Dennis M. King, Ph.D.
                      Curtis C. Bohlen,Ph.D.
                    University of Maryland System,
              Center for Environmental and Estuarine Studies,.
                    , Chesapeake Biological Laboratory
                 P.O. Box 38, Solomons, Maryland 20688
                           April 1, 1994
University of Maryland, CEES Technical Report UMCEES-CBL-94-051, April 1994,
          Prepared under Cooperative Agreement Number CR818-227
                         •       with •        .                ' ...  ' •
                •   the U.S. EPA, Office of Policy'Analysis     .
       '  -                  w,ith support from           ••'..-
            EPA Region IV (Atlanta) and Region IX (San Francisco).

                       EPA  230-R-96-004               '

Southwest Region Compensation Costs

Regional Climate, Ecology, and Wetlands
      The southwestern United States, including the states of California,
Nevada, and Arizona, is characterized by great geographic, climatological, and
ecological  diversity. Climate varies from the cool Mediterranean climates of
northern California and the montane climate of the Sierras to the cool desert
of Nevada's Great Basin, and the warm, desert climates of .the Mojave and
Sonoron deserts. This climatological  diversity is Reflected in wide ecological
variation across the region, as well as  in a diversity of wetland types.
       Precipitation throughout the  region  is  either rare  and episodic or
strongly seasonal. Rainfall is most  abundant (and  most predictable) in the
northwest, with both quantity and predictability decreasing toward the south-
east. Mediterranean climates throughout much of California (with cool, wet
winters and warm, dry summers) ensure that  the soil moisture and surface
water on which wetlands depend are also strongly seasonal,,except in north-
western- forests where coastal fogs and orographic precipitation maintain rela-
tively high soil moisture levels throughout much of the year.
       In the Great Basin to the east, precipitation is generally lower (Reno,
Nevada averages 7.64 inches of rain a year, but precipitation on mountain
 ridges may be several times that), and somewhat;unpredictable, although typ-
 ically concentrated in the winter snowfall and  to a lesser extent in torrential
 summer rains. Surface waters in the Great  Basin do not flow  to the sea, but
 instead drain locally to desert lakes, playas, and sinks. Year-to-year.variation
 in precipitation is large, causing substantial interannual  variation in  water
 depth in many of the lakes, rivers, and wetlands within ihe basin.
        In  the warm deserts to  the south and east, rainfall is concentrated in
 late summer thunderstorms, although a secondary rainfall peak sometimes
 occurs during the winter.  When rainfall comes,| it often is brief and intense,
 producing flash floods, which  in turn produce geomorphically distinct  desert
 streams with their diagnostic riparian vegetation.
        Because of low and highly seasonal rainfall throughout  much  of the
 region, riparian wetlands (sensu lato) are especially  important. River and
 stream systems collect water from large areas,  import water from places with
 higher precipitation, or transport it from areas of large snow accumulation.
 They are islands of moisture in arid  or seasonally arid landscapes and thus are
 associated with most of the regions perennial water and wetlands. Small, iso-
 lated  wetlands are uncommon, except on the western slopes of mountain
 ranges, where orographic precipitation is significant. Elsewhere, isolated wet-
 lands tend to be ephemeral, appearing  after rain! events only to quickly  evapo-
  rate, sometimes for years at a time (e.g., vernal pjools, playas, and,saline lakes).
        The other major group of perennial wetlands in the region are the
  coastal wetlands of California. Because of the regions' active geology and asso-

Southwest Region Compensation Costs     ,      .                .    "   .     2 .

elated uplifting/ much of the .California coast is steep and rocky, with few shal-
low  areas in which coastal wetlands could develop. Historically, therefore,
coastal  wetlands were concentrated in  estuaries and embayment, especially
San Francisco Bay.            .                             ,
      Endangered species are significant components of wetland ecosystems
throughout the region, for a variety of reasons.

