GEO-HYDROLOGICAL SYNOPSIS OF THE TODOS SANTOS AQUIFER

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GEO-HYDROLOGICAL SYNOPSIS

OF THE TODOS SANTOS

AQUIFER

TODOS SANTOS, MUNICIPALITY OF LA PAZ, BCS.

APPLICANT: FRBC-TODOS SANTOS DOS,

S. DE R.L. DE C.V.

JUNE, 2012


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PROMOTERS INFORMATION:

NAME: FRBC-TODOS SANTOS DOS,

S. DE R.L. DE C.V.

ADDRESS: KNOWN, TODOS SANTOS, BCS


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GEO-HYDROLOGICAL SYNOPSIS OF THE TODOS SANTOS

AQUIFER, MUNICIPALITY OF LA PAZ, BCS

CONTENTS

No. Concept Page

I. GENERAL ASPECTS ............................................................................................................... 1

I.1. Objective.................................................................................................. 1

I.2. Background.............................................................................................. 1

I.3. Location of the Todos Santos Aqui fer........................................................... 2

I.4. Access Roads and Communication Routes.................................................... 3

I.5. Weather conditions , precipitation and vegetation............................................ 4

I.5.1. Climate........................................................................................ 4

I.5.1.1. Mean annual temperature............................................................... 5

I.5.1.2. Average maximum temperature....................................................... 7

I.5.1.3. Average minimum temperature........................................................ 9

I.5.1.4. Mean annual precipitation............................................................. 11

I.5.2. Land Use and Vegetation.............................................................. 13

II. GEOLOGICAL CONDITIONS ................................................................................................. 15

II.1. Physiography.......................................................................................... 15

II.2. Hydrography........................................................................................... 17

II.3. Geomorphology....................................................................................... 20

II.4. Structural geology................................................................................... 22

III. HYDROLOGY ......................................................................................................................... 26

III.1. Uunderground hydrology (aquifier)............................................................. 26

III.2. Surface hydrology (springs)...................................................................... 31

IV. PRIOR GEO-HYDROLOGICAL STUDIES. ............................................................................. 34

No. Concept Page


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V. ANSWERS TO THE QUESTIONS FROM THE STUDY PROMOTER. ................................... 37

VI. CONCLUSIONS AND RECOMMENDATIONS ....................................................................... 44

VI.1. Conclusions............................................................................................ 44

VI.2. Recommendations................................................................................... 45VII. ANNEXES ............................................................................................................................... 46

Form #CAN-01-013, authorization for transfer of registration titles, this

document details the requirements of the 13 PAGES-procedure.

Drawing 1 of 2, includes the location of wells and springs on the INEGI

chart, scale 1:50,000.

Drawing 2 of 2, includes the location of wells and springs on Googleimages.


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I. GENERAL ASPECTS

Objective

The present study was requested by the company FRBC-TODOS SANTOS DOS,S. DE R.L. DE C.V., and its objective was to carry out an off-site study of the

Todos Santos aquifer, gathering diverse information in order to determine itspresent condition, as well as to learn the applicable regulations regarding domesticwaters, in order to support decision-making in water matters for a developmentproject intended to be carried out in the region.

The present study is based on the results of geo-hydrological studies carried out by

various government and private institutions in the present study zone and its

description will be recorded and analyzed in the present document.

BackgroundThe locality of Todos Santos, founded in 1723, is one of todays 5 municipal

departments of the municipality of La Paz, in the state of Baja California Sur,

located 80 km south of the city of La Paz, and 75 km north-northwest of Cabo San

Lucas, BCS. It is a population whose original vocation was growing sugar cane, a

crop planted by the founding Jesuit missionaries, and an activity which was carried

out over more than a century. The sugar refinery closed its operations in the 60's

due to the low selling price of the product and the introduction of new agricultural

products which allowed to harvest 2 crops per year using less water. As a result of

this success, the population began a new form of agricultural activity, mangoproduction. Nowadays, chile, tomato, and a large variety of organic products for

exportation are also seeded, and fishing and livestock activities are carried out in

the region.

Up to the late 40's, the aquifers in this entity were exploited by way of shallow

water sources (shallow waterwheels), which extracted smaller amounts of water for

domestic, farming and livestock purposes.

The current population of Todos Santos is 5,148 inhabitants: 2631 men and 2631women. It has public utilities such as electricity, and potable water, and a portion of

the locality has sewerage and drainage services.


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Location of the Todos Santos Aquifer

The geographic location of the Todos Santos aquifer, Municipality of La Paz, is in

the south-west region of the state of Baja California Sur, and is the largest urban

area of the region.

The locality of Todos Santos is the most benefited recipient of water from the

referred aquifer, located at the geographical coordinates 23 263' 55" north and

11013'24" west, latitude and longitude, respectively (Source: INEGI 2010

Population and Housing Census). (Figure 1)

LOCATION

Figure 1

Geographical LocationLatitude North: 23 26 55

Longitude West: 110 13 24

TOPOGRAPHICAL CHART, INEGI: TODOS SANTOS


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Access Roads and Communication Routes

The Transpeninsular Highway (Federal Highway No. 1) provides land

transportation in the south of this Entity, specifically at highway section 112+00 km

of La Paz-Cabo San Lucas (short route), where a beltway is under construction in

the east zone of the Todos Santos locality, BCS. By air, there is access through

the General International Airport Manuel Mrquez de Len, in La Paz, and Los

Cabos International Airport, located at San Jos del Cabo, BCS. Marine service is

provided in two ports: La Paz and Cabo San Lucas. (Figure 2).

COMMUNICATION ROUTES

Figure 2


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WEATHER CONDITIONS, PRECIPITATION AND VEGETATION.

