   i  i  i   i  i
       120      150      180      210      240      270       300
            May      June      July     August  September  October
 wetland fields and the ground water,
 which was sampled from monitoring
 wells placed at depths ranging from
 roughly 10 ft. to 25 ft. (3.0 m to 7.6 m)
 below the wetland floors. Most removal
 of phosphorus occurs in the upper
 3 ft. (0.9 m) of soils judging from a
 small number of lysimeter samples
 which averaged 0.11 mg/1 total P and
 0.06 mg/1 ortho-P, with ranges of
 0-0.3 mg/1 and 0-0.2 mg/1, respectively.
 The average removals of phosphorus
 effected in the upper 3 ft. (0.9 m) of
 soils were approximately 95%.
  Levels of nitrate-nitrogen increased
 approximately 60% between the pond
 discharge and the wetland standing
water, indicating that aerobic bacteria
were at  work in the wetland waters.
 On the other hand, the sediments were
anaerobic as evidenced in the fetid
odor which evolved when they were
disturbed. Loss of some of the nitrate
by denitrification was apparently
                                  Figure 5. Fecal coliform
                                  bacteria counts also fluctuate
                                  in the outflow from the
                                  wetlands, but the seasonal
                                  average is quite low; the
                                  geometric mean value was 77.
                                  (Data are for1990)

occurring. Lysimeter samples showed
nitrate-nitrogen ranging from 0.0 to
0.9 mg/1, which suggested that denitri-
fication of approximately 60% of the
nitrate occurred in the shallow wetland
soils. The ambient ground water
contained higher levels of nitrate-nitro-
gen than did the seeping wastewater,
perhaps indicating some further nitri-
fication during passage through the soil.
  Levels of TKN and ammonia-
nitrogen seemed not to change much
between the pond discharge and the
wetland waters. But this constancy was
likely only apparent, with organic
nitrogen and ammonia probably
being produced through anaerobic
decomposition in the wetland sediments
and being consumed in the aerobic
wetland waters.
Incoming Wastewater
Lagoon Discharge
    Lysimeter @ 3ft
Wetland Discharge
                                                                            Figure 6. Profiles of water
                                                                            quality in 1978. Lagoons
                                                                            and wetlands and soils are
                                                                            functioning to remove
                                                                            nutrients in this system.
                                                                            During the early life of the
                                                                            facility, there were lagoon
                                                                            discharges directly to wetland
                                                                            4; and there was surface
                                                                            overflow directed from
                                                                            wetland 3 to wetland 4. This
                                                                            resulted in some short-circuit-
                                                                            ing to the surface outflow,
                                                                            and consequently higher
                                                                            phosphorus numbers  than in
                                                                            the present mode of operation.

       The wetlands were observed to
       contain eight plant communities
       in 1978. These included areas
 dominated by grassland, duckweed,
 cattail and willow. In 1991, the grassland
 and duckweed communities were no
 longer significant. The wetlands are now
 dominated entirely by cattail and willow
 shrubs and trees.
   Standing crops (above ground plant
 parts) for the wetlands varied from a
 minimum of 830 to over 2,200 gm/m2 in
 the wetlands in 1978. Visual estimates in
 1991 indicate that the standing crops are
 presently somewhat higher than that
 maximum, and more uniform. There
 appears to be approximately 3,000
 gm/m2 at all locations, not counting
 trees. Because the wetlands are located
 on an exposed hillside, winds can and do
 blow down the cattails. The result is a
 patchy stand of cattail, about three
 meters in height where it is erect, and
 flat on the surface elsewhere.
   The phosphorus in the prevailing
 cattail standing crop is significant
 compared to the phosphorus released
 into the wetlands. Cattail harvesting
 would therefore be a means of reducing
 effluent phosphorus. But harvesting is
 not needed for phosphorus removal in
 seepage wetland settings where sub-
 surface soil types and volumes are
 adequate to effect phosphorus removal
 before effluent ground water reaches
receiving streams. The expense and
difficulty of harvesting further preclude
its use at Vermontville.
       Casual observation reveals the
       wastewater-grown wetlands have
       significantly added to the
 acreage of suitable, adequately isolated
 habitat for waterfowl and other wildlife
 in the Vermontville area. Natural,
 interrupted zones of attached aquatic
 plant life fringe the nearby Thornapple
 River, but these are narrow, small and
 easily accessible to fisherman and
 other recreationists. The wastewater
 wetlands are part of a restricted public
 access area.
   The Vermontville volunteer wetland
 system created marshland habitat
 suitable for waterfowl production other-
 wise not present in the immediate area.
 Many other types of birds also nest in
 the marshes, including red-wing black-
 birds, American coot, and American
 goldfinch. Waterfowl (blue-winged teal
 and mallard), shorebirds (gallinule,
 killdeer, lesser yellow-legs, and sand-
 piper) and swallows use the wetland
 pond system for feeding and/or resting
 during their migration. Great blue
 heron, green heron, ring-neck pheasant,
 and American bittern have also been
 seen frequenting the wetlands.
  These volunteer wetlands are also
 important habitat for numerous
 amphibians and reptiles. These include
 snapping and painted turtles, garter
 and milk snakes, green and leopard
frogs, bullfrogs and American toads.
Muskrats inhabit the wetlands, while
raccoon, whitetail deer, and woodchuck
are seen feeding in the wetlands.

