Diagnostic study of three lakes in southern Haiti 1 Diagnostic study of the lakes Laborde (or Lake Cocoyer), Lachaux, and Douat to identify zones of protection. Dr. Donald Huggins and Debra Baker Kansas Biological Survey Report #181 Submitted 29 May 2015 to Comité Interministériel d’Aménagement du Territoire Kansas Biological Survey University of Kansas 2101 Constant Ave. Lawrence, Kansas 66047 USA
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Diagnostic study of the lakes Laborde (or Lake Cocoyer ......hanging valleys often lack a distinct surface water connection to the lower main valley or valleys because surface flows
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Diagnostic study of three lakes in southern Haiti 1
Diagnostic study of the lakes Laborde (or Lake Cocoyer), Lachaux, and
Douat to identify zones of protection.
Dr. Donald Huggins and Debra Baker
Kansas Biological Survey Report #181
Submitted 29 May 2015
to
Comité Interministériel d’Aménagement du Territoire
Kansas Biological Survey
University of Kansas
2101 Constant Ave.
Lawrence, Kansas 66047 USA
Diagnostic study of three lakes in southern Haiti 2
Diagnostic study of three lakes in southern Haiti 10
characteristic of karst regions, much of the precipitation in this region enters the hydrologic
cycle by vertical movement into the subsurface through joints and solution features.
Lakes and Lake Watersheds
The oldest reference to Etang Lachaux that we found was from a 1934 expedition by P.J.
Darlington Jr. to collect ground insects. He said “On October 26th and again on the 27th I
collected along the shores of Etang Lachaux, a fine, small lake an hour's walk over a ridge east
of Camp Perrin. This was perhaps the best single locality I found below 1,000 ft. for ground
collecting.” This paints a picture of a vegetated landscape surrounding the lake at the time of
Darlington’s expedition. Now all that remains are few large trees, shrubby plants, and crops
such as corn planted up to the receding lake edge and on the hillsides overlooking the lake. As
with much of Haiti, deforestation has led to bare hillsides prone to erosion during heavy rains.
To our knowledge there are no published accounts describing the historic or even more current
(1940s to 1990s) landscape characteristics and land use within the watersheds draining Etang
Douat or Laborde.
While the land use and land cover of these watersheds is only vaguely documented, it seems
safe to assume that they were historically forested but have suffered from continuous
deforestation and intensive agricultural grazing and cultivation. As of the date of this report
these watersheds continue to suffer from massive, basin-wide erosion with little or no
organized or programmatic efforts to contain or reduce soil erosion and instill land
management practices.
These karst watersheds are typical of the karst landscape of the southern peninsula and as such
share similar topographic, geological and soil characteristics. Soils are predominately Udepts –
new, shallow soils associated with forests. In many areas of these watersheds, these thin,
exposed forest soils have quickly eroded from the high-slope terrain that characterizes all the
watersheds in this mountainous region. It should be noted that karst environments such as
these watersheds have been recognized as important landscape worthy of protection (Day
2011). Karst landscapes play a critical part in water conservation and the maintenance of
biodiversity and much of the world’s karst areas lay within developing countries like Haiti. Day
(2011) lists a number of reasons for the protection and preservation of karst landscapes. They
include: 1) important areas for scientific study across a variety of disciplines; 2) religious and
spiritual areas; 3) areas of specialized agriculture and industry; 4) critical areas to the
understanding of regional hydrology; 5) recreation and tourism areas with important economic
and aesthetic value; 6) habitats for endangered species of flora and fauna; 7) areas possessing
rare minerals and/or unique landscape features; and 8) important historic and prehistoric areas
with cultural importance. Only about one percent of the karst regions in Haiti is offered some
level of protection from human impacts and land use changes (Kueny and Day 1998).
Diagnostic study of three lakes in southern Haiti 11
Recognizing the importance of karst landscapes, and their protection in Haiti, adds incentive to
the protection of these study lakes thus assuring the simultaneous protection of these karst
watersheds.
Much of what we know about these watersheds comes from two primary published sources – a
2007 thesis by Jean-Louis Enold and a 2012 land use and land cover baseline report produced
by The Earth Institute, Columbia University in partnership with Catholic Relief Services and the
Organization for the Rehabilitation of the Environment (ORE), Haiti. Enold’s thesis
concentrated on landownership, erosion, agriculture uses and management practices within
the Laborde watershed. Both of these publications proved of value and are cited on a number
of occasions in reference to general observations in some or all of our study watersheds and
lakes. However, we have used our own estimates of a number of lake characteristics and
watershed features since our methods and techniques provide more pertinent accuracy and
precision than that of Enold’s and the Earth Institute reports.
During the last 60 years (± 10 years) water level of all of these lakes has been reported to
fluctuate from local flood to near dry conditions (personal communications, Lachaux, Douat and
Laborde community meetings, March 2015). The current study and the past study of Lachaux
were both conducted during low water level and rainfall conditions as noted by local authorities
and the historic rainfall records of ORE (Table 1). The average rainfall in 2013 and 2014 was 136
and 167 cm, about 32% less than the previous 20 year average with 2013 having the lowest
rainfall on record for Camp Perrin. Thus it should be noted that study results may not represent
typical lake conditions due to the drought-like conditions that preceded lake sampling events.
Table 1. Watershed and lake size (square meters) at and before the time of this study. Watershed area was determined from boundaries created in GIS from ASTER GDEM source data (see Appendix A for details). 2011 lake area was determined from Earth Institute (2012) landuse/landcover calculations. 2013 – 2014 lake area was determined by authors by recording lake perimeters while walking with handheld GPS unit.
