ML19340D468

Effects of Dewatering on in Dunes Natl Lakeshore.

ML19340D468
Person / Time
Site:	Bailly
Issue date:	11/26/1980
From:	Geis J, Olson J, Darryll Willard INDIANA UNIV., BLOOMINGTON, IN, NEW YORK, STATE UNIV. OF, COLLEGE OF ENVIRONMENTAL, OAK RIDGE NATIONAL LABORATORY
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'M d.kkd%p$5 FINAL PANEL REPORT t j d

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"Effetts of Dewatering on the Indiana Dunes National Lakeshore" en i

Submitted to i Indiana Dunes National Lakeshore US Department of the Interior l National Park Service .

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• 4 Panel Members Caniel Willard, Chair:1an Orie Loucks School of Public and -

. The Institute of Ecolooy Environmental Affairs Holcombe Research Institute i Inciana University 4600 Sunset Avenue Eicomington, IN 47405 Indianapolis, IN 46208 James W. Geis Jerry Olson S' ate University of New York Environmental Sciences Division College of Environmental Science Oak Ridoe National Laboratory

! and Forestry Oak Ridge, TN 37830 j Syracuse, NY 13210 v:c :-- -- .

November 26, 1980 .

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1. Introduction A. Objectives '

The objectives of this are to report on the available informaticn b'ase' and provide an evaluation of the prospective effects on the Cowles Bog National Landmark area, and neighboring ecosystems, of up to a 1.'5. drop in water levels upon completion of the current sealing of fly ash ponds and up to a 2.9 drop in water levels upor, abatement of seepage plus the proposed increased pumpage from the confined sand aquifer underlying both the NIPSCO and Cowles Bog areas.

In addition, the report is intended to summarize principles that could guide decisiens related to resource protection if additional

{ata were forthcoming, and to suggest guidance as to additional studies for providing such data.

B. Background

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The Cowles Bog Wetland Complex (CBq'C) includes the Cowles Bog National Natural Landmark and the surrounding Great Marsh within the Indiana Dunes National Lakeshore. It has been a subject of sj;udy, interpretation and scientific papers since the late 19tn century (Cowles 1899,1901; Lyon 1927, Xurz 1923, Olson 1951, Hendrickson and Wilcox 1979). Industrial development in the area during the past 20 years appears to have modified the hydrology and water chemistry of at least parts of the greater CBWC area (see fieyer and Tucci 1979:,

andrelatedmaps). Mineral Springs Road is one of a series of impacts 1

which include ditching, farming, fire suppression and ash pond see,' age.

Portions have been used for a golf course and a residential development (Cook and Jackson 1978).

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. 2 Increasingly nersuasive evidence has accumulated recently supporting the viewpoint that the water regime of wetlands represents thd str,gle most important group nf envirormental variables defining the extent, specie compositions, and stability of these systems (Gosselink and Turner 1978, Veller 1978, Geis 1979, Bedford and Loucks 1980), Small deviations'in water regime, on the order of inches during some seascns,

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whibar induced by natural processes or regulation, initiate disturbance and compositional change, but the course of the changes is difficult to credict (Willard 1978). These conclusions are supported by studies in shoreline wetlands along Lake Erie (Mcdonald 1955) and Lake Ontario (Gets and Kee 1977), and in shallow marshes in Wisconsin (Bedford and Lgucks1980). The chances in the wetlands are expressed as modifications in primary production and competitive dynamics, senescence and die-off of both dominants and rare snecies in the communities, and tenocrary niche filling or compositional displacement by agoressive soecies. Shifts in the vecetative surface as outlined above are tichtly 1 inked to other e osystem functions and affect wetland values (Walker and Coupland 1967).

C. Importance of the Area The Cowles Bog and surrounding marshes and dunes have long had hich priority among proposals for expanded protection within Indiana Dunes (01 son 1958, Willard 1975). Public ownership now allcws (and requires) a more critical analysis of the significance of contrasting sub-units within the National Landmark formally dedicated as "Cowles Bog"lin 1966 (Reshkin et al.1975, Hendrickson and Wilccx 1979).

The antiquity (indicated by tritium dating) of the ground water up .