•     Because, of many thousands of years of evolution in isolated aquatic
      habitats, a relatively large number of endemic species are found in wet-
      lands and  other aquatic habitats in desert regions of the Southwest. As
      human activity has altered  the hydrology of desert springs and major
      river systems, the endemic species that  depend on them have declined,
      in many cases becoming endangered or threatened.

•     In Nevada's Great  Basin, extensive Pleistocene lakes .were replaced by
      much  smaller water bodies as evapotranspiration began-to outstrip pre-
      cipitation. Once interconnected populations of aquatic organisms have
      become  fragmented as the lakes shrank. Aquatic refugia within  the
      basin  are  often saline  and hot,  presenting an especially harsh envi-
      ronment for small aquatic  organisms.  Strong selection,  isolation, and
      thousands of years have  produced several groups of relatively young
      endemic species, sometimes adapted to very specific harsh environ-
      mental conditions.         '                      .

 •     High  degrees  of  endemism  'are  also found throughout much  of
      California, apparently the result of biogeographic isolation provided by
      surrounding mountains and- deserts. Here, too, as human activity has
      destroyed most of  the state's wetlands, and as the region's appetite .for
      water has grown,  species  dependent  on wetlands and other aquatic
      ecosystems have been hit especially hard.

 Wetland Losses
       Estuaries  and river basins  have been  favored areas for human settle-
 ments  since before the development of writing. The availability of water for
 transportation, drinking,  irrigation, and removal of wastes makes riparian ar-'
 eas and coastal estuaries especially attractive areas for human settlement.
 These areas are especially attractive in  arid landscapes, in which.water is rare
 or seasonally unavailable. Thus  human 'settlement in arid, regions  tends  to
 focus around water courses,  wetlands, and coastal embayments. Indeed," the
 impacts of humans on the wetlands of the Southwest have been substantial/
 Significant wetland losses occurred very early in the European settlement  of
 the region.1
        By the mid 1980s, wetland losses throughout the region were. substan-
 tial. California had lost  91% of its  original  wetland inheritance (more than

Southwest Region Compensation Costs

any other state) Arizona had. lost 36%, and Neva|da,-52% (Dahl 1990). While
the losses in the desert states are at or below the;national average, the losses
are notable for  two reasons. First, population densities over most  of these
states are very low (the majority of the population lives in a few urban areas).
Thus,  relatively small rural populations have paused significant  wetland
losses. Second, these states originally had relatively low percentages of their
surface area as wetland (1.3% for Arizona, 0|.7% for Nevada,  4.9%  for
California), thus wetlands were never widespread, and continued losses have
made them even less so.                                           .     ;
       Agriculture, irrigation, and  massive wate|r projects have taken their
toll on wetlands throughout the region, not only jby'directly eliminating wet-
lands, but also by degrading those that are left. Large water projects have
flooded extensive riparian areas and removed large quantities of fresh water
from river flows  throughout  the  region,  (thusj drying out  many riparian
wetlands, altering the  timing  and  severity of  peak  stream flows,  and
otherwise changing hydrologic and sediment transport characteristics of the
region's  rivers  and streams on which  remaining wetlands   depend).
Development of riparian areas for  agriculture has been extensive throughout
 the region; these areas were relatively  flat, close to water, and easily  irrigated.
 Irrigation return flows  have significantly altered  the  ecology  of rivers  and
 other surface waters by increasing concentration? of dissolved solids in river
 water. These arid-land impacts to wetlands and surface water are in addition
 to the more  widespread problems of  nutrient enrichment, sediment loading,
 and  toxic  discharges associated with  human activities throughout North
 America and the world.                 .
        Major wetland losses in California have loccurred in  the Central San
 Joaquin and Sacramento River valleys (Herbold and Moyle 1989) and in the
 San  Francisco  Bay  region (Josselyn  1983). In the  San Joaquin-Sacramento
 River  delta, many of the natural freshwater wetlands have been levied and
 drained for agriculture. The first such  levees were constructed as early as 1852,
 and the 60 largest delta islands had all been converted to  agricultural use
 before the turn of the century. Small but widespread vernal pools once found
1 throughout California's central valley were often leveled or  plowed, leading
 to the endangerment of many typical vernal pool inhabitants.
        Early losses of coastal wetlands in the San Francisco Bay region were to
 agriculture, but losses  to urban and industrial uses also,began early. Many
 former wetlands and mud flats of northern San  Francisco, San Pablo, and
 Suisun Bays were diked before the turn of the century for  agricultural pur-
 poses, especially grazing. Many still provide fodder for local dairies. Land
 speculation and  inaccurate surveys  helped drive the filling of wetlands in
  port and urban areas. Whole communities along  the coast  of San Francisco
  Bay are built on wetland fill: The tidal  marshes of the southern San Francisco
 •Bay area are naturally more saline than those in the  north,  and less suitable
  for agriculture. However, many of  the marshes  and mud flats there  were