Lake Etang Lachaux Etang Douat Etang Laborde
2011 lake area m2 585,874 119,246 470,504
2013 May lake area m2 539,361 -- --
2014 January lake area m2 -- -- 389,346
2015 March lake area m2 676,252 0 363,744
Watershed area m2 3,684,745 2,710,137 7,128,851
Low-water and no water lake conditions as experienced in our studies also impacts land use
and land management practices that more directly affect the lake ecosystem and water quality.
Diagnostic study of three lakes in southern Haiti 12
While general land use within each watershed is thought to be fairly similar from year to year,
the area immediately surrounding the lakes dramatically changes during low and no water
conditions. Farmers nearest the lake and with access to the lake bottom lands exposed by
decreasing water levels immediately put the exposed lake bottom into production. The
increase in agriculture cultivation around and in the lake basin is also accompanied by great
livestock use of the lake for both forage and drinking water. Both the increased livestock access
and increased cultivation in and near the lake bottom decrease biological and water quality.
The use of the lake basin and bottom areas (during drought conditions) in each lake are very
similar as is the general land use and practices noted in each watershed (Table 2). The actual
land uses within each watershed are very similar when the highly fluctuating water category
(i.e. lake surface area) is removed with the biggest differences in watershed land use occurring
in the “other” category and agricultural cultivation (i.e. Cultures Agricoles). The Lachaux
watershed has about 25 % less cultivation in it than the Laborde watershed which might affect
water quality except that portions of each watershed drain to and through large alluvial fans
(e.g. alluvial plains) which are functioning to reduce sediment delivery and associated
containments directly to each lake. This suspected phenomenon is discussed in the
recommendations section of the report. In summary, it appears that watershed-wide (i.e.
basin-wide) land use and land cover are extremely similar, thus impacts from land uses should
be similar except for affects related to near lake land slope, farming and buffer conditions.
Table 2. Percent land use and land cover as determined from 2011 data provided by Earth
Institute, calculated after removing the water category from the total percentage. Total
watershed area estimates do include the water land cover category. See Earth Institute report
(2012) for land use definitions.
Land use category Etang Lachaux Etang Douat Etang Laborde
Total watershed (Bassin versant) (m2) 3,684,745 2,710,137 7,128,851
Diagnostic study of three lakes in southern Haiti 13
Figure 5. Etang Lachaux showing sampling sites in white, and depths (cm) of two sites in yellow.
Watershed boundary is represented by a blue line.
Diagnostic study of three lakes in southern Haiti 14
Figure 6. Etang Douat showing locations of a residual pool of water (D_hole), cave opening, and
the hibiscus bramble pictured in Figure 6. Watershed boundary is represented by a blue line.
Aerial photo shows water but basin did not contain water during the month of the study.
Diagnostic study of three lakes in southern Haiti 15
Figure 7. Etang Laborde showing sampling sites in white and depths (cm) of three sites in
yellow. #1 is hand dug well #1, #2 is hand dug well #2, NGO well is a pump well. Watershed
boundary is represented by a blue line.
Diagnostic study of three lakes in southern Haiti 16
Study Objective
Our objective was to perform a baseline ecological assessment of Etang Laborde, Etang Douat,
and Etang Lachaux in the South Department of Haiti (Fig. 5 - 7) and offer suggestions for zones
of protection. Water quality measurements included in situ measurements and bacteria and
nutrients from samples returned to the laboratory. We performed a complete biological
assessment (bioassessment) including using quantitative methods to collect representative
samples of the macroinvertebrates, zooplankton, and phytoplankton populations.
Phytoplankton enumeration will be used to estimate productivity within the lakes. We
collected representative taxa from the aquatic macrophyte communities. We examined the
fish population using catch and release methods, and collected representative taxa for
identification. Samples were collected both from the lake shore and from throughout the lake
accessed via an inflatable boat. We walked (Douat and Laborde) or drove (Lachaux) to the top
of the largest gullies of each lake to evaluate watershed land use and land cover, and collected
macroinvertebrates, fish, and water samples from wells, springs, and stream pools we
encountered. To reconstruct a 50-year history of watershed land use, we concluded work at
each lake with a community meeting of residents who live near the lakes. A workshop was held
at ORE with a group of stakeholders chosen by CIAT and ORE to learn more about their
understanding and goals for this watershed and share initial results of the study.
Methods
This study spanned 9 – 19 March 2015. On the first day of the study at each lake, we evaluated
land use practices and vegetative cover, and familiarized ourselves with lake conditions by
walking around the lake to collect macroinvertebrates and water chemistry from 3 shore
locations and plant specimens to characterize the macrophyte communities. On the second
day we took an inflatable boat on the lake to collect 3 water chemistry samples in conjunction
with 3 phytoplankton and zooplankton samples. We also measured lake depth, Secchi depth,
and in situ water chemistry from these 3 sites and an additional 8 to 12 sites distributed
throughout the lake. On the third day we meet with residents to inquire of the history of lake
and surrounding land use. See Appendix B for sample locations.
Etang Douat had no water, affording us an extra day to explore and document conditions in the
larger watershed of Etang Laborde. We also spent a morning examining the location, number
and condition of culverts along National Highway 7 where it drains to the watershed of Etang
Lachaux on the west and north. Qualitative collections of macroinvertebrates and fish were
collected from a stream in the Douat watershed, while in situ water measurements and water
samples were collected from springs and wells in each watershed. The geographic coordinates
of all sampling localities were recorded with a handheld GPS. Import permits for biological
samples were obtained from APHIS and USFWS. Export permits for these same samples were
obtained from the Haitian government with the help of CIAT after a quarantine period.
