This is a large dam in the Coonoor taluk, used for supplying drinking water to Coonoor town. The reservoir and wetland are situated in the upper area with a forest of Acacia, Eucalyptus and some sholas as catchments. The wetland is vast. There is a large water body and then a dry, swampy region. On one side are small wetlands next to the large water body. Some of them as small as a few meters, yet performing the functions of the wetland. Here we found an abundance of insectivorous plants. The insectivorous plants are mostly found in highly nutrient deficit wetlands. The wetland becomes nutrient deficit when the recharge of water does not take place. In a wetland like Raliah adjoining the reservoir recharge is unlikely to happen and so the high density of insectivorous plants.
An interesting feature in the area was the presence of a peat bog. It was small in size, marshy with red scum coating on the soil as well as on the water. It smelled heavily of methane and gaseous emitions. It is surrounded by wattle. Near to this peat swamp was a stream which finally joined the main reservoir.

Biological and Botanical Narrative

The wetland is the source of water to the reservoir. The wetland was dominated by Eriocaulon spp. and Juncus spp. (which was dry).The soil was dry on the surface and wet underground.  Viola and Centella  were found in moist places near the edges. Gentiana quardifaria and an insectivorous plant, Drosera burmanni was found abundant on the black moist soil.
The wetland was surrounded by Wattle and Pine plantation and small patch of shola forest on one side. Sighting of birds like Barn owl, Pond Heron, Egret and Common grass yellow butterfly was seen.
Frogs, water spiders, dragon fly, bees (Apis cerana) were seen near the water course. Signs of cow dung, scat of, Panther, Beer showed the presence of grazing and wildlife in the area. Malabar giant squirrel was sighted in the shola

Numeric Criteria – Water quality

The following table gives the water quality for various parameters.

Permissible limits Observed value
pH 6.5-8.5 7.3
Temperature (0C) 10 15
Coliform Nil Yes
Fluoride 1.0 (max) 0.6
Residual Chloride (mg/l) 0.2 0.2

Phosphorous (mg/l) 0.1
Iron (mg/l) 0.3 1
Hardness (mg/l) 300-600 40
Chlorides (mg/l) 250-1000 212.7
Ammonia 1.5 1
Turbidity(NTU) less than 5-10 10
Remark soft water, low fluoride and chloride content, presence of coliform According to the tests the water in the reservoir is very soft with fluoride and chlorine content less than the prescribed limits. Presence of Coliform bacteria was seen, which is known to cause water-borne diseases like typhoid, cholera and dysentery.


The reservoir and the adjoining wetland are situated in a forest of pine and shola trees. The wilderness and serenity of the place provide an ideal picnic spot for the local people in Coonoor, Ooty and Kotagiri.

A lot of tourist activity could be noticed. There was litter in the form of plastics cups, bottles and food packets. We also noticed burning of fuel consumption for cooking and fire camp activities. Fishing activity by the local people was also witnessed by the team   and on the edges of the reservoir surrounded by forests fuel wood collection was also noticed.

Future course of action

The team plans to approach the local authorities to enforce certain measures to stop degradation of the area which could happen due to excessive tourism, fishing and fuelwood collection activities. A local management plan could be evolved with local participation which provides for conserving the wetland and maintaining the water quality.

For eg the following could be part of the plan:

– Dust-bins should be placed in the areas and no cooking activities by the tourists should be allowed.

– The rules regarding fishing and fuel wood collection should also be strictly followed

– The reservoir should be fenced to stop access to people for fishing and other activities like swimming.