Southwest Region Compensation Costs              .                        .4

diked for salt evaporation ponds.;The first local salt production occurred in
the 1850s. By the middle of this century, few natural marshes were left in the
southern Bay.   • •'  '       .;•-"''.-     .'-•:•
       Major wetlands losses in the desert states have Been more -widely dis-
tributed, in  part because  wetlands  were more widely distributed. Wetland
losses have been the result of agricultural development, diversions of surface
water, and pumping of groundwater (Minshal et al. 1989). Direct wetland
losses to urban development are predominately a recent phenomenon.

Regional Economic Conditions                             ,
       California's economy is large and diverse. Recent downturns in the de-
fense and aerospace industries, however,  and a series of natural disasters
have hit California hard, and the state remains mired in recession despite the
national economic upswing. Southern California, long a center  for aerospace
 and military contracting, has been especially hard hit.  The Los Angeles area
 accounted for approximately half of the jobs lost in the .state during the height
 of the recession. Property values, extremely high five years ago, have declined
by as much as 50% over the last few years, most significantly in southern
• California. California housing and construction industries  are still in a
 slump, reducing short-term pressure on the State's wetlands.
       Paradoxically, the recent L,os  Angeles earthquake may help pull
 California out of its recent economic malaise'by forcing households and busi-
 nesses to  invest in rebuilding rather than making other investments put-of-
 state. The housing  and construction industries, in particular, are expected to
 get a boost  as earthquake victims rebuild.  The influx of federal assistance to
 the region, along with the multiplier effect of the increase in construction ac-
 tivity may trigger an economic'resurgence and development throughout  the
 region. The effect  of these investments on the region's  wetland resources,
"however, remain unclear. Much will depend on the extent to which new
 construction on previously undeveloped land replaces  or is spurred along by
 the redevelopment of areas damaged by the quake.                        .
        The economic recovery was not as slow in  coming to  Arizona and
 Nevada. Arizona and Nevada have grown rapidly over the last decade or so.
 The two states have taken part in sunbelt growth made possible by the devel-
 opment of inexpensive  air conditioning and large  water projects. While
 retirement, tourism, and recreational development have been important to
 growth in both states in  the recent past, both states are making an effort to
 attract manufacturing industries as well. Most recent growth has occurred in
 and around major urban areas, a trend that is likely to  continue, and has been
 associated with large-scale land development rather than high density devel-
 opment. This has put increasing pressure on wetlands and other features of
 the -environmental landscape.    ' „.    .

Simthuvst Region Compensation Costs

Met °ThP  analysis  of  regional" wetland  creation/  restoration,  and

  na"° dtvrdaetf°atoneP We  herefore supplemented these records with cost

   engineering cost-accouiumg        ,,' u    ..• '  TAr;tVi  Qnhrontracted wetland
   '      4.-     oiects developed in collaboration witn suDcontiav.i.c\j.