Diagnostic study of three lakes in southern Haiti 17
Land use and land cover (LULC) of watersheds
We delineated the watershed of each lake from ASTER GDEM source data (see Appendix A for
details). Additionally, we obtained LULC maps of the watersheds produced in 2011 by the Earth
Institute at Columbia University for UNOPS and UNEP (Appendix F). Their methods are
described in their September 2012 report (Earth Institute 2012). The maps are in jpg form thus
not compatible for analysis in ArcMap. We have made a request to UNEP for the raw shapefiles
of the LULC so that we can overlay the LULC with topography and determine areas where
agricultural or bare ground overlap steep (>50%) slopes. These areas of high erosion are the
most likely candidates for zones of protection.
LULC was verified while walking the watershed and observational notes were made. We also asked residents of the lake about the history of their use of the lake and land, and changes they would like to see, if any. Questions included flooding and drought history, fish occurrences, past tree planting efforts, and preferred use of the lake land. The population of each watershed was estimated by counting the number of houses that show in Google Earth aerial photos and photographs that we took, and multiplying this number by 5 (Cayemittes et al. 2007 report average rural household size at 4.7 people). The thesis by Enold (2007) contains extensive information about the population demographics and land ownership and practices in the Laborde watershed.
Water level, Secchi depth, in situ water chemistry
At 11 – 15 locations distributed throughout each lake we determined water depth, Secchi depth
and measured in situ water chemistry with a Horiba U-22 water quality probe that was 2-point
calibrated prior to each sampling day. In situ measurements included pH, turbidity,
conductivity, salinity, oxidation reduction potential (ORP), temperature, and dissolved oxygen.
Time of each measurement was recorded.
Nutrients and bacteria
To determine nitrogen, phosphorus, and the presence of Escherichia coli and other coliform
bacteria, grab samples were collected at 3 of the on-lake sites, 3 shoreline sites, and at all wells
and springs that we encountered. Within 9 hours of collection, samples were returned to our
Haiti residence and 1 ml of each was placed on a 3M Petrifilm plate and incubated for 12-15
hours against the body (Metcalf 2010). E. coli appear as blue colonies, while other coliform
appear as red colonies with gas bubbles.
Also with 9 hours of collection water samples were analyzed with a HACH DR700 portable
colorimeter for ammonia, total phosphorus, and nitrate. The low-range nitrate method has a
detection range of 0 to 0.5 and limit of detection of 0.024 mg/L as NO3-N. Ammonia nitrogen
test is based on the modified salicylate method (Reardon et. al. 1966) with a detection range of
0 - 1 ml/L and a detection limit of 0.029 mg/L NH3 as N. Total phosphorus concentrations were
Diagnostic study of three lakes in southern Haiti 18
determined using Hach’s Ascorbic Acid method (range 0 – 2.5 mg/L PO4) to determine reactive
phosphorus after acid persulfate digestion. This procedure is equivalent to USEPA method
365.2 and Standard Method 4500-P-E for wastewater with a calculated detection limit of about
0.020 mg/L PO4.
However, no nitrate samples could be analyzed using the Hach colorimeter as the nitrate
module for the colorimeter was found to be faulty. In addition, before we sampled Laborde,
the HACH colorimeter LED display failed so all samples were acid preserved (pH 2) and
returned to the US for analysis by the Johnson County Wastewater Water Quality Laboratory
(Olathe, KS) (JOCO). Samples were analyzed on April 1-2, 2015 (within the 28 day holding time)
for Kjeldahl nitrogen as N (0.5 mg/l detection limit), nitrate + nitrite as N (0.02 mg/l detection
limit), and total phosphorus as P (0.05 mg/l detection limit) by JOCO. This water quality testing
laboratory is nationally certified under the National Environmental Laboratory Accreditation
Conference (NELAC). In addition, some Lachaux and Douat water samples were brought back
and analyzed by the Johnson County Laboratory as a check against onsite determinations.
Macroinvertebrates
Macroinvertebrates were collected with a 500 m mesh D net using a 2 m sweep from a variety
of habitats at each of 3 sites along the lake shore. Samples were placed in 25ml screw-top
scintillation vials, preserved with 5% formalin, and transferred to approximately 80% alcohol 2 –
3 weeks later. Macroinvertebrates were returned to the Kansas Biological Survey at the
University of Kansas for identification to the lowest taxonomic level feasible. Proportion
estimates of abundance will also be calculated.
Plankton
At the same 3 on-lake water sample sites, zooplankton samples were collected using an 8 inch
(20. 3 cm) diameter by 20 inch (50.8cm) long standard plankton net with a 153 m mesh
opening. Samples of each lake were compiled into 250ml vials and preserved with alcohol.
Zooplankton tow lengths were recorded so that community metrics can be reported as units
per volume. Zooplankton samples were preserved in 80% ethyl alcohol and returned to the
Kansas Biological Survey lab for identification and enumeration.
At these same 3 sites, 80 ml of surface water was collected and compiled into a 250ml vial for
phytoplankton. Samples were preserved with Lugol’s iodine solution. Lugol's solution was
added to achieve an approximate 1% preservative concentration. These phytoplankton
samples were also returned to the Kansas Biological Survey lab for identification and
enumeration. Again, phytoplankton measures will be reported as units per volume, and will be
used as a measure of productivity within the lakes.