Climate.

The Tropic of Cancer crosses this locality, generating a temperate climate. It is

known as The Never-Ending Spring City of the State, and its climate can be 5 to

8C lower in relation to the rest of the State, which favors the growth of palm

groves, large fruit trees which give the region a resemblance of an oasis.

The mean annual temperature is 21.3C (table 1, chart 1.a, and 1.b); the maximum

temperature is 27.3C, occurring in the month of September (table 2, chart 2.a, and

2.b); and the minimum temperature is 15.4C, occurring in the month of March

(table 3, chart 3.a, and 3.b). The mean annual precipitation is 150.2 mm, being

September the month with the highest average rainfall.

(Table 4, chart 4.a, and 4.b). (Source: National Water Commission). (Figure 3).

Figure 3

MEAN ANNUAL PRECIPITATION


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Mean annual temperature.

The mean annual temperature is 21.3C, being the year 2007 the one with the

lowest average annual temperature (18.4C), and the year 1964 the one with the

highest average annual temperature (23.3C), with a falling temperature tendency.

Mean Annual Temperature RecordsYear Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Annual

Total: 1045.1Average: 21.3

S/D = No data

Table 1


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Chart 1

MEAN ANNUAL TEMPERATURE


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Average maximum temperature

The average maximum temperature is 27.3C, being the year 2002 the one with

the lowest average maximum temperature (25.4C), and the year 2009 the one

with the highest average maximum temperature (30.1C), with an increasing

temperature tendency.

Average Maximum Temperature RecordsYear Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Annual

Total: 1336.6Average: 27.3S/D = No data

Table 2


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Chart 2.a

AVERAGE ANNUAL MAXIMUM TEMPERATURE


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Average minimum temperature

The average minimum temperature is 15.4C, being the year 2007 the one with the

lowest average minimum temperature (10.8C), and the years 1964 and 1997 the

ones with the highest average minimum temperature (18.1C).

Average Minimum Temperature RecordsYear Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Annual


S/D = No data

Table 3


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Chart 3.a

AVERAGE ANNUAL MINIMUM TEMPERATURE


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Mean annual precipi tation

The average minimum precipitation is 150.20 mm, being the year 1995 the one

with the lowest mean annual rainfall (8.5 mm); however, it is important to mention

that in the months with most rainfall, CONAGUA did not obtained any records

(August, September, October, and November); and being the year 1989 the one

with the highest mean annual precipitation (404.7 mm).

Mean annual precipitation recordsYear Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Annual


S/D = No data

Table 4


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Chart 4.a

ANNUAL PRECIPITATION


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Land Use and Vegetation.

The diversity of land use is classified as irrigation agriculture, cultivated grasslands,

and crassicaulous and sarcocaulous shrubs. (Figure 4)

LAND USE

Figure 4

The vegetation cover is a factor considered in the evaluation of runoff units; the

density and type of cover intervene in the amount of runoff, acting as a retardant,

and promoting infiltration.

In order to determine the type of vegetation in the basin, a topographic land use

and vegetation map from the INEGI was used (F12-2-3-5-6). (Figure 5)

LAND USE AND VEGETATION


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Figure 5

(S) SARCOCAULOUS-SEMI-THORNY SHRUBS.These zones show great activity

of Opuntia cholla (Cholla), which is favored by the livestock activities in the area.

In some regions, the goat livestock is Nubian breed; and Ruellia californica (Rama

Parda) is generally observed as one of the species that is most foraged by this

type of livestock. Lysiloma candida (Palo blanco) is more abundant in brooks.

(S) SARCOCAULOUS-THORNY SHRUBS. These communities are found over

the alluvial fans, foothills and low hills, and generally develop on stony substrata.

The physiognomy of these communities is provided by Pachycereus pringlei

(Cactus), Machaerocereus gummosus (Sour Pitaya), and Lophocereus schottii

(Garambullo), which form small colonies. Some plants such as Salicornia sp.,

Lycium sp., Atriplex sp., and Maytenus phyllanthoides are abundant in locationsnear the coast.

GROUND LEVEL.RAS. Annual and semi-permanent irrigation crops.

Cultivated grasslands, cattle.

La Reforma brookbasin

LAND USE AND VEGETATION CHART, INEGI: SAN JOS DEL CABO (F12-2-35-6)


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II. GEOLOGICAL CONDITIONS

Physiography

The area under study originates in a mountain system, and follows a south-west

direction, so runoffs begin in a mountain of medium elevation, and the discharges

flow into the Pacific Ocean, with elevations which do not exceed 320 meters abovesea level (m.a.s.l.).

The study zone belongs to the southern part of the Magdalena plains discontinuity,

located in the central western portion of the State, bordered to the north and east

by the sub-province Sierra de la Giganta (a mountain range), to the west and south

by the Pacific Ocean, and to the south-east by the Del Cabo discontinuity. (Figure

6 and 7).

PHYSIOGRAPHY

Figure 6

SUB-PROVINCEPHYSIOGRAPHY


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PHYSIOGRAPHY

Figure 7

Physiographically, the zone has a structure in the shape of a depression, with the

above mentioned borders.


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Hydrography

The States setting within the hydrological division of the Mexican Republic guides

us to the region to which our area under study corresponds; and in order to study

each region in the most detail, we need to resort to a different source of

information, i.e., that of the basin, whose analysis may afford a greater hydrological

description of the environment.

The entity is situated among the following hydrological regions:

RH 2 Central Baja California West (Vizcano)

RH 3 South Baja Cali fornia West (Magdalena)

RH 5 Central Baja California East (Santa Rosala)

RH 6 South Baja California East (La Paz)

These are further divided into basins and sub-basins.