@ ling in the upmounded " spring mire" core area of the Landmark noses important questions for comparison and contrast with nutrient-rich -fens

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3 and rain fed-bogs that are core studied in Et.roce than in l' orth Ar. erica.

The spring-mire and the rest of the swamp and marsh complex '(CSh'C), like the neiohboring dune savannas and prairie ccmolex, will allow further tests ,and updating of general ecological princioles introduced by Coales (1899, 19,01). Examples include the classic soil acidity studies by Kurz (1923), the bio-geo ,orphological work of Olson (1958) and reviews of early cencepts of succession which once attracted students of natural ecosystems (Shelford 1913).

The CBriNL combines a number of ecosystems and communities in a scientifically significant array. The combination of physical and biotic communities offer many opoortunities for study and public inter-pretation. The value of CBNNL is heightened because it is already in public hands. Given the imcortance of the site historically and scientifically, human interference should be kept to a minimum.

II. The Imolications of Water Regigg i Interventions A. The Links to Ground Water The several reports available to the panel show convincirjgly that l

the current prevailing water regime at CBNNL is controlled largely by a ground water system which ori:;inates off the site, and to a much lesser degree by precipitatien and surface ficws within the surface watershed. The designation spring mire" has been sugcested for the upmounded central area of the CBWC in recognition of this relaticnship (Hendrickscn and Wilcox 1979 unpublished) and we endorse that usage.

l A description of the ground water system, including its hydraulic l

i characteristics, component aquifer and non-water bearing units, and ,

lateral variations in stratigraphy is provided in Meyer and Tucci (1979) and Gillies and Lapham (1980). The linkage of the oround water syJtem

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to surface waters in CSiiiil and the Great !!arsh has been noted in these and other reports. Thelinkaceis<1emonstratedbythehydrogdologic

" unit one" peizometer level which are at or near the organic matter surfac,e in the Great Marsh. These observations, reinforced by the Meyer and Tucci study (1979) strongly suagest that changes in the

. ground water system will have en immediate and significant effect on the surface water at the CSWC, and particularly in the CBNNL.

Generally we accept the hypotheses that the spring mire is dependent on " unit three" water under hydrostatic pressure. Pumping at the proposed Bailly Generating Station will affect primarily unit three. Thus, we conclude the pumping will affect the spririg mire area. On the other hand, the Great Marsh depends primarily on unit one water. Sealing the fly ash ponds will affect unit one water levels in varying degrees, and therefore will affect the Great Marsh to the larcest extent on the west.

To this extent the pumping at the ccnstruction pit, and the sealing of fly ash ponds can have separate effects. ,

B. Seasonal and Annual Variation ,

As already pointed out, a recurring annual pattern in water regirie is essential for maintaining wetland connunities. Sedge meadows, for example, will chance quickly in response to stabilized water levels, evolving to shrub communities, if dried, and conversely into open marsh and water if the water level is keot high (Curtis 1959, van der Valk and Davis 1979). Wetland forests respond similiarly, but more slowly (Johnson et al 1976).

Other wetlands, such as prairie ponds, adapt to alternating wet .

and dry years by maintaining seed banks which allow the community alternative strategies, depending on the season (van der Valk and e

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5 Davis). While the foregoing authors discuss several possible outcomes of water regime changes in sedge meadcws, there is very litt15 information in the literature concerning the effects of such changes on spring-mires. Kukla (1965) hypothesizcs that the area of a spring mire is related to the upward force and the volume of water in the artesian spring i

beneath thb mire. However, the vegetation of Kukla's area was mostly Schacnum and thus somewhat different fron CBitNL.

To su=arize to this point, we conclude that the proposed changes in water regime will affect the Great Marsh ecological comunity, although the magnitude of the changes' in response to the predicted ground water change are unquantifiable at this time. There is no literature on prospective changes in spring mires similiar to the one in the CEfJil.

The USGS studies (Meyer and Tucci 1979, Gillies and Lapham 1980).

do not, as yet, provide either the background for, or projections of

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the prospective changes in seasonal or annual water regime. Because it is the departure from these patterns that foretell changes to wetlands, future monitoring and modelling must establish baselines for water levels, decartures from baselines, and water chemical conditions '

associated with the mixinq of surface vs around water sources in the upper layers of the marsh.