Diagnostic study of three lakes in southern Haiti 19
Fish
Fish community composition was assessed using a variety of collecting techniques: shoreline
seining, setting baited crab nets (2) out for approximately 4 hours, and a 4-hour set using an
experimental gill net. Seining was done using a polyethylene minnow seine net (1/4-inch (0.635
cm) mesh, 4 foot (1.22m) deep by 8 foot (2.44m) long) using repeated seine hauls along a 100
to 500 meter strip of the shoreline. Crab nets were baited with oat meal and anchored in about
0.5 meter of water depth while the experimental gill net was set in > one meter of water
whenever possible. The gill net was 60 foot (18.3 m) long and consisted of five 12 foot panels of
0.5-inch, 1.0-inch, 1.5-inch, 2-inch and 3-inch mesh openings (made by Miller Net Company).
The lakes were actively used by people and livestock, so both crab nets and the gill net could
not be left un-attended which accounted for the 4-hour set period.
DNA samples were collected from about 10 fish at each site, placed in 100% ethyl alcohol, and
returned to the KU Biodiversity Institute for processing and identifications. Each fish was
photographed and retained as a voucher. We also retained 20-30 fish representing all taxa
encountered. These fish were preserved on ± 5% formalin and returned to the University of
Kansas for identification.
Macrophytes
The more dominate and commonly occurring aquatic and semiaquatic plants were collected
and general abundances noted so that some general statements could be made regarding their
importance to the lake community. Plant specimens were hand collected, dried in plant presses
and returned to Kansas University for final determination. Photos of collected plants were
taken at the collecting sites as a record of their occurrence and to provide images of live
material to aid identification. Plant identifications were made by staff at McGregor Herbarium
at the University of Kansas.
Results
Bacteria
The presence of Escherichia coli has more to do with the possible human health issues
associated with primary and secondary contact with lake water than it does with ecological
health of the lake. A simple test for recent fecal contamination of water is to determine the
level of E. coli bacteria colonies present in the water. E. coli is present in the feces of humans
and other mammals. It slowly dies without multiplying once it leaves the body, but it survives
in water as long as the bacteria that cause typhoid fever, cholera, and dysentery. Therefore,
the presence of E. coli indicates recent fecal contamination and possible presence of these
other disease causing bacteria. On the Petrifilm plates, E. coli colonies are blue, non E. coli
coliform colonies (not associated with fecal contamination) are red with gas bubbles, and non-
Diagnostic study of three lakes in southern Haiti 20
coliform Gram negative bacteria form red colonies without gas bubbles. (Metcalf and Stordal
2010).
We tested for E. coli using 1 ml of water on a 3M Petrifilm plate. Most of the water sources
tested contained E. coli bacteria. Only a pump well at Laborde installed by an Indian NGO
produced no bacteria colonies on the Petrifilm plate (this well was retested to confirm that
there was no bacteria).
One approach to the interpretation of our Petrifilm test results is the comparison between E.
coli counts and relative disease risks such as those offered by the World Health Organization
(WHO) (Table 3). The E. coli counts at or above 10 colonies per milliliter were confined to the
small pool that was all that remained of water in Etang Douat, and in Laborde watershed a
spring run and a hand dug well along the lake shore (Tables 4 and 5). However, the USEPA
Puerto Rico Water Quality Standards Regulation (August 2014) list 2 E. coli colonies per 1 ml as
the maximum limit. Most of the non-lake samples exceeded this limit, while only 2 of the 12
lake samples exceeded the limit. These results were not surprising in light of the amount of
free ranging livestock observed in and around these water bodies.
Table 3. Correlation of Escherichia coli levels with WHO disease risk categories (Metcalf 2010).
Level of E. coli WHO disease risk levela WHO action priority MSF actionb
1-10 in 1 ml High Urgent Must be treated
>10 in 1 lm Very High Urgent Reject or thoroughly treat aWHO/UNICEF: A Toolkit for Monitoring and Evaluating Household Water Treatment and Safe Storage Programmes
(2012), Figure A-1, p.62. bMédecins Sans Frontières (1994) Public Health Engineering in Emergency Situation. Médecins Sans Frontières:
Paris.
Diagnostic study of three lakes in southern Haiti 21
Table 4. Lake water chemistry, depth, and bacteria. Shore samples (S) were collected about 1 m out from shore. Remainder (L) were
collected from a boat. 2013 was collected in May with depths from 10 sites and in situ measurement from 19 near shore sites. HACH - HACH
DR700 portable colorimeter. JOCO - Johnson County Kansas Wastewater Water Quality Laboratory. EPA standards (stds) are for Puerto Rico
surface waters (EPA 2014).
*Sum of [Kjeldahl nitrogen as N mg/l] and [nitrate + nitrite as N mg/l]
Diagnostic study of three lakes in southern Haiti 29
Table 10. Macrophytes collected during this study with Etang Lachaux or Laborde indicated.
None of these taxa are endemic to Haiti. See Appendix E for photos.
Family Scientific name Creole name English name Lachaux Laborde
Alismataceae Sagittaria lancifolia L.
Bulltongue
arrowhead x
Araceae Pistia stratiotes L. Water lettuce x
Ceratophyllaceae Ceratophyllum demersum L. Limon femèl Coontail x x
Cyperaceae Cyperus odoratus L. Fragrant flatsedge
x
Cyperaceae Cyperus sp. Sedge
x
Cyperaceae
Eleocharis interstincta (Vahl)
Roem. & Schult. Knotted spikerush x
Cyperaceae Fimbristylis miliacea (L.) Vahl Fimbry
x
Cyperaceae
Schoenoplectus tabernaemontani
(C.C. Gmel.) Palla Softstem bullrush x
Menyanthaceae Nymphoides indica (L.) Kuntze Water snowflake x x
Najadaceae Najas marina L. Limon mal Spiny water nymph x
Nymphaeaceae Nymphaea rudgeana G. Mey. Rudge's waterlily x
Onagraceae Ludwigia sp. (sterile) Primrose-willow x x
Polygonaceae Persicaria punctata (Elliott) Small Piman dlo Dotted smartweed x x
Typhaceae Typha* Cattail x x
*Not collected, photos only.