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Region Basin Sub-basin

South-west BajaCalifornia

(Magdalena)

28,470.42 Km2

3A

"Caracol Brook-CandelariaBrook"

8,003.26 km2

Candelaria Brook 507.23 km2

San Jacinto River 226.00 km2

Santa Ins 681.00 km2

El Carrizal Brook 2,090.21 km2

Datilar Brook 1,433.31 km2

Guadalupe Brook 644.84 km2

Caracol Brook 2,420.67 km2

Salado Brook 2,240.87 km2

3B

"Venancio Brook-Salado Brook"

15,479.19 km2

Magdalena Bay 3,616.93 km2

Soledad Brook 4,597.26 km2

Santa Cruz Brook 2,054.05 km2

Santo Domingo Brook 1632.19 km2Venancio Brook 1,337.89 km2

3C

"Mezquital Brook-ComondBrook"

4,987.97 km2

Comond Brook 1,004.42 km2

Pabelln Brook 770.39 km2

Cadegomo River 1,831.07 km

2

Mezquital Brook 533.35 km2

These regions are part of the Pacific Ocean slope.

The area under study is located within hydrological region No. 3, South-West Baja

California (Magdalena), basin 3A "Caracol Brook-Candelaria Brook", with a surface

area of 8,003.26 km2, and the sub-basins which are part of it are the following:

Candelaria Brook 507.23 km2, San Jacinto River 226.00 km2, Santa Ins 681.00

km2, El Carrizal Brook 2,090.21 Km2, Datilar Brook 1,433.31 km2, Guadalupe

Brook 644.84 km2, Caracol Brook 2,420.67 km2. The population settlements

located within these areas are the following: Guadalupe, El Conejo, La Aguja, San


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Isidro, Todos Santo, San Pedro, El Triunfo, El Carrizal, Plutarco Elas Calles, and

Migrio. (Figure 8)

HYDROGRAPHY

Figure 8

Study zone


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Geomorphology

Although geological and geomorphological evidences are not very clear, it is

possible that the La Reforma brook is in fact a geological fault connected to the

discontinuous fault of La Paz; and if so, we would be speaking of one of the largest

geological structures.

The presence of geological structures such as these and the intense fracturing

factor create porosity and secondary permeability of the rock, which favor, above

all, the increase of underground water flow through said rocks.

The valley in Todos Santos is narrow: 2.5 km in width at the sea mouth, and up to

2 km inland, where it narrows to 1.3 km in width by 3 km in length. In this zone,

which corresponds to the main zone of the Todos Santos valley, land rises fromthe coastline up to 160 m.a.s.l. to the exploitation height TS23. On the highest part,

the valley opens out and is known as the Plan de San Juan, with an extension of 5

7 km, and a moderate slope of 160 to 260 m.a.s.l. There is another small coastal

valley to the south of Todos Santos, which opens out into the ocean at about 800

meters. The main surface current corresponds to the La Reforma Brook, which

originates at the Santa Ins dam, and runs along the narrow valley of Todos

Santos to flow into the ocean. The valley is surrounded by topographic elevations

made up essentially of metamorphic and intrusive igneous rocks, and a lower

degree of conglomerates. They have various geographic forms, partly rounded,with a soft slope, and partly dissected by numerous streams and brooks. They go

as high up as 300 m.a.s.l. Figure 9 shows aspects of this valleys landscape.


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GEOMORPHOLOGY OF THE AQUIFER

Figure 9


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Structural geology

The study zone is made up of sedimentary materials of alluvial origin (alluvium);

these coarse, medium and fine sandy materials are produced by rock erosion and

transported there through surface water runoffs. Its physical properties, such as

porosity, transmissivity and degree of compaction suggest high permeability and

hydraulic conductivity values.

A unit of these rocks is sedimentary, and outcrops on the right side of the brook,

where metamorphic rocks of shale, gneiss and metasedimentary type are also

found. The most abundant are shales, characterized by the appearance of several

flattened laminates. Generally, these rocks present an intense fracturing pattern,

and even mineralogical re-crystallization is observed in some regions.

On the east side of the brook, these rocks are observed in the form of cliffs which

are locally humid and have presence of water.

The geological units which constitute the study area are presented in the

Geological Chart, Scale 1:250,000 San Jose del Cabo F12-2-3-5-6. (Figure 10).


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Figure 10. Geological Units

Q (al) ALLUVIAL. They belong to the 5% of the total basin area, are formed byalluvial deposits composed of gravels, pebbles, sands, and, to a lesser degree,

clay soils, cumulated along the valleys and riverbeds. The type of components

varies widely according to the composition of the source, and also presents

variations in granulometry, depending on the topography of the land. They are

found in the form of alluvial fans, and sometimes as alluvial terraces. They can

originate from intrusive igneous and metamorphic rocks, sometimes included in a

thick sandy matrix. These deposits are highly permeable; the proof of this are the

human settlements located on the shores of the brook.

Q (cg) CONGLOMERATE. It is located in the largest portion of the basin under

study, comprising 70% of the basin, with conglomerates which form alluvial fans on

the borders of the La Victoria mountain range; they are colored gray to dark gray

with green tones, with a 10 to 20 m thick, and arranged in the form of plateaus

inclined towards the center with a graben structure. The size of the clasts is highly

variable, as near the water source is possible to find conglomerates of 1 m in

La Reforma brook

basin

GEOLOGICAL CHART INEGI: SAN JOS DEL CABO (F12-2-3-5-6)


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diameter or larger; but no so in the lower parts and away from the mountain range,

where they vary from 5 cm to 20 cm in diameter. Sandy soils of varying dimensions

are sporadically found, which get buried and lost. These deposits present little

compacting and are considered to have a medium to high permeability, and

concordantly overlie the Salada Formation.

