Harvest collects and processes a wide range of data pertaining to
ground and surface water in order to gain a full understanding of
the area. It is from these scientific investigations that we go forward
with our remediation efforts.
 Since
1996, the water resources (hydrology and groundwater) team is monitoring
the water levels and quality parameters over a 200 sq. km area,
covering the Auroville plateau and the wider bioregion. After the monsoons
the fluctuation of groundwater levels and tank water correlating
with the rainfall is measured, as well as the runoff in the hydrological
network. Hydrological data is incremented using an automatic metrological
station, and detailed topography of tanks, channels and ayacut
areas is laid out using high accuracy differential GPS technology. All
of this data is compiled in a database that also includes sociological
information gathered by Harvest's social team. The collected information
is processed in Geographical Information Systems (GIS) for further
modeling. This provides us with thorough and up-to-date tools for
watershed management.
The Groundwater Situation in Auroville and it's Bioregion with
the latest research done through the UNESCO HELP Basin Program
Our monitoring of water levels and water quality in the wells of
this region shows a tremendous decline in the level of the water
tables due chiefly to over extraction (up to 45 m over 30 years
in some locations) and an alarming increase of salinity in the groundwater,
particularly in the Vanur aquifer, the main aquifer of the region.
While the water levels are going down
the salinity levels are increasing. The salinity rates throughout the
aquifer exceed the levels for safe drinking water, and in some
areas exceed the levels for safe irrigation water set by the World
Health Organization
An ongoing collaborative research program between Harvest and a
team of French scientists that has been recently integrated into
the UNESCO HELP Basin Program, has been conducting research on the
source of this salinisation. It has been discovered that the a ctual
cause of salinisation of this aquifer is not yet from sea water intrusion
but from several other factors including: upward leakage from an
aquifer below Vanur, the input of brackish water into the Kaluvelly
swamp and the infiltration of concentrated waters by evaporation.
This basic figure represents a West to East (left
to right) cross section of the Vanur Aquifer with the movement of
the seawater in red, orange and yellow lines. It is based on the
results of a 1D hydrodynamic model of the seawater/freshwater movement
built with the available geological and hydraulic data.
The simple hydro-dynamic simulation model of the interface between
seawater and freshwater shows that seawater intrusion can be expected
to occur within 3 to 20 years after 2000 depending on the value of
unfixed parameters (porosity) and boundary conditions (recharge rate)
. Moreover, the model shows that some intrusion should have already
occurred. The reason that it has not must be studied further (one
possibility is a fault).
All the data shows that further seawater
intrusion is very likely especially with such high extraction rates.
If left unattended it could endanger the entire south part of the
Kaluvelly watershed, and therefore Auroville. Presently, remediation
of seawater intrusion cannot be achieved during a human lifetime.
The consequences of such intrusion would be disastrous, as water
for irrigation and drinking purposes would become scarce in the villages
and the township of Tindivanam would see its main source of drinking
water badly affected.
Harvest has undertaken the following projects:
Kaluvelly and Pondicherry Sedimentary Coastal
Basin, a UNESCO HELP Program
This is a large pilot program undertaken
to create a framework for successful sustainable water management in
this basin. Presently, the hydrodynamic functioning of the whole system
is poorly known and no water management laws have been enacted nor
applied. The aim is to create an action-research and operational project
to develop new methodologies in the field of: Hydrology and hydrogeology;
tank rehabilitation; coastal area water management; policy development;
environmental and water management awareness; and social development.
The main objectives are: To understand present circumstances from a
hydrological and socio-economical point of view; to quantify the fresh
water resources and their time evolution in order to prevent salinisation
in the aquifers; to define methodologies of system evaluation that
could be applied and extended to other sedimentary basins; and to find
good arguments to promote the introduction of water management rules/laws .
Hydrological network of the 1400 km 2 project area
This
Program is a continuation and expansion of a scientific collaboration
that has been built between Harvest and a team of French scientists
(Paris 6 University, Tours University , Rennes University and IPGP)
to study the origin of salinisation in the Vanur aquifer of the sedimentary
basin of Kaluvelly . Since January 1999, a team of French scientists
coordinated by Ms. Sophie Violette (Pr. Hydrogeology) and Ms. Nathalie
Gassama (Pr. Hydro-geochemistry) have worked together to assess the “Source
of Salinity and Groundwater Circulation in Kaluvelly Watershed”.