While we did not attempt to collect non-macrophytes, we did collect two plants of interest at
Douat, a rice plant and a hibiscus. The hibiscus was of concern because of it brambly nature
and our concern that it could be invasive, or at least difficult to control (Figure 9).
Diagnostic study of three lakes in southern Haiti 30
Figure 9. Thicket of Hibiscus trilobus growing along the basin of Etang Douat.
Landuse/landcover
While we were not able to obtain shapefiles of the Earth Institute’s 2011 landuse/landcover
watershed maps so that we could perform more detailed GIS analyses (Appendix F), we did
examine the maps while we walked the watershed, and found that the LU/LC generally agreed
with the coverage indicated in the maps. However, the high mix of agriculture, agroforestry,
and pasture seemed to render these coverages indistinct from each other, as most agriculture
plots on the hill slopes were sparse with crops, pasture was sparse with grass, and agroforestry
had scattered shrubs at best (Fig. 10). At the lake edges agriculture was more intense, as water
from the lakes could be used to irrigate the crops (Fig. 10 – 13).
The more densely wooded areas in the watersheds corresponded with the forestry cover in the
EI maps that defined forest as >40% canopy cover. However, these areas consisted of narrow
bands of cultured trees such as kasya (Senna siamea), sèd (Cedrela odorata), trompette
(Schefflera morototoni), and castor (Ricinus communis) and were not native tropical forest trees
(Fig. 10).
Diagnostic study of three lakes in southern Haiti 31
Figure 10. Photograph facing east and overlooking the northwest corner Etang Lachaux. A strip
of forest cover can be seen in the lower left quadrant of this photo, while intensive agriculture
can be seen along the northwest shore of the lake at the center of the photo. The remainder of
the landscape was classified as a mix of agriculture, agroforestry, and pasture. See Appendix F
for the land use/land cover map of this lake.
Diagnostic study of three lakes in southern Haiti 32
Figure 11. A mix of squash, okra, and corn near the south edge of Etang Laborde.
Diagnostic study of three lakes in southern Haiti 33
Figure 12. Crops irrigated along the south edge of Etang Laborde. Photograph taken facing
north.
Diagnostic study of three lakes in southern Haiti 34
Figure 13. The dry basin of Etang Douat, facing northwest. A residual pool of water can be
seen left of center.
Slope
Using ArcMap 10.2 the KBS KARS program calculated slope of the land within each watershed
(see Appendix A for methods) and created watershed maps with slope categorized as 30-40%,
40-50%, and greater than 50% (Fig. 14 – 16). Areas of high slope (>30%) should be priority in
protection or restoration since more runoff and erosion will come from disturbed areas of
greater slope. The relatively coarse resolution (30x30m) of the elevation dataset (ASTER
GDEM) used to calculate slopes results in an apparent flattening of the terrain, and thus
underestimates slopes. However, the resulting maps still provide guidance in selecting areas of
protection and restoration.
Diagnostic study of three lakes in southern Haiti 35
Figure 14. Slope within the watershed (black outline) of Etang Lachaux. Yellow = 30-40% slope,
orange = 40-50% slope, and red = > 50% slope. Light gray indicates the upper watersheds that
drain to the alluvial plains located above the lake.
Diagnostic study of three lakes in southern Haiti 36
Figure 15. Slope within the watershed (black outline) of Etang Douat. Yellow = 30-40% slope,
orange = 40-50% slope, and red = > 50% slope. Light gray indicates the upper watershed that
drains to the alluvial plain located above the lake.
Diagnostic study of three lakes in southern Haiti 37
Figure 16. Slope within the watershed (black outline) of Etang Laborde. Yellow = 30-40% slope,
orange = 40-50% slope, and red = > 50% slope. Light gray indicates the upper watershed that
drains to the alluvial plain located above the lake.
Diagnostic study of three lakes in southern Haiti 38
Population
Only one house was observed in the Lachaux watershed, in the northwest area of the
watershed, between the lake and the new highway. Most of the houses near this lake are
south of the lake, downhill from the lake. In the Douat watershed, approximately 7 houses are
located along the gullies that drain from the west and north sides of the watershed. Many
more houses are in the Laborde watershed. Enold (2007) reports the population of the Laborde
watershed at 1,680 (280 households x 6 people), and his estimated watershed size of 7.112 km2
was slightly smaller than the 7.129 km2 we calculated in ArcMap . We adjusted this population
for consistency with the Cayemittes et al. 2007 estimate of 5 people per rural household (Table
11).
Table 11. Estimated population in the lake watersheds.
Lachaux Douat Laborde
Population 5 35 1400
Community meetings
After walking the watershed and collecting water and biological samples, we met with the
residents of each watershed, with the goal of learning more about the 50-year history of
change within the watersheds including changes in the land use, reforestation projects, land
management projects and lake changes. The number of attendees varied between watershed
communities, with a low of 9 at Etang Laborde on a day that it was raining, to a high of 89 at
Etang Douat, where school children attended the meeting. A number of people over 50 years
of age attended the meetings (Table 12). Discussion was translated by Mr. Ralph Gustave. Our
inquiries focused on a variety of topic including but not limited to extreme flood and drought
events, introduction of fish, tree planting efforts, and how residents wish the lake area to be
used. Opportunities were provided for community attendees to ask project personal questions
regarding our studies of the lakes and watersheds.