 Soutltzuest Region Compensation Costs                                '       ]6

 project costs change as project size -changes and to produce estimates of per
 acre project, cost adjusted for project size. Reported results, except where
 otherwise noted, are based on hypothesis tests with p<0.05.
       There was also an extremely uneven distribution of cases within and
 among  project categories. Freshwater emergent  wetland  creation  projects
 were abundant in our .sample, for example, while projects to restore beds of
 submerged aquatic  plants were rare. This pattern, which reflects both the
 frequency  with  which  specific  wetland  types  are  restored or-"created
 nationwide, and the vagaries of data  collection, limits.the types of statistical.
• cost comparisons that are possible. The results presented here reflect the most
 complete analyses possible with the existing databases.
 Nationwide Background
       Wetland creation and restoration projects in the primary database were
 separated, into eight project categories  for analysis. These categories  include:

 (1)    Aquatic Beds, consisting of tidal or nontidal communities of  perma-
       nently or nearly permanently submerged plants;

 (2)'   Complex Projects, incorporating three or more wetland types in a
       single project;                     ''..-.'.

 (3)    -Freshwater Mixed Projects, consisting of nontidal projects in which
       both- forested and emergent vegetation is produced;

 (4)    Freshwater Forested Projects, establishing woody vegetation  (forest or
       shrub) in nontidal wetlands;

 (5)   Freshwater Emergent Projects, establishing emergent wetlands in non-
       tidal wetlands;

 (6)   Tidal Freshwater Wetlands Projects, often consisting of mixed  emer-
       gent and woody vegetation;

 (7)   Salt-marsh Projects and other marine or estuarine projects, establishing
       wetlands dominated by emergent vegetation; and

 (8)   Mangrove Projects, establishing mangrove  communities.
        Differences in the costs of restoring different types of wetlands are not
 large relative to the differences in costs within any one wetland category. This
 reflects the enormous differences in the site and project design characteristics
 within project categories-and frequent similarities among the tasks required
  to restore wetlands in different categories. Median,  mean, minimum, and
  maximum per acre creation and restoration costs  for the eight categories of

Southwest Region Compensation Costs                  |

wetland projects just described and for agricultural conversion projects (from
the secondary database) are shown in Figure 1.   .}
                                    Cost Per Acre
                              (In 1993 $; excludes land costs)


1 (

! •
" high
> mean

i median

• low
1 ? «,?,
	 -1 	 ^ 	 1 	 — 	 1 i 	 1 ; " •
1 ' 	 ^ >- /n
£ g "S "S 1 £ -e | .,
cg"g Q. J= ' § "5 5 P5 !-= 5 £
§-m£ 2£££|« S 5,
< 55 £EF||

S 0
^ , '^

"3 a)
0 >
•=: c
O) O
                                    Wetland Type
 Figure 1.  Point  estimates  and ranges of project  costs from the primary
            database for specific project categories,;

       Table 1 displays summary cost statistics by wetland category based on
 the  results of the nationwide study (primary data, except for agricultural
 conversion data). Similar, detailed breakdowns of project costs from within
 the  region itself  are potentially misleading because of small sample sizes
 National-regional comparisons are given below: The table also includes cost
 breakdowns by preconstruction, construction and postconstruction tasks, and
 by input  category  (labor, materials, equipment  and other). Region-specific
  differences discussed elsewhere in this report will effect some of these values.

 Southwest Region Compensation Costs
Table 1.       Cost Estimates and Cost Allocation (excludes land cost) From
               the National Study.

- Aquatic. Bed

. Project Costs (Thousands)
Average ' $19.5
Minimum 18.3
Maximum 21.7
Median 18.6
Sample Size' ,, 3


4.3 '
Project T\
FW ,

^pe ~

"$77,9 '

' FW





1.0 .
10.2 '
9 •


13.6 ..
".4 -


$1.0 •
Breakdown by Tasks: .
Preconstruction ' 1 7%
Construction 63
Postconstruction 20
58 .