      Very little wetland maintenance
      has been required at Vermontville.
      The berms are mowed three or
four times per year, for aesthetic reasons
only. Water samples are taken on a
weekly frequency at the surface outflow.
The discharge risers within the wetlands
are visited and cleaned periodically
during the irrigation season. There is
essentially nothing to be vandalized, and
there have been no repairs required.
  The dikes are monitored for erosion,
which has not been a significant
problem. Muskrats build lodges and
dig holes in the dikes; and woodchucks
also dig holes in the
berms. Therefore, a
trapper  is allowed on
the site to remove these
animals periodically.
The operator also
periodically tears the
muskrat lodges apart.
  There are no bare
soil (tilled) areas to
be plugged through
siltation caused by rain
splash, spray irrigation,
or flood-suspension of
inorganic soils. The
Vermontville wetlands
showed buildup of
three or four inches
(0.1 m)  or organic
residues largely in the
form of cattail straw
after six irrigation
seasons (1972-78). That
litter mat is still of the
same thickness today,
but is accompanied by a small accretion
of new organic sediments and soils.
There was one attempt to burn the
accumulated detritus, which proved to
be difficult, and of no value in the system
operation or maintenance. The amounts
of this material have not compromised
the freeboard design  of the embank-
ments over the system's 19+ year
operational period. Tree control has not
been practiced at Vermontville, and the
wetlands now contain willow trees up to
several meters in height. No hydraulic
problems have been experienced due
to these trees, or any  other cause.
Wetland number two contains
more and larger willows.
Together with the narrow
leaved cattail, these two species
dominate the wetland.

      The Vermontville ponds and
      wetlands cost $395,000 to build in
      1972. Much of this expense was
incurred for grading, because of the
uneven topography of the site.
  The operating and maintenance costs
associated with the wetlands portion of
the treatment system are quite low. In
1978, these were approximately $3,500
per year, of which $2,150 was labor and
field costs, and the balance for water
quality analytical services. In 1990, these
same costs totalled about $4,200, includ-
ing $3,400 for labor and field costs.
      The treatment system is under
      the supervision of Mr. Tony
      Wawiernia, Superintendent,
Department of Public Works,
121 South Main Street, Vermontville,
MI 49096. Phone (517) 726-1429.
  The designers and engineers for this
facility were Williams and Works, Inc.,
611 Cascade West Parkway S.E.,
Grand Rapids, MI 49506.
Phone (616) 942-9600.
  Professor Fred Bevis visits the site
with his students on a regular basis,
and collects information on vegetation
and other aspects of the ecosystem.
Fred is Chairman of the Department of
Biology, Grand Valley State University,
Allendale, MI 49401.
Phone (616) 895-3126.

The ponds at Vermontville are
set into a hillside that drops
off more than 70 feet. This
view of lagoon 2 shows the
high and wide berms that this
relief necessitates. In late
summer, these are covered with
a profusion of wildflowers.

      The 1978 research work is detailed
      in a report to The National
      Science Foundation under Grant
No. NSF ENV-20273, May 1978. This
report is available from the National
Technical Information Service. Confer-
ence reprints summarizing the work
were prepared, and may be obtained
by contacting Professor Bevis:
  Applied Ecology Group
  11628104th Ave.
  West Olive, MI 49460-9632
Sutherland, J. C. and F. B. Bevis, 1979.
Reuse of Municipal Wastewater by
Volunteer Fresh-Water Wetlands.
IN: Proceedings of Wetland Reuse
Symposium, Vol. 1, p. 762-781.
AWWA Research Foundation,
Denver, CO.

Bevis, F. B., 1979. "Ecological
Considerations in the Management of
Wastewater-Engendered Volunteer
Wetlands," presented at the Michigan
Wetlands Conference, MacMullan
Center, Higgins Lake, MI.
  A brief summary description also may
be found in:

Sutherland, J. C., 1982. "Michigan
Wetland Wastewater Tertiary Treatment
Systems," Chapter 16 in: Water Reuse,
E. J. Middlebrooks, ed., Ann Arbor
Science Publishers, Inc., Ann Arbor, MI.