Table 12. Demographics of attendees at community meetings (excluding CIAT, ORE, and
university students who helped).
Lake Etang Lachaux Etang Douat Etang Laborde
Date 11 March 16 March 20 March
# participants 26 89* 9**
Ages 19 to 80 9 to 82 28 to 65
# > 50 years old 13 15 4
# < 20 years old 1 42 0
Communities represented
Martinere 2 1 0
Diagnostic study of three lakes in southern Haiti 39
Lake Etang Lachaux Etang Douat Etang Laborde
Lachaux 23 0 0
Levy 1 4 0
Douat 0 47 0
Sovo/Savau 0 3 0
Deglalis 0 1 0
Guichard 0 20 0
Rolin 0 8 0
Mersant 0 1 0
Kordin 0 1 0
Cliforde 0 1 0
Jouny 0 1 0
Macenot 0 1 0
Laborde 0 0 9
*About 1/2 the attendees were from a nearby school that attended the meeting.
**Raining, few people came.
All three lakes have had extreme flooding in the past 50 years, with residents describing the
floodwaters flowing into the adjacent watershed, in effect linking all the lakes. In 1986 Lachaux
flooded up to the houses closest to its south end, and flowed into the Douat watershed. Douat
residents said their lake will have water for up to 6 years at a time, claiming that 4 – 5 years ago
the lake had even more fish than Lachaux. It did have water in 2014. One man blamed erosion,
not less rain, for making the lake go dry. Laborde residents reported that in 2012 the lake
flooded up to the houses near the south end. In 2015 Laborde experience the lowest water
levels since 1975, when it was dry 4 – 5 months. It then filled after 1 night of rain and the
animals tied up in the lake bed drowned. Lachaux was also reported to be dry in 1975.
The residents of all three watersheds seem to want more trees in the watershed and desire
financial incentives to plant trees. However, they spoke of failed tree planting programs.
Douat residents said trees were cut 1985 – 1995 after which the lake went dry. Laborde
residents remember forests in the watershed until 1975- 1980, and mentioned egrets roosting
in kompesh trees. There were also many mango and abriko trees at the time. They spoke of a
program called Development Community Cretienne Haitian (DCCH) which planted both fruiting
and non-fruiting trees. In 1995/1996 people began to cut these trees. Some trees remaining
from that program (cassia, sed, mango, etc.) still exist and can be cut and sold.
All three communities seem to be aware of the impact of erosion on lake levels, and indicated
some willingness to give up land to protect against erosion. They also recognize that trees help
protect against erosion. The residents of Lachaux blame current low water levels on the new
Diagnostic study of three lakes in southern Haiti 40
National Route 7, saying that rocks from the recent construction are causing the lake to dry up.
During our survey of the watershed, we did note that the culverts that drain water from the
road are creating gullies in the hillside above the lake, and washing large rocks down to the
shore (Fig. 17 – 19).
Figure 17. Top of National Route 7 culvert above Etang Lachaux.
Diagnostic study of three lakes in southern Haiti 41
Figure 18. Bottom of culvert in Figure 9, showing erosion.
Diagnostic study of three lakes in southern Haiti 42
Figure 19. Two meter deep gully created by runoff from road culverts along hillside above
Etang Lachaux.
Springs and wells
We encountered two types of “springs” in the watersheds: true ground water springs and
shallow, hand-dug wells that expose shallow ground water (vadose water). All but one hand-
dug well at Laborde, along with a hand-pump well at Laborde, had coliform bacteria, including
E. coli. The primary source of contamination of these springs and wells are unrestricted
livestock use in or up-slope of springs. Secondary sources include human uses such as bathing
Diagnostic study of three lakes in southern Haiti 43
and washing laundry in or around these springs. Human activities, if not controlled, can
introduce soaps and detergents, as well as human transmissible diseases or infections into the
water.
Suggestions for protection are:
Limit area of activities around and up-slope of springs and wells,
Post signs with contamination advisory/safe practices for spring uses,
Avoid any construction activities in or near natural springs.
Provide work areas away from the springs for clothes washing and other activities
Watershed findings and conclusions
Soil erosion and land use
All watershed soils are basically Udepts soils which are typically nutrient poor and form a thin,
easily erodible soil profile. All lake watersheds are dominated by mountainous terrain with
extensive areas of high slope hillsides (> 40% slope), nearly all of which is under some form of
farming practices, either intercropping, cultivation or pasturing of livestock. There were very
limited areas within each watershed where structural erosion control practices such as rock
terraces and vetiver grass (Chrysopogon zizanioides) hedges have been put in place and
maintained. Agroforestry practices were evident in all watersheds and represented about 24 to
28% of the land use found in these watersheds. While such agroforestry areas sometimes show
less signs of erosion they represent less than 25% of all the land use in these watersheds while
the majority of remaining land use shows high rates of erosion and continues to contribute to
lake sedimentation and water quality degradation. It should also be noted that in most areas
where agroforestry was being practiced vegetated ground cover remains limited and soil
erosion rates remain high. Both our interviews with local residents and agricultural experts as
well as our own observations within each watershed suggest that reforestation projects have
had limited success. While the actual number of tree plantings that have been done over time
in each watershed was not available, in general most interviews indicated that the number of
trees planted was very high but few trees remain from such efforts. Those that do remain are
mostly fruit trees. No official records of the survival rates of planted trees were found but it
appears that most surviving trees that reached harvestable size were cut and used in charcoal
production within each watershed. Thus tree planting efforts appear to have had limited long-
term success and this may remain so unless watershed residences and landowners support
such planting and charcoal production is reduced or eliminated. It should be noted that
exploitation and cutting of fruit trees is more limited in these and other watersheds because of
their value as a crop for consumption and sale in the market place (personal comm., Dr. M.