13% '
Breakdown by Input Category: , .
Labor 58%
Materials . 8
Equipment 34 . '
Other . 0 ' ' .
10 :
63% •
•20* '•
. 0
       High end of rartge involves researching and restoring hydrology and planting; low end involves
       restoring hydrology only.  '                 .    '.

**   -   Agricultural Conversion data are derived from the secondary data. Cost breakdowns for
       agricultural conversions are based on a project consisting of hydrologic modification without
    .   planting or formal plan development.

Regional Differences—Primary Data
       Our Primary database contains  32 projects from the southwestern  re-
gion,   all from California.  Approximately half of  these projects are from
southern California and half from northern  California. Projects from the
south  were primarily  intended to produce wooded wetland  habitat  for the
Least Bell's Vireo, but we also have  data for a vernal pool creation project and
a few other emergent wetland  projects. Northern California projects were
more  diverse, including riparian  restorations, and complex wetland en-
hancement projects in estuarine-palustrine wetland complexes along the San
Francisco Estuary.       .      .'   '                              -
       An analysis of covariance  was used  to determine whether wetland cre-
ation  and restoration projects in our Primary Data from California were dif-
ferent in cost from similar projects elsewhere  in  the country. They were.
Wetland projects in .California were approximately double the cost of similar
projects elsewhere  in  the country.  A  more complete analysis, adjusting  for
wetland project type (creation,  restoration,  enhancement), shows a slightly
larger cost  difference. California projects are about  2.3 times  as .expensive as
projects elsewhere in the country.           _   '.   •  •                     .

Southwest Region Compensation Costs
                  Primary Data: Southwest vs. Other Regions
      1,000,000 T
                          Southwest (•)
 Figure 1.    Primary data—Southwest
 Regional Differences—Secondary Data
       Of our sample of 397 projects '(excluding; agricultural conversion pro-
 jects),  46 were located in the Southwest region. All but  two were from
 California. Of the 46 projects, 20 were wetland creation projects, while 5 were
 restoration, 5 enhancement, and 2 mixed projects. We could not determine
 project type for the remaining  14 projects. The frequency of wetland creation
 projects in this  sample is lower than in the rest of the database (by chi-squared
 test, X2 = 15.647, p=0.0013). Projects in the southwest were substantially larger
 than projects elsewhere in the country (t-test on log-transformed project sizes,
 t=4.034 p= 0.0001). The analysis of covariance showed no significant differ-
 ences  in per acre project costs between projects in the southwest, and those

Southiv'est Region Compensation Costs
                Secondary Data: Southwest vs. Other Regions
      10,000,000 T



            Southwest (•)

            0       _\ _ »o#
          r,000 --  Other (o)

 10 -j-
              0.001      0.01      0.1       1        10     • 100   .   1000

                                     Size (acre)

Figure 2.     Secondary data—Southwest.

      Characteristic wetland creation and restoration projects in the south-
-west United States  are determined, in part by the meteorological and ecologi-
cal conditions in the region, and in part by the -limited opportunities that exist
for restoration and the high demand for mitigation  sites. The need for wet-
land mitigation, by definition, is tied to the  level  of development  activities,
both public and private, that harm wetlands. The politics of water projects
have changed dramatically, and it appears  that  the  future will bring few
massive, federally subsidized water projects, which will limit wetland impacts
from water projects. The swampbuster provisions of the 1985 and. 1990 Farm
Bills, the wetlands reserve program, and changing  priorities  in agricultural
programs ^generally are  likely to continue a nationwide  trend away  from
destruction of wetlands  for agriculture. Urban development and  associated
highway and utility  construction,  however, in  general  keeps pace  with
development, and is likely to accelerate as  the current economic recovery
expands throughout the Southwest.
       All three states have very low percentages  of their land area in wet-
lands (0.4% in California, 0.8% in Arizona, 0.3% in Nevada), which in princi-
ple should make avoidance of wetland impacts easier than in  states with a
higher percentage of the land in wetland. However, many of the region's
metropolitan areas are near rivers and the  sea,, so  much wetland  develop-
.ment will continue to be in areas with higher-than-average concentrations of
wetland. Many wetland impacts will come from linear projects like road and