M (Metasedimentary). A sedimentary sequence with regional metamorphism,

including shales and phyllites, which in contact with transcurrent failures present

different types and degrees of cataclasis, such as boudinage structures. Although

all exposed metamorphic rocks in the chart are affected by intrusive acid agents,

the metasedimentary rocks are least damaged by this phenomenon. They have a

high abundance of quartz, muscovite, andalusite, and to a lesser degree, biotite; its

textures vary from porphydoblastic to lepidoblastic, and their metamorphism is low

grade and political class. It outcrops to the north of Todos Santos, and on the westside of the La Victoria mountain range; it is gray with brown tones. This unit

outcrops on the far western side of the diorite-tonalite grained plutonic massif. It

corresponds to 8% of the total area of the study basin.

M(Gn) GNEISS. Highly weathered orthogneiss rock which contains a

holocrystalline monzonite porphyry dike with hydrothermal alterations, as can be

seen by the presence of epidote, chlorite and sedicite. It belongs to the feldspathic

quartz class, and has a gray color that adopts deep red tones with weathering.

To the south-west of Todos Santos outcrops a white colored gneiss with graybands, which appears to originate from intermediate intrusive rocks. Its mineralogy

is quartz, plagioclases and bands of mica and hornblende dark minerals,

occasionally surfacing from muscovite shales of gray color and red tones. It is

found in only a minimum portion of the total area of the study basin.

M(c.met) METAMORPHIC COMPLEX. This unit covers only 6.5% of the total

basin area, and includes mainly three types of rock: basic class shale, feldspathic

quartz class gneiss and migmatite. The outcrops of these rocks are located to the

south and south-west of the locality of Todos Santos.

Shales are black with green tones, sometimes with alternating bands of muscovite

shales; its structure is schistose with lepidoblastic and porphyroblastic textures with

minerals from plagioclase, quartz, hornblende, tremolite-actinolite, traces of biotite


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and chlorite, epidote and sphene, which were classified as belonging to the green

shale facies, amphibolite subfacies, basic or intermediate class.

The gneisses are white colored with black bands. They present bands of quartz

and mica with amphibolites; they have prints of cataclastic metamorphism and are

affected by intrusive bodies, and as a whole, they have monozonite porphyry dikeswith a green coloring with black tones.

Migmatites are present with a mix of dark amphibolite rocks and white granite

rocks. The first correspond to the preexisting rock, i.e., the metabasic rock, and the

second, to the material which originated in situ.

Tpl(ar-cg) SANDSTONE-CONGLOMERATE. It comprises 5% of the total basin

area and is located on the west side. It is formed by intercalated polymictic

conglomerates with a sandy matrix with calcareous cement and sandy stratum,

some of which are conglomeratic and others have crossed stratification. Stratumvaries from 0.80 to 1.00 m in thickness, and its clastics are from volcanic rock,

mainly siliceous pyroclastic rocks which vary from sub-round to well round. The

unit presents differential weathering and is considered a zone with medium to high

permeability.


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III. HYDROLOGY

UNDERGROUND HYDROLOGY (AQUIFER)

The official denomination of the Todos Santos aquifer was published in the Official

Gazette of the Federation, dated December 5th, 2011, which states the following:

OFFICIAL GAZETTE OF THE FEDERATION

SECOND SECTION

MINISTRY OF THE ENVIRONMENT AND NATURAL RESOURCES

AGREEMENT by way of which the unique denomination of the aquifers recognized

in territory of the United Mexican States is established and informed to the general

public, by the National Water Commission (Comisin Nacional del Agua, CNA), as

well as the standardization of aquifer names used for the issuance of concessions

or assignment titles, or permits granted by this decentralized body.

STATE KEY UNIQUE DENOMINATION KNOWN ASBAJA CALIFORNIA SUR 313 TODOS SANTOS TODOS SANTOS BCS13

The Todos Santos aquifer has a territorial extension of 164.7 km2. Its geographical

limitations were published in the Official Gazette of the Federation, dated August

28th, 2009 (second section), which states the following:


SECOND SECTION


AGREEMENT by way of which the geographical location of 371 aquifers in

domestic territory is provided, the mean annual availability of underground water of

282 aquifers is updated, and, for improved precision, the geographical description

of 202 aquifers is modified.

XLV.- HYDROLOGICAL REGION - ADMINISTRATIVE I "PENINSULA OF BAJA

CALIFORNIA" AQUIFER 0313 TODOS SANTOS


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APEXWEST LONGITUDE NORTH LATITUDE

DEGREES MINUTES SECONDS DEGREES MINUTES SECONDS

1 110 12 35.6 23 22 52.3

2 110 15 16.2 23 27 34.0

3 110 13 19.3 23 28 28.9

4 110 12 21.3 23 30 0.85 110 12 26.4 23 30 43.0

6 110 10 37.1 23 32 7.7

7 110 9 14.1 23 32 21.9

8 110 8 5.2 23 32 18.0

9 110 4 13.4 23 30 57.3

10 110 3 8.9 23 31 30.9

11 110 1 55.7 23 32 42.7

12 110 0 21.5 23 32 15.6

13 110 4 5.4 23 29 46.3

14 110 6 19.4 23 25 38.215 110 11 3.8 23 24 37.1

1 110 12 35.6 23 22 52.3

The main sources for the aquifer replenishment are the General Agustn Olachea

Avils Dam, direct filtration from rainwater on the valley, and infiltration of surface

water runoff into the intermittent streams. During the rain, infiltration is more

noticeable at foothills of high topographic elevations. It is important to mention that

rainfall is scarce; however, there are occasionally cyclone events with abundant

rainfall, which result in rapid aquifer recovery.