Pierre, ORE, March 2015).
Diagnostic study of three lakes in southern Haiti 44
Precipitation and runoff
Several natural and human-induced factors have collectively created a prominent wet/dry
water cycle that now characterizes these lakes. First the thin Udepts soils once associated with
the historic forest have been mostly lost from hill slopes so that most rainfall now runs directly
off, causing more soil erosion with rapid infiltration of water not contributing to runoff.
Historically, vegetative cover and accumulated organic matter would have slowed and limited
runoff while also slowing infiltration rates so that subsurface water movement to the lakes
would help extend the wet periods of the lakes. Extreme losses of permanent vegetation cover
(e.g. forest), cone karst topography and a bi-model rainfall pattern now contribute to a stronger
wet/dry cycle for the lakes as well as promote more severe floods and droughts within these
watersheds and the region in general. Little can be done regarding the natural bi-model nature
of precipitation and the extreme rainfall events associated with this climate. However,
increased runoff due to bare soil conditions and severe soil erosion associated with poor
farming practices and failure to apply meaningful soil conservation measures can be reduced
and groundwater filtration increased by implementing changes in land management practices.
Lake quality and uses
This study is the first step in describing the structure and function of these depression lakes (i.e.
sinkhole lakes) with regard to their ecological services and values. Most noteworthy is the
rarity of natural freshwater lakes in the Department of the Sud or elsewhere in Haiti. This is, in
part, due to the widespread occurrence of karst geology and topography which tends to limit
the development of surface water features such as lakes and streams. This rarity and the
habitat opportunities they afford the often unique and endemic aquatic biota make them
outstanding natural resources even in their impaired condition. It is estimated that these lakes
have suffered from massive sedimentation as a result of the extensive and poor farming
practices that have developed in their watersheds over the last century or so. The extent of the
development of the alluvial fans or plains at the primary inflow areas of the lakes attest to the
nature of the erosion and sedimentation processes which are the result of human activities.
Despite the degraded nature of these ecosystems these lakes still provide many direct human
services that include livestock and human drinking water, plant foods, building resources,
fishing and fishes and grazing and cultivation areas when water levels are low. However, even
these basic human services appear in jeopardy due to increased water level fluctuations, poor
water quality and bacterial pollution. All of these services, both ecological and human, are in
jeopardy primarily due to poverty and poor land use management within each watershed.
While our studies were all done during unusually dry years with rainfalls well below the 20-year
average annual amount, much can still be said regarding creation of protected and
management areas within these watersheds to both protect and enhance these lake
ecosystems and their long-term natural and human resource values. However, because this
Diagnostic study of three lakes in southern Haiti 45
study was limited to one comprehensive sampling event and was done under less than average
water conditions, we must cannot make definitive statements regarding overall ecological
condition of these lakes. We can offer general recommendations and comments concerning
the establishment of protected areas within the watersheds (and management areas)
necessary to enhance and protect lake and watershed quality since land uses and practices are
better known and observed even within dry years. What cannot be accounted for is high water
and runoff conditions and events that are most contributing to lake sedimentation and land
erosion. It is clear that some regions within each watershed are greater contributors to soil
erosion and soil movement to these lakes but these events are better understood during major
rainfall events which never happen during our study periods.
Identification of protection and restoration zones and areas
1. Identify lake buffer zone by land use based assessments or by using identified legislative
requirements. Buffer area would be for protection and restoration activities.
One of the most commonly used approaches to the protection of aquatic resources such as
lakes, rivers and wetlands is the identification and establishment of a “buffer zone” around the
ecosystem (Richardson et.al. 2012, Klemas 2014, Sweeney and Newbold 2012). The immediate
areas around these lakes should be considered as a buffer zone (protected area) for these lakes
in which certain human activities are either controlled or eliminated to reduce shore erosion,
pollutants and habitat destruction. The buffer should encircle the lake margin and its width
determined by assessment of its potential function width or by legislation. Lacking an
assessment to determine functional protective width of a lake buffer we recommend using the
existing federal Haitian laws and regulations to protect areas found to be of value and safety for
the general community. The following are excerpts (translated by Google Translate) for Haiti
articles and regulations pertinent to protected areas around waterbodies and other sensitive
area of importance to the community:
Decree-Law of 23 June 1937 on the regulation of forests. Monitor No. 51 Thursday, June 24, 1937 DECREES Article 1. It is forbidden to do, without prior authorization, special written a qualified agent SNPA & E. R., no clearing, damage, cut, uproot or burn any tree;
a) on land with a slope equal to or greater than 30o from the horizontal;
b) around sources within a radius of 100m; c) on the banks of rivers, rivers, streams, over a 50m width on each side; d) area around lakes, ponds and natural water reservoirs, a distance of 50m.
Article 2. It is prohibited without prior authorization, special written a qualified agent SNPA & ER undertake annual crops say:
a) on land with a slope equal to or greater than 45 degrees with the horizontal; b) around the springs on a 100m rapyon; c) on the banks of rivers, streams over a 50m width on each side.