C. Fly Ash Settling Pond effects on Unit 1 Water and the Great Marsh.

During the middle 1960's the Northern Indiana Public Service Com.-

pany installed a series of fly ash settling ponds on the north side of its properties (see Meyer and Tucci F16.15 and other reports for phy-sical setting). These ponds are designed with earthen dikes and water .

levels with a head of appruximately 8 feet above pre-1980 water l levels in conds just outside the dikes, Seali.nghassinceIcweredthepond15vels.

Cross.-sectional data continuing 1000 feet north of the ponds indicate an

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additional drop of 4 feet in the water level of the interdunal ponds.

Analysis of the unconfined surface water levels of Unit one (the uppermost aquifer in both the industrial area and the National Lakeshore) indicates modification of this aquifer by approximately three feet at the west.end of CBWC. This evidence provides partial confirmation of the USGS's' projection of a 1.6 ft. drop in ground water in the Great Marsh near the CBNNL (three feet at the west end of the surrounding wetland) as a result of sealing the fly ash ponds.

These projected decreases in water level are judged here to repre-sent the magnitude of an earlier water level increase in the wetlands following introduction of the fly ash pond seepage (2 million gals./ day, total, some portion of which follows the drainage system to the east).

Since organic materials tend to separate and cartially float upward with increases in water level, no obvious differential between the level of the new water surface and the organi,c sub-strat'e w3uld be evident either in the late 1960's or at present. Personal observations (Loucks) show that recensolidation of such materials takes place gradually, but no information is available on rates of vegetation response. The reconsolidation probably can be expected during the first two growing seasons after abatement, depending on weather conditions.

Numerous studies have shown that the princioal effects of elevated water levels similiar to those which appear to have taken place in the 1960'.s are to weaken the short, mat-forming grass, sedge and composite populationsoand induce invasion by weedy, widely dispersed aquatics such as Typha and phracmites (Redford 1978, Bedford and toucks 1980).

Several reports indicate the CBL.'C (specifically the Great Marsh) was

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/ 1 dominated by sedges as late as the 1950's (Wilhelm 1978). Sedge / grass .

l mats were described by Cressy (1928) at locations now dominated by I cat-ta.1 (Hendrickson and Wilcox 1979). These observations, supplemented by evidence that is recognizable on aerial photography available from 1938 through

• the 1950's and 1960's to the present, support a conclusion l

that the mbst dramatic changes in the vegetation of the CBWC were in-duced by the seepage from the fly ash ponds. While we know of few studies on the recovery of biological systems following abatement of flooding, we believe that height and vigor of the Tycha/phragmites mat could be reduced by nutrient limitation (due to reduced surface flows) in 5 to 10 years. Studies of long-term recovery in prairies suggests that the principal visual and structural components of the sedge meadows could be restored in 50 years, but, in the prairie, recovery of the unccmmon species takes longer.

On the other hand, a reduction in w;ater level, coupled with fire control, can lead to the spread of shrubs, such as the Spiraea tomentosa, Betula pumila, Cornus stolonifera and Salix spp. , although the species response differs depending on pil and depth of organic soil. These shrubs normally have deeper root systems than the sedge-mat species allowing increased competition under more fully aerated conditions. Alnus increases its competitive advantage in partially aerated organic soils by nitrocen fixino.  :

One interesting feature of the present vegetation is the difference in wetland species composition between the tamarack and " ellipse" areas north of the spring-mire, and the wetlands to the south of the spring-mire.

The area in the " ellipse" appears to have been significantly isolated from seasonalsurfacewaterinputs,(see,forexample,thepHof5.0repdrted

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by Kur: 'n i the 1920's for what appears to be this area). Regent data collected at the ellipse (H2ndrickson and Wilcox 1979) do not:show l

any appreciable surface.,che:nical differences, although small populatiens of the, acid-loving plants still survive in the " ellipse" area. Careful monitorin,g of surface water characteristics in this area during the growing se'ason as abatement from fly ash .nond seepage proceeds should indicate the potential for future veoetation recovery.