The underground water discharge is carried out by way of extraction through wells

and waterwheels, as well as by underground outlets which discharge into the

ocean, and are presently found in a dynamic balance which controls the saltwater

intrusion in the coastal region, avoiding the occurrence of saltwater invasion into

the valleys.


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Figure 11 shows the limitations of the Todos Santos aquifer.

GEOGRAPHICAL DELIMITATION OF THE TODOS SANTOS AQUIFER

Figure 11

Geographical LocationLatitude North: 23 26 55

Longitude West: 110 13 24

TOPOGRAPHICAL CHART, INEGI: TODOS SANTOS (F12B33) Y EL ROSARIO (F12B23)


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Figure 12 shows the operation of the aquifer in the Todos Santos valley, which

includes the permeable granular materials limited by the impermeable rocks, in the

central and narrow part of the valley. It can also be observed the saturated zone

which forms the aquifer, and the water surfacing in springs over the margins of the

Reforma Brook, which originates the surface runoff. It also shows the dischargeform of underground water, as well as the direction of the underground flow.

Figure 12. Illustrative sketch of the functioning mode of the Todos Santos aquifer.

Photographs: Left, view of the population settlement and the valley of Todos

Santos. Right, lagoon formed before the mouth of the Reforma Brook into the

ocean.


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The availability of the Todos Santos Aqui fer is negative, it has a deficit (over-

exploitation) of 151,000 m3; this information was published in the Official Gazette

of the Federation dated July 8th, 2010, which states the following:



AGREEMENT by way of which the results of the studies of the mean annual

underground water availability are informed for 44 aquifers in the United Mexican

States, which are part of the indicated hydrological regions:

HYDROLOGICAL-ADMINISTRATIVE REGION I PENINSULA OF BAJA CALIFORNIA

KEY AQUIFER R DNCOM VCAS VEXTET DAS DEFICITVALUES IN ANNUAL MILLION CUBIC METERS

STATE OF BAJA CALIFORNIA SUR

0313 TODOS SANTOS 18.4 14.7 3.851039 16.3 0.000000 -0.151039

Where: R: mean annual replenishment; DNCOM: compromised natural discharge;

VCAS: concessional volume of underground water; VEXTET: extraction volume of

underground water consigned to technical studies; DAS: mean annual availability

of underground water.

Based on the above, the regulatory and administrative authority for the vital fluid(the National Water Commission) does not grant new concessions by direct

assignment. The only option for having aquifer water for any activity is the

acquisition of user titles which have a valid concession title; another option is by

way of the perforation of brackish wells located on coastal zones, or even direct

seawater intakes for desalination process.


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SURFACE HYDROLOGY (SPRINGS)

In the case of surface water (springs), the study zone is classified as having a

DEFICIT, without the legal possibility of granting concessions by direct

assignment, and as opposed to underground water, the only option here for

obtaining any volume of surface water for any activity is to acquire the user titles,

which include a valid concession title.

It is important to mention the mean annual availability of surface water published in

the Official Gazette of the Federation dated November 1st,2011, which states the

following:



AGREEMENT by way of which the mean annual availability of surface water is

updated for the water basins of La Pursima, Mezquital Seco, Santo Domingo,

Bramonas, Santa Rita, Las Pocitas-San Hilario, Conejos-Los Viejos, Melitn

Albaez, La Matanza, Caada Honda, Todos Santos, Pescaderos, Plutarco E.

Calles, Migrio, and El Carrizal, which are part of the Hydrological Region number

3, South-West Baja California.

TODOS SANTOS HYDROLOGICAL BASIN: AVAILABLE VOLUME AT THE

OUTLET, 0.00 MILLION CUBIC METERS. CLASSIFICATION: (DEFICIT).

The available volume indicated in the above paragraph includes the source of the

El Salado Brook, up to its mouth into the Pacific Ocean.

The Todos Santos water basin has a surface water source of 164.7 square

kilometers and is limited to the north by the La Matanza and Caada Honda water

basins, to the east by the Pescaderos water basin, to the south by the Pescaderos

water basin, and to the west by the Caada Honda water basin.

The Todos Santos aquifer has 3 springs, denominated San Juan (23 28' 41.65''

latitude north and 110 12' 36.79" longitude west); San Regis (23 27' 37.84'' N

latitude north and 110 13' 25.16" longitude west); and El Salado (23 26' 11.75''

latitude north and 110 10' 17.35" longitude west).


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Following is the throughflow table performed by CONAGUA in 2007 (date

unknown), and those carried out recently on the Jurez Dam canal:

DATE OBTAINED THROUGHFLOW RESULT(LTS/SEC)

2007 195

JUNE 1, 2012 (14:00 HRS) 110

JUNE 6, 2012 (19:00 HRS) 140

The La Reforma Brook is the main runoff with incidence in the study area, it has a

67.097 km2 basin; its main riverbed is 18,159.88 m long, the streams

concentration time is 135 minutes (2.26 hrs), the riverbed slope is 1.71%. A

hydrological study was carried out to determine the design flow for return periodsof 10 and 1000 years, obtaining the following results: 10 years showed a flow of

170.32 m3/sec., with a maximum precipitation of 170.32 mm; the 1000 year return

period presented a maximum design flow of 756.65 m3/sec., with a maximum

rainfall of 369.01 mm.

The geographical coordinates of the throughflow point on the Juarez dam canal

are: 23 27' 13.2" latitude north and 110 13' 29.5" longitude west (figure 13).