Article 3. It is prohibited unless authorized by the SNPA & ER burning savannahs, throughout the territory of the Republic, and land designated and extended to article 1 above, to "new wood" to burn the waste to crops, sarclures or other organic debris.
Diagnostic study of three lakes in southern Haiti 46
AREAS UNDER PROTECTION ZONES AND BOOKED - August 1955- Paul Magloire E Article 15. It may be designated under the name "Areas under protection" tracts of land owned or to the State or to individuals whose protection is necessary and urgent for the wellbeing of the community. Article 16. The "Areas under protection" is any area of land and use will be regulated by the Department of Agriculture, in order to combat erosion, protecting the child's Public Health to ensure sound recreation or tourism promotion. Article 17. The boundaries of these areas will be determined by the Department of Agriculture, in conjunction with the Finance and Public Works. Article 18. Are declared "Areas under protection."
1e) any area of land owned by the state or individuals over an area of at least 5 hectares, around cascades, waterfalls and around the springs supplying drinking water to urban and rural areas. 2) any amount of land owned by the state or to private or around hot sulfur springs, usually around any water tanks, over an area of at least 5 hectares. 3) any amount of land owned by the state or individuals forming the watershed sources and rivers. 4) any area of and owned by the state or individuals to be designated by the Department of Agriculture in accordance with Article 16.
Article 19. Within the limits under protection areas, areas of land will be according to the law of February 3, 1926, declared "reserved areas" and withdrawn from exploitation.
Based on our interpretation of these articles we suggest that a 50-meter buffer or 5 hectare
area (whichever is larger) be established around the most prevalent lake shoreline and used as
a protection zone and management area. Establishing exactly where the lake margin should be
in interpreting the buffer area and width is somewhat problematic since lake surfaces thus
margins expand and contract both on an annual and an inter-annual basis. One approach
would be to designate the “official” lake margin as the margin most clearly defined by the long-
term water margin and vegetation pattern observed in repeated satellite and photography
imagery, such as Google Earth imagery. Within these lake buffers better land use practices
should be required and livestock access and use controlled.
2. Identify buffers to protect springs and spring runs (i.e. spring-fed streams) within these
watershed areas.
Springs and spring runs within these watersheds need to be protected for several reasons.
Springs are a source of clean water to all of the lakes at various times of the year and probably
contribute to subsurface water flows to the lakes year round. Springs are common sources of
drinking water within all watersheds and thus need to be protected from bacteria, disease and
environmental contamination. As already noted some springs have dangerous levels of E. coli
levels that indicate users have a high risk of obtaining enteric diseases and infections. In
addition, it appears that the springs and spring runs are habitats for native fish and invertebrate
fauna that repopulate the lakes after dry periods. Therefore, springs are important in
maintaining natural and human environmental services and goods provided by the lake and
other aquatic resources within these watersheds. Typically these springs and the areas around
them are used for washing clothes and bathing, and for watering livestock and grazing. These
activities increase soil erosion and disturbances upstream and in the near vicinity of springs that
may endanger spring flows and contaminate spring water. Aquatic habitat is also degraded and
Diagnostic study of three lakes in southern Haiti 47
destroyed by intense human and livestock uses if left unsupervised. Therefore springs and
spring areas are also identified as protected areas and minimally should have buffer zones
established upstream and around them to limit and discourage livestock grazing and certain
human activities. The same buffer approach listed above for lakes can be used for springs.
3. Identify ravines and gullies that drain directly to the lake margins for protection and
management.
Eroded soils not only originate from gullies and ravines but sediment transportation is greatest
in these channels due to open channel flows and increased stream energy associated with open
channel flows. Also these channels drain directly into the lake thus increasing their potential
delivery capacity. While sheet and rill erosion are also a large problem in these watersheds,
control of these types of erosion is more difficult due to the large areas involved and thus the
need for total community involvement to achieve meaningful reductions in soil loss and
transportation. Gullies and ravines, however, are more limited in extent thus transportation of
sediments to the lakes is more easily controlled through structural erosion control measures.
4. Identify areas of mass wasting (i.e. landslides) and contain and control downslope soil loss.
Mass wasting, which is sometimes called mass movement or slope movement, is defined as the
large movement of rock, soil and debris downward due to the force of gravity. More commonly
we refer to these events as landslides. Heavy rains, widespread deforestation and high-sloped
terrain are causes of shallow landslides and high erosion rates in the mountains, which have
steep, fault-riddled topography, weak rocks, and erosion-prone soils. The combination of
deforestation and limited or poor soil conservation practices has led to numerous small
landslides within these watersheds. Slide areas are not used by the watershed communities
but can still contribute to soil loss and sedimentation. Thus these sites should be identified and
when possible steps taken to control soil loss from these discrete and easily identified sites.
5. Severely eroded, low fertility, high slope farm plots immediately adjacent to the lake basins
should be restored and protected.
Many examples of field plots showing the cumulative results of extreme soil erosion and over
farming can be found through all watersheds. These high-slope, thin soil plots are common
everywhere within these watersheds and restoring and protecting all of these farm plots would
require a massive physical and financial effort. Therefore, lake protection efforts should
initially focus only on those severely eroded field plots that drain directly to the lake margins.
These severely eroded plots are possibly of more concern to land owners and farmers which
might promote better cooperation in adopting soil conservation practices, especially practices
that may require removing some land from production. Higher potential recruitment of these
types of field plots along with the fact that they directly drain to the lake ecosystem give these
sites high protection and restoration value.
Diagnostic study of three lakes in southern Haiti 48