As mentioned earlier, the scaling of the fly ash cond can be ex-pected to reduce the three foot head in unit one water on the west end of the CBWC. This reduction in gradient should reduce the surface flows of water from west to cast over the marsh. The reduction in ficw will allow the central portions of the Great Marsh to become more oAbrotrophicandperhapsacidic. This, we believe, was its state before 1965, although the absence of fire may have influenced the trends

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by allowing the spread of Tvpha v and shrubs.

0. pumping of Unit Three Water and the Spring Mire Response The additional drawdown of approximately 1.5 feet due to pumoage and dewatering of Unit three also is likely to result in compression.

of the organic layers, particularly in and arnund the " spring mire".

However, the drawdown of the spring mire surface probably will not be of the same magnitude as the projected change in hydrostatic head. This further drying seems likely to be sufficient to induce increases in :

shrub poculations. At this time there is insufficient informatkon on the coupling between Unit one and Unit three to say where, or for how long, biologically significant water stress will influence the more sensitive spring mire species and/or stimulate shrubs. Ther$waterina

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following the proposed two growing seascns of pumpage (and during which nost specics probably veauld begin rooting at slightly greater; depth) seems likely to affect the CSNNL as much or more than the drawdown because it could take place faster.

The U)GS reports (Meyer and Tucci 1979, Gillies and Lapham 1980),

and our independent observations are consistent with the conclusion that even modest changes in water oressure and local surface regimes are significant ecologically. Changes in waters rising through organic bog deposits are clearly important for the physical and chemical land-scape, as well as for the biotic inhabitants, regardless of details of the mechanics of the aquifer. We have received the summary of the D'Appolenia study and find it is generally consistent with the USGS studies, although differing in the magnitude of predicted change. We leave the resolution of the dif ferences between the two USGS reports and

[he D' Appolonia study to further resear,ch.

The paucity of literature cn spring mire ecosystems, coupled with lack of seasonal data on the grour.d water, weakens.our ability to yrecict detailed consequences of construction cewatering on the spring mire.

l However, we confirmed the USGS and NPS observation of a hydrostatic head slightly above the organic surface in the White Cedar area of the spring mire. The possibility of this head being lowered to any level at or below the existing level of water in the mounded peat should be of considerable concern to ecosystem stability here. Conversely, should the reduction in head under the spring mire would allow it to settle, the vegetation around the edges would become more strongly influenced by Unit or water and assume the character of the surrounding Great Marsh. The hydro-static head is the physical basis that maintait.s the existence of tilis pecu-liar and interesting feature the CBNNL. Reduction in the head before thi

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10 is a workable mitigation program would constitute a negligent manage-ment practice. Furthermore,itisnotclearwhatmitigative'fr.easures, if any, would ameliorate the impacts to be transmitted via the ground water ' system III. Conclusions g og A. General

1. The fly ash pond seal and the construction dewatering are largely separate impacts, with separate consequences within the Cowles Bog Wetland Complex.

B. The Great Marsh Area of the CBWC -

1. The sealing of the fly ash pond will influence the surface water

, regime at CBWC, lowering the water level,' reducing the gradient and slowing the west to east unit cne flow.

2. The vegetation should slowly return to its pre-1955 condition

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of sedge meadow, or become a shrub carr depending on whether or not it can be burned periodically.

3. The sites in the ellipse to the north of the spring mire,Ahere acid-loving species still survive, would possibly return to a '

condition principally governed by precipitation inputs gradually reducing the dominance of Typha.

C. The Effect of Construction Dewatering on the Spring Mire

1. Construction dewatering will reduce the hydrostatic head in the spring mire and lower the ground water level there.

2. Changes in the ground water system due to construction dewatering are expected to result in gradual compaction of the peat and seasonal drying.

These chanpes will occur irregularly over time, affecting competitive dynamics and stability of the plant populations making up the.s#pring mire.

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3. Because of changes in plant comunity composition and in the rooting depth of component plants during the dewatering pe.ried, the cessation of dewatering after 18 months is likely to produce

, ef.,fects of at least equal significance. The longer the dewatering contij1ues the greater the likelihood of a significant change toward mesic ' conditions. Further, the greater the compositional change following dewatering, the more significant the additional compositional adjustment when pumping is stopped.