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THROUGHFLOW POINT

Figure 13

Geographical LocationLatitude North: 23 17 13.2

Longitude West: 110 13 29.5


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IV. PRIOR GEO-HYDROLOGICAL STUDIES.

The following is a description of the summary of found GEO-HYDROLOGICAL

studies.

a) GEO-HYDROLOGICAL STUDY OF TODOS SANTOS VALLEY,

TERRITORY OF BAJA CALIFORNIA (SOUTH-WEST VALLEYS),

prepared by Tcnicas Modernas de Ingeniera, S.A. for the SRH, in the year

1974.

It corresponds to the geo-hydrological study of information gathered from the study

zone. Its objective was to recognize the hydraulic operation of the aquifers and to

quantify them in order to determine the exploitation and replenishment conditions

which may serve as a base for the establishment of appropriate policies for the

exploitation of its resources.

Regarding the valley of Todos Santos, it was calculated that there was a stored

volume of 33 Mm3, an extraction of 1.0 Mm3/year carried out by way of 9

waterwheels and 15 wells. Replenishment was calculated at 0.5 Mm3/year. It was

cataloged as over-exploited at 0.5 Mm3/year.

b) THE GEO-HYDROLOGICAL STUDY OF THE BASIN OF "VALLEYS OF

THE SOUTH-WEST" IN THE STATE OF BAJA CALIFORNIA,prepared by

Acuaplan, S.A. for the SARH, in the year 1981.

The objective of the work was to define the prevailing conditions at that time in the

aquifers in the south-west valleys of BCS, to quantify them and to define the

salinity of the underground water.

It indicated that at that time the extraction water flow of Todos Santos was

estimated at 2.377 Mm3/year, with a replenishment of 6.1 Mm3/year, and it was

considered to be practically in balance.

c) CHARACTERIZATION OF WATER USERS, TODOS SANTOS AND EL

PESCADERO BASINS, MUNICIPALITY OF LA PAZ, BCS, prepared by the

Rural Program and Social Participation Unit of the National Water

Commission at the Baja California Sur State Management, in the year 2000.


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This document includes data on the characterization of underground

water users in the El Pescadero and Todos Santos valleys.

For the Valley of Todos Santos, the data in this work indicates that

Acuaplan estimated the replenishment at 3.8 Mm

3

/year, and thatthere were 46 water collection points and that the concessional

volume was 3.034 Mm3/year. The mean annual precipitation used

was 271 mm; the extraction was 1.6 Mm3/year up to the year 1991,

and 3.0 Mm3/year from the year 1992 to 1999. It mentions the 3

existing springs with a volume of 584 to 600 Mm3/year, and with a

recorded abatement of 1.22 meters.

d) HYDROMETRIC DATA OBTAINED BY THE CNA. The information

provided by the Underground Water offices of the CNA at BCS shows thethroughflow data of the year 2007, at the following locations of the Todos

Santos aquifer:

Jurez Dam canal: Q = 195 Ips

e) Study carried out to determine the feasibility of underground brackish

water extraction for desalination at the following aquifers: Migrio,

Plutarco Elas Calles, El Pescadero, Todos Santos, and Caada Honda,

B. C. S.", prepared for the Local Direction of CONAGUA by the companyLESSER Y ASOCIADOS, SA DE CV, in December 2007, which states the

following in chapter 10:

CHAPTER 10.- AVAILABILITY IN ACCORDANCE WITH NOM-011

The mean annual availability of underground water was determined

by applying the specifications and method indicated by the Official

Mexican Standard NOM-011-CNA-2000, denominated Conservation

of the water resource, which establishes the specifications andmethod for determining the mean annual availability of domestic

waters, in its relative fraction of underground waters.


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In accordance with said standard, the mean annual availability is

obtained by the total replenishment minus the natural compromised

discharge and the concessional water volume inscribed in the Public

Registry of Water Titles (Registro Pblico de Derechos de Agua,

REPDA).

Todos Santos.

For this aquifer, the mean annual replenishment at the balance zone

is 17.09 Mm3/year. A natural compromised discharge was

considered, which corresponds to the underground outlet to the sea,

and rises up to 1.15 Mm3/year, plus the spring water, which

corresponds to 12.56 Mm3/year. On the other hand, the concessional

underground water volume inscribed in the REPDA was 3,851,039

m3

/year on October 31st

, 2007, in accordance with the publication inthe Official Gazette of the Federation. Therefore, the mean annual

availability of underground water is as follows:

Mean annual

availabili ty of

underground

water m3

=

Mean annual

replenishment -

Compromised

discharge -

Concessional

volume

508,961 = 18,070,000 - 13,710,000 - 3,851,039

The exploitation of the spring water which is discharged into the sea

(300 Ips) is recommended, as that spring water is presently

unexploited, and corresponds to the surface runoff water. There is

apparently no availability; however, the extraction of underground

water is lower than the concessional amount, which currently

translates into a positive storage change.


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V. ANSWERS TO THE QUESTIONS FROM THE STUDY

PROMOTER.

How has the aquifer changed during the last 50 years?

Based on the historical information of the Todos Santos aquifer, the

underground waters (wells) have not suffered substantial changes, and

present a deficit of 151,000 m3, which represents 0.83% with respect to

the mean annual replenishment. The extraction depths remain at the

standard of 10 to 30 m depth.

Regarding surface waters, if we compare the date from the throughflow

calculated by CONAGUA, at present, the San Regis spring does not drain,

and the canal at the highway crossing does not drain either, and the

present throughflow carried out at the Jurez dam has a flow of 140 lps,

which is 55 lps lower; however, here we must cons ider some variables

which might have incidence, such as the time of year and season of the

throughflow carried out by CONAGUA. Despite the above, we may

DEDUCE that there is a reduction in the discharge water flow of the

surface water.