The first part, dedicated to the hydro-geochemistry resulted in the
discovery of the current sources of salinisation (see the description
of the groundwater situation up top). Currently, since October 2003,
the hydrology and the hydrogeology phases of the study are being
conducted, with the participation of Pr. De Marsily, an internationally
awarded hydrogeologist and engineer.
This program also involves many partners
including: UMR–Sysphe UPMC
- France, CGWB – Chennai, TRPP-PWD - Pondicherry , PWD-SGWB - Chennai,
and TWAD – Villupuram District to name some of them.
Integrated Sustainable water management for the International Zone,
Auroville
A document was put together by Harvest to create a base for future
planning and development for the International Zone. The purpose
of this document was to initiate reflections on Integrated Sustainable
Water Management for the International Zone aiming at environmentally
sound development. It analyzed the features of the International
Zone systematically and consequently the solutions fitting with the
needs and defined criteria.
This research brought to light the absolute need to incorporate
the village of Kottakarai , which is partly inside the International
Zone, into the development plans. In terms of water management, Kottakarai
is a very sensitive area due to its high water tables and its initial
position in the chain of tanks in the Kaluvelly watershed. Pollution
from garbage waste and human excrement pose a threat to the health
of the people and of this water system. A pilot water and sanitation
project for this village is currently in the works. The hope is to
replicate this in the surrounding villages positively affecting the
health of the entire watershed.
Industrial wastewater management, Anglo-French Textiles
A pre-feasibility study on wastewater management and sludge disposal
for Anglo-French Textiles was conducted in collaboration with Cynergy
(Centre for Scientific Research). The solutions advocated tertiary
treatment for the reuse of wastewater and power generation by sludge
incineration in a gasifier.
Groundwater assessment, E.I.D Parry (I) Ltd
A preliminary study was carried out for the E.I.D Parry sugar mills
at Nellikuppam to assess the groundwater and the upcoming salinity
threat to the cane growing areas.
The study included the quantification of groundwater extraction
and water quality parameters covering 996 sq.km. The results showed
degradation in both quality and quantity of the water, and it was
forecasted that unless corrective measures would be taken rapidly,
sustainability of the activities of the mills would be in jeopardy.
Development of a Participatory Methodology in Hydro geological
Extension, Tamil Nadu Council for Science & Technology
On grant by the Tamil Nadu Council for Science & Technology,
Harvest has developed and completed a program of participatory hydro
geological extension in which village youths are conducting hydrological
surveys and assessments in 14 local villages. Through these youth
a network of rainfall assessment stations for this area have been
created.
Groundwater Resources for the Wider Auroville Area, Pondicherry
Engineering College
This was a joint research project started in 2001 with Pondicherry
Engineering College , the Auroville Planning and Development Council
and Harvest to assess the Groundwater resources for the wider Auroville
Area. The outcome was an extensive report that is now available. GIS
Project, Indian Space Research Organization, Govt of India , Bangalore In
the light of the ISRO promoting different schemes for India 's natural
resources utilization, conservation, restoration and educational
outreach programmes, a proposal was born to create a GIS office and
training facility at Auroville as a collaborative effort between
ISRO and Auroville. The GIS project is being executed under the direct
authority of the Auroville Foundation with expertise support from
ISRO.
The collapse of the Casuarina market has provoked a massive
shift in the cropping pattern of the coastal area and people tend
to cultivate Paddy, groundnut, ragi and other irrigated crops.
Hence an urgent need to understand the cropping pattern of the region
has been realized.
The project commenced in January 2000 and is involving
various working group of Auroville. Harvest is concentrating
on the water and agricultural applications in this project. Data
(spatial and non-spatial) acquisition and integration as well as
processing are well underway.
Satellite view of the Auroville area from ISRO Bangalore March
1999. The Kaluvelly swamp is in the top right hand corner and the
utility canyon going into Auroville is in the bottom right hand corner.
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