4. There is little literature available on the structure and functioning of spring mires. Therefore we cannot predict with confidence the magnitude and ecological in:portance of prospective changes. How-ever, the spring mire community is likely to become more mesic, (i.e. more dominated by shrubs) as a result of the dewatering process.

, D. liitigation

1. Because of the anticipated time iag between tne dewatering at the NIPSCO plant and measurad nydrologic responses at the spring mire, there could be significant ecolegical effects at the -spring nire before hydrological recovery if pumping were to be stoppe'd. Further, the detection of influence of ground water pumping on surface waters at CBWC is hindered by the absence of an appropriate water-level baseline and the capacity to predict the control of ground water on the surface water regime. Thus, monitoring at the CBNNL prov;1 des littleprotectionfromthepotentialeffectsoftheunitthheedewaterin

2. A more appropriate monitoring strategy would be to establish as many peizcmeters as may be necessary and surface vater-level guages in reascnable proximity to the ccnstruction site. Detection of change' in the quantity or quality of ground and surface water at th m

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12 locations will permit an early opportunity for anticipating grcund water responses at the National Landmark and will suggest; appropriate actions' b_ased on the monitoring and modelling.

E. F'urthey Studies *

1. We suggest the establishment of a comprehensive monitoring system which includes observations of ground and surface waters at several locations and at several levels within the hydrologic system. It should include water level and quality measures, with observations as often as needed to document seasonal changes.

2. Background monitoring stations for both the water regime and plant communities should be established throughout the Indiana Dunes National Lakeshore. Because a classic " control" area is impossible, observation stations should be frequently replicated in similiar communi ties.

3. As part of the IDNL research program, baseline measurements of the populations of selected threatened species should be established, along with measurement of chemical microhabitat properties, so that resper.ses af ter 10 to 20 years will be fully documented. Species-with high rating coefficients in Wilhelm (1978) would be acod candi-dates for such studies.

IV. Recomendation Although the infonnation base is limited, the possibility of sianificant irreversible ecological damage to the spring mire area is large enough

• that the proposed construction dewatering should be postponed until further studies are completed.

• No panel member had an opportunity to review the proposal for cont nuirg studies and therefore cannot coment on their adequacy.

13 Literature Cited Bedford, B. L.1978. Alteration in the Grcwth and Phenology of Wetiand Plants as Indicators of Environmental Change. Proceedings of the Fourth Joint Conference on Sensing Env. Poll . , Amer. Chem. Soc. Washington D.C. pp. 170-174.

Bedford, 3. 'L. and O. Loucks.1980. Changes in the Structures, Functicn, and Stability of a Wetland Ecosystem following a Sustained Perturba:icn.

Wisconsin P'ower Plant Impact Study Progress Repor't. Water Research Center University of Wisconsin.

Cook, G. S. and R. S. Jackson. 1978. The Bailey Area of Porter County Indiana.

Robert Jackson and Associates: Evanston, Illinois.

Cowles, H. C. 1899. Ecological Relations of the Vegetation on Sand Dunes of Lake Michigan. Botanical Gazette. 27:95-117, 167-202, 281-308, 361-388.

1 Cowles, H. C. 1901. The Physiographic Ecolooy of Chicago & Vicinity; A Study of the Origin, Development, and Classification of Plant Societies.

Eotanical Gazette. 31:3, pp. 145-182.

Cressy, G. B.1928. Indiana Sand Dones and Shoreline. The University of Chicago Press: Chicagc, Illinois.

Curtis, J. T. 1956. A Prairie Continuum in Wisconsin. Ecology 36:556-558.

Curti s , J. T. 195.9. The Vegetaticn of Wisconsin. University of Wisconsin Press: Madison, Wisconsin. -

D'Apoolonia. Preliminary Review, Soil Parameters Used in USGS Report 78-138.

Bailey Generating Station, Nuclear 1, Baileytown, Indiana., May 1980.

Geis, J. W. and J. L. Kee. 1977. Coastal Wetlands Along Lake Ontario and the St. Lawrence River in Jef"erson County, New York. SUNY College Environ. '

Sci. For., Syracuse, New York. p. 130.

Gillies and Lapham.1980. Reassessment of the Effects of Construction De-

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watering on Ground-Water Levels in the Cowles Unit, Indiana Dunes National Lakeshore, Indiana. Supplement to Geological Survey Water-Resources Investications78-138.