Moreover, if we take the flow of 140 Ips as a constant surface water

discharge flow, we can extract an annual volume of 4'415,040 m

3

, which isthe current concessional volume for CONAGUA; and what is even more

favorable is that based on the decree dated November 1st, 2011,

CONAGUA must not grant more concessions, and only transmission to

users with a valid concession t itle may be author ized.

Are there multiple aquifers in the Todos Santos area?

NO, there is only one aquifer.

Generally, how much water is there in the aquifer?

It is important to highlight that the present document is based on the off-

site information and 2 on-site throughflows which were carried out in

order to estimate the volume present at the spring, which data was

included in the body of the present document. In order to determine the


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availability of the underground water, it is necessary to carry out various

studies (geophysical, well throughflows, etc.), which provide real and

current information on the zone. Moreover, if we consider the throughf low

carried out, as well as the publications cited from the Official Gazette of

the Federation, it is established that the aquifer has a minimum annualavailabili ty of 22 mil lion m

3

How are aquifers replenished?

The replenishment or recharging of the Todos Santos aquifer is by direct

infiltration of rainwater on the valley, as well as the infiltration of surface

water runoff into intermittent streams; an important replenishment source

is the Santa Ins Dam.

If the present draught continues, how long will the water supply last?

If we consider that the study expresses that the aquifers s tored volume is

33 million m3, with a simple arithmetic operation we could calculate that

there is suff icient water to last 10 more years.

What occurred in the 50s which made the aquifer change, and caused theclosure of the sugar cane refineries in Todos Santos?

The main problem presented was the low selling price of the product, as

well as the introduction of other agricultural products which allowed

harvesting 2 crops per year using less water. Independently of the above,

sugar cane was a product which used a lot of water for its development

and production.

Detail of the water acquisition restrictions.

Article 27 of the Pol it ical Const itut ion of the United Mexican Statesestablishes that the property of land and water included within the limits of

domestic territory correspond originally to the Nation.

and any Mexican, company or trust which is legally incorporated may

carry out the acquisition of water volumes; it is impor tant to mention that

concessions are not granted to foreigners.


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Does the Domestic Waters Law limit the extraction of surface and undergroundwater?

YES, THERE ARE RESTRICTIONS. The main restriction at the Todos

Santos aquifer is that there is no availability of the underground and

surface water. The only option there is in order to obtain water volumes is

the acquisition of titles by way of water transmission from users with

valid concession titles. ATTENTION: despite the option of acquisition of

water volumes from third parties, CARE MUST BE TAKEN BEFORE

NEGOTIATING SUCH VOLUMES, as the legal status of the title must be

verified (to make sure it is valid), the location of the providing well and

acquiring well of the title must be verified, the distance between the

closest well to the point where the new well will be constructed, because

CONAGUA has the criteria of there not being any well within 1,000 m ofthe new one.

Is it possible to acquire a water title and leave it at its present location until afinal location is defined for the extraction well?

In order to apply for a title transfer in CONAGUA, if you w ish to leave the

well at the current location, you must validate the property where the well

is located; and in this case, the land where the well will be located must

be purchased, or you must have a lease contract with the current owner,in order to transfer the well to the permanent location later; if these

documents are not available, the transfer wil l not be authorized. It can be

requested to CONAGUA (with pr ior authorization) to save the volumes for

future use; a term of 60 days will be granted to define the location of the

new water source, as well as the exploitation initiation date.

When a water title is acquired, is it necessary to demonstrate the extractionmethod and the location where the water will be used, and to have a permit to

do so before CONAGUA grants a title in your name?

When a file for a title transfer is incorporated, the characteristics of the

new well must be stated (perforation depth, perforation diameter, casings

and discharge), such as if an electric or combustion motor will be used,

the type of pump to be used (vertical, submergible), the purpose for which

the water will be used, the map or plan of new works to be carried out,


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etc. (Annexed form #CAN-01-013, authorization for transfer of registration

titles, this document details the requirements of the 13 PAGES-

procedure).

Is it possible to extract water from the Todos Santos aquifer in order to transferit through a pipeline to Pescadero?

NO, IT IS NOT POSSIBLE FOR INDIVIDUALS, as that is only carried out

when required for human consumption, and it is by volume assignments

of the municipal or state government.

How is it possible to obtain a CONAGUA report of the granted water titles?The following is a list of the presently granted titles.


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UNDERGROUND WATER CONCESSIONS (WELLS)

No. TITLE NO. TITLE HOLDER WELL VOL.