Southwest Region Compensation Costs
utility construction that must cross waterways in order to fulfill their basic
purpose. Demand for mitigation may also be increased by endangered species
impacts, some of which will be mitigated through creation or restoration of
wetland.                                       ;
       Restoration outside of the context of mitigation is likely to remain less
common  in the Southwest than elsewhere in the country. Regional demand
for water withdrawn from rivers  and stream systems  for human uses  has
grown explosively over the last several  decades;. Reserving water from  hu-
man distribution for environmental purposes will prove expensive,  legally
difficult,  and politically  unpopular.  However, without available  water,
restoration of many former wetland areas will be difficult or impossible,  and
those restoration projects that are possible will be relatively complex a'nd ex-
pensive.  The Southwest has relatively few opportunities to pursue the kind
of inexpensive agricultural conversions that have proven so successful in the
Midwest  and those few opportunities are relatively expensive, as agricultural
conversions go. In northern California, and along the coast, where restoration
 is not hindered by  a lack of  water, property  values  are high, and many
 degraded or converted wetlands are in profitable use for agriculture or salt
 evaporation. Acquiring permission to  restore wetlands  on  these lands, or
 outright  acquisition of restoration sites' in these  areas are  likely to be
 expensive.  Restoration and enhancement projects  outside  the  context of
 mitigation is likely to continue to focus on lands  held by local, state, or, federal
 governments, and on riparian restorations that can be carried out without
 removing large areas of land from existing profitable uses.
        Regional  climate conditions and the history of human use of the  land
 combine to make typical wetland creation and restoration projects through-
 out the Southwest unusually complex, and therefore expensive. The regional
 context  for wetland restoration in the Southwest can be summarized as fol-
 lows:                                  .      ;                    , -
 (1)    Wetland  creation and restoration projects in  the region face  unusual
        technical challenges because of a lack of available surface water. Careful
        planning, engineering, and construction  are often necessary to ensure
        simultaneous compliance with  storm  Water management  require-
        ments and provision of adequate water supplies -for the wetland itself.
                                             "1         -
  (2)    Many wetland creation  and restoration projects are undertaken, in part
        to satisfy requirements for mitigation of losses  of endangered species
        habitat (e.g.,  the San Diego Mesa Mint, Light Footed Clapper Rail, and
        Least Bell's Vireo). Endangered species compliance  increases project
        complexity, as well as monitoring and follow-up costs, and greatly in-
        creases project costs.             •    .   1

   (3)   The concentration of wetland impacts in and around urban areas.also
         increases project complexity. Creation or; restoration of natural or semi-

Southtoest Region Compensation Costs                                      12

      natural wetlands  in or  near urban centers is  especially challenging.
      While  this is especially  true of freshwater wetlands,  for which provi-
      sion of appropriate hydrologic conditions.may be impossible in an ur-
      banized watershed, an urban,context also increases the difficulty of tidal
      •restorations and limits the ability to restore populations of plant polli-
 ,,    nators, predators, and .other key ecosystem links. -

(4)    Project complexity may also be increased by the preponderance of ripar-
   '  • ian wetlands in the desert parts of the region. Riparian restorations can
      ,be expensive because of the complex engineering  sometimes  required
      to ensure stable channels in flowing water systems. Restoration of low-
      flow wetland systems seldom requires as much engineering expertise
      as  flood-prone riparian systems.  Unfortunately,  it is difficult  to
      compare  the  costs  of  riparian, restorations  and  typical  wetland
      restoration, since  the size of riparian restorations is more often  and
      more appropriately measured by  linear  stream  length .and stream
      discharge, rather than area.