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Gosselink, J. G. and R. E. Turner.1978. The Roll of Ilydrology in Freshwater Wetland Ecosystems. Pages 63-78 in R. E. Good, D. F. Whigham and.R. L.

i I Simpson, eds. Freshwater Wetlands. Ecological Processes and Manaqcment Potential. Academic Press , New York.

lier.drickson, W. H. and D. A. Wilcox.1979. Relationship Between Some Physical Properties and the Vegetation Found in Cowles 300 National Landmark, Indiana. Second Conference on Scientific Research in the Naticnal Parks; c

l l Proceedings 26-30. November, 1979.

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14 Johnson, W. C. , R. L. Surgers , and W. R. Keamever.1976. Forest Overstory Vegetation and Environment on the Missouri River Floodplain of North Dakota. Ecol. Mang. 46(11),56-89.

--- Kurz, H. 1923. Hydrogen Icn Concentration in Relation to Ecological Factors

. Botanical Gazette,.pp. 76, 1-29.

-= Kukla, S. T.\ 1965. The Development of Spring Bogs in the Region of N. E.

Poland (Eng. Summary I. Polska). Zeszyty Probelmcwe Post. Akad Nauk Roln. Warsa'wa. 57, 481-495.

Lyon, M. W. , Jr. 1927. List of Flowering Plants and Ferns in the Dunes Stat Park 'nd Vicinity, Porter County, Indiana: American Midl. Nat. Vol.10, pp. 245-295.

Mcdonald, M. E.1955. Causes and Effects of a Die-off of Emergent Vegetatio J. Wildlife Manager 19:24-35.

Meyer, W. , and P. Tucci . January 1979. Effects of Seepage From Fly Ash Settling Ponds and Construction Dewatering on Groundwater Levels in the Cowles Unit, Indiana, Dunes National Lakeshore, Indiana U. S.

Geological Survey. Water-Resources Investigations.78-138.

Olsen, J. S.1951. Indiana Sand Dunes Preservation. Friends of our Nature, Landscape, and Indiana Department of Conservation, Division of State Parks. Mimeo p. 5.

Olsen, J. S. 1958. Rates of Successions and Soil Damages on Southern Lai.e Michigan Sand Dunes. Botanical Gazette. 1,19:125-170.

Reshkin, M. , H. Feldman, W. E. Kiefer, and C. H. Krekeler.1975. Basic Ecosystem Studies of the Indiana Dunes National Lakeshore: Inoiana University Northwest. pp.1-1 to 6-22. ,

s Shel ford, V. E.1913. Animal Communities in Temperate America. Uni versity of Chicago Press, Chicago.

Van der Valk, A. G. and C. B. Davis. 1979. A Reconstruction of the Recent Vegetational History of a Prairae Marsh, Eagle Lake Erie, From its seed bank. Agrac. Bot. 6:29-51.

Walker, B. H. and R. T. Coupland.1967. An Analysis of Vegetation-Environmt '

Relationships in Saskatchewan Sloughs. Cam. J. of Bot 46:509-522. .

Weller, H. W. 1978. Management of Freshwater Marshes for Wildlife. po. 26'7-in R. E. Good, D. F. Whinham, and R. L. Simpsnn, eds. Freshwater Wetlar Ecological Process and Management Potential. Academic Press. New York, v.

Wilhelm, G. S. 1978. Kane Cnunty Natural Area Survey. Kane County Urc.an Deve1coment Division: Geneva, Illinois.

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! Willard, B.E.1975. What Indiana Dunas Mean to Ecology. Special Paper Presented to the Annual iteeting of the Save the Dunes Council', Eeverly .

Shores, Ir. diana. November 2,1975. Mireo. p.13.  :

Willard, 0.E. 1978. Natural Instability & Baseline Studies. Proc. Fourth 1

Conference en Sensing Enviro. mental Pollutants. ACS. New Orleans. pp. 74-77.

a i

Erratum Citation Belew

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1 Geis, J. W. 1979. Shoreline Frocesses Affecting the Distribution of Uetland l

Habitat. SUNY College of Environmental Science and Forestry. Syracuse.

New York, p. 529. -

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