1 01BCS101733/03APOC08 JESS VALADEZ AMADOR 43,000

2 01BCS101745/03APOC08 ALFONSO GULUARTE SALGADO 85,000

3 01BCS101759/03IPDL08 HERIBERTO PARRA HAKE 20,000

4 01BCS101771/03AMDL08 MINISTRY OF AGRICULTURE, LIVESTOCK, RURALDEVELOPMENT, FISHING AND AUGMENTATION 100,000

5 01BCS102104/03GPDL09 AMADA CASTRO VDA. DE MARTNEZ 1,500

6 01BCS102408/03APGR97 MARA GUADALUPE CASTAEDA PELATOS 21,000

7 01BCS104291/03APDL09 KAREN RODRGUEZ BREMEN 36,800

8 01BCS104892/03ILGE02 E DEMETRIO VICTORINO SALGADO VILLALOBOS 3,000

9 01BCS105487/03CPDL09 WENCESLAO, JACINTO AND CLEMENTEGARRIDO GONZLEZ 2,000

10 A1BCS100192/03GMGR95 RAL SALGADO BELTRN 3,000

11 A1BCS100511/03HSGR95 POTABLE WATER SYSTEM AND MUNICIPALDRAINAGE OF THE LA PAZ MUNICIPALITY 1,010,000

12POTABLE WATER SYSTEM AND MUNICIPALDRAINAGE OF THE LA PAZ MUNICIPALITY 4,000

13 A1BCS101059/03IPGE95 CARLOS ARNAUT OJEDA 3,000

14 A1BCS101349/03GPGE96 DHELMA BELN AND MARICELA SANTA ANAOSUNA 3,000

15 A1BCS101516/03IPGR96 HAPPY, OSCAR AND JOHN MORENO RUTOWSKI 20,000

16 A1BCS101517/03 APGR96RODOLFO, MANUEL, YOLANDA, VALENTE,TERESA, ROSA, BLANCA, FRANCISCO JAVIERAND MARTIN SALGADO VILLALOBOS

32,000

17 01BCS104753/03APDL09 MIGUEL LOGAN CARRASCO 30,000

18 01BCS105122/031 MGE06 BANCO INVEX, S.A. INSTITUCIN DE BANCAMLTIPLE, INVEX GRUPO FINANCIERO 1,000,000

19 01BCS101780/03APDL10 SUSANA MICAELA MAHIEUX DUBOT 51,100

20 1BCS102195/03CPGE97 BANCO INTERNACIONAL, S.A. 3,000

21

01BCS101514/03ISGR03

TODOS SANTOS COOPERATIVE 50,000

22 TODOS SANTOS COOPERATIVE (MALDEORIN) 300,00023 TODOS SANTOS COOPERATIVE (LA PRADERA II) 240,000

24 TODOS SANTOS COOPERATIVE (LAS PRADERAS) 196,000

25 TODOS SANTOS COOPERATIVE (SAN JUAN) 25,000

26 TODOS SANTOS COOPERATIVE (TEZCALAMA) 350,000

27 TODOS SANTOS COOPERATIVE 70,000


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28 A1BCS101397/03IPGE96 TODOS SANTOS COOPERATIVE 3,000

29 1BCS102088/03GPGE96 LEN VALADEZ AMADOR 1,500

30 01BCS104292/03SPGE99 MARTHA OLIVIA SALGADO GUERRERO 4,750

3,711,650

SURFACE WATER CONCESSIONS (SPRING WATER)


A 01BCS103261/03AHDL09 ASSOCIATION OF USERS OF THE IRRIGATIONUNIT OF TODOS SANTOS COOPERATIVE 570,000

B 01BCS105057/03ABDL09 TODOS SANTOS COOPERATIVE 2,360,000

C 01BCS105305/03AODL07 TODOS SANTOS COOPERATIVE 1,445,400TOTAL CONCESSIONAL VOLUME: 4375,400

Is it possible to obtain information about the rainfall in the Todos Santos area inthe past 75 years?

CONAGUA has records only since the year 1961, which are included in

page 11 of the present document.

May we ask you to have a look at the concrete infrastructure that was recentlybuilt, north of the town, to see if it may have an impact on the surface water?

If this refers to piles (bridge support structures) intended for the

construction of the beltway, I will mention that there is no impact on the

surface water, as the San Regis Spring presents free runoff, which comes

from the mountain s lope.


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OUTLET WORKS TO THE NORTH

Photographs: Piles for bridge construction

Is it recommendable to perform any type of maintenance for the area (cleaningor dredging) in order to obtain water from the dam?

The dredging recommendation would be exclusively for the areas which

do not have vegetation (do not deforest the area), in order to avoid a high

percentage of evaporation generated by contact with solar light and high

temperatures.


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VI. CONCLUSIONS AND RECOMMENDATIONS

Conclusions.

At present the aquifer is in relative balance, regarding both underground andsurface water.

Generally, the depth at water level has been maintained without change over the

last 3 decades. It is located around 5 meters deep at the coastal line, between 20

to 30 meters inland.

Based on the analysis of results from the studies previously carried out, it is worth

mentioning that generally there are no noticeable variations; although the water

level responds clearly to rainfall, and is more significant in the cyclone seasons

presented periodically every 6 to 10 years.

The geographic location of the Todos Santos Aquifer has an advantage because it

is in a zone where the incidence and nearness of hurricanes is presented year by

year, and leaves precipitation which maintains its stability, as well as an important

source of replenishment, such as the Santa Ins Dam, the largest of the 5 dams

built in the state.


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Recommendations.

Considering that the draught is a generalized problem, our personal

recommendation would be that Todos Santos is a good place in which to invest,

given its weather conditions, as well as the fact that it is a source of surface and

underground water, which gives it an added investment value.

We recommend the re-use of waste water, and in the case of a project expansion,

desalination should be considered.

It is important to actively participate in the care and maintenance of the

underground and spring waters, including to promote the creation of a surveillance

council along with CONAGUA, in order to supervise that the concessional volume

extractions are in accordance with the authorization granted, and to avoid a

possible over-exploitation of the aquifer, which may cause its degradation andsaline intrusion.


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VII. ANNEXES

Form #CAN-01-013, authorization for transfer of registration titles, this

document details the requirements of the 13 PAGES-procedure.

Drawing 1 of 2, includes the location of wells and springs on the INEGI chart,

scale 1:50,000.

Drawing 2 of 2, includes the location of wells and springs on Google images.

Documents

GEO-HYDROLOGICAL SYNOPSIS OF THE TODOS SANTOS AQUIFER