(5)    Where restoration of coastal wetlands is  undertaken, simple plantings
     • are seldom sufficient. Restoration efforts often  must  take into consid-
      eration extensive  hydrologic modifications that have occurred in  the
      Southwest over nearly  150  years of  development activity in the re-
      gion's  wetlands.  A  majority of the  restoration  and enhancement pro-
      jects from the region in  our  Primary database included substantial hy-
      drologic modification, such as installation, of  culverts, re-establishment
      of tidal guts, and so  on!                             ,          •

(6)    Project costs throughout much of the region are also inflated because
      labor and equipment costs tend to  be higher than those found in the
    .  rest of, the country. Construction costs in 12 California cities, as well as
      in Reno and Las Vegas, Nevada, are slightly above the average for cities
      nationwide (Smit and Waier 1991). The construction cost differential in
      California varied from 7%  above  average  in Vallejo to  25% above
      average in San Francisco. In  Las Vegas and Reno, construction typically
    .  costs 3% and 4%  higher  than  the  national  average, respectively.
      Construction costs in Arizona are 8% (Tucson)  or  9% (Phoenix) below
      national averages.

Southwest Region Compensation Costs
Dahl, T. E. 1990. Wetland Losses in the United States 1780's to 1980's. U.S.
      Department of the Interior,  Fish and Wildlife Service, Washington,
      DC,21pp.                               I
Herbold, B., and P. B. Movie. 1989. The Ecology of: the Sacramento-San Joaquin
      Delta: A Community Profile.  U.S. Department of the Interior, Fish and
      Wildlife Service Biological Report 85 (7.22). Washington, DC, xi + 106
Josselyn, M.  1983.  The Ecology of San Francisco. Bay  Tidal Marshes: A
      ^Community Profile. U.S. Department of the Interior, Fish and Wildlife
      Service, Division of Biological Services, FWS/OBST83/23. Washington
      DC, 102 pp.                            "I
Kiner D M and C. C.  Bohlen. 1994a. Making  Sense of Wetland Restoration
    °' Costs.  CEES  Technical Report UMCEESrCBL-94-045,  January  1994.
      University of Maryland, Center for Environmental and Estuarine
      Studies, Horn Point, MD.
King, D. M.  and C. C. Bohlen. 1994b. A Technical Summary of Wetland
     ' Restoration Costs  in the Continental United  States. CEES Technical
      Report  UMCEES-CBL-94-048, April 1994. University  of Maryland,
      Center for Environmental and Estuarine  Studies, Horn Point, MD.
Minshal, G. W., S. E: Jensen, and W. S. Platts. 1989. The Ecology of Stream and
       Riparian Habitats  of the Great Basin Region: A Community Profile.
       U.S. Department of  the Interior, Fish and Wildlife Service, Biological
       Report 85(7.24). Washington, DC, 142 pp.
 Smit, K., and P. Waier, eds. 1991. Means Landscape Cost Data. Kingston, MA:
       R. S. Means Co.          -   .

Southwest Region Compensation Costs
      The following analysis of covariance tables provide statisticaldetails for
the conclusions presented in the  main text. All analyses were performed on
logio-transfofmed data. The  tables show partial sums of square and F ratios,
testing.the hypothesis that the particular source of variation is associated with
more of the variability in cost among projects than can be, accounted for by
chance.               .'                              .   ' .           .

Table A.I.   Analysis of Covariance for  the  Primary Data Comparing
            Southwestern Wetland Projects and Projects from other Regions
            of the Country.
ANCOVA Table ,
Logio(Acres) .
Logio(Acre)* Region
Error .-
- 1
Sum of
7.21831 '
F Ratio
5.3702 '
' 0.0000 >
0.0000 '
Parameter Estimates. - •

Std Error

Least Sq.
Std Error
Table A.2.   Analysis of Covariance for the Secondary Data  Comparing
             Southwestern Wetland Projects and Projects from other Regions
             of the Country
Log10(Acre)* Region
. 1
Sum of
F Ratio
1.9529 .
o.oodo ;
Parameter Estimates

Southwestern • •
Std Error

Least Sq.
, Mean
4.5686 .
Std Error
- 351