Manmade lakes and reservoirs created by constructing dams across various rivers in the Western Ghats contribute to a sizeable proportion of artificial wetlands of the state.

Ashtamudi Lake: Ashtamudi Lake, which flows through Kollam district of Kerala, is one of the largest and deepest wetland ecosystems. The lake is shaped like a palm tree or, as it is referred mostly by the locals, as an octopus. Ashtamudi Wetland was included in the list of wetlands of international importance, as defined by the Ramsar Convention for the conservation and sustainable utilization of wetlands. The lake is the source of livelihood for the people living close to it in fishing, coconut husk retting  for coir  production and inland navigation services.

Ashtamudi Estuary has mangroves Avicennia officinalis, Brugiera gymnorrhiza and Sonneratia caseolaris as also 43 species of marshy and mangrove associates including two endangered species Syzygium travancoricum (endangered species according to the Red Data Book of Indian Plants) and Calamus rotang in the Terrestrial system.. These species offer excellent scope for development of marine bioreserve to promote eco-tourism in the estuarine of the lake.    The lake supports 57 species of avifauna, of which 6 are migratory and 51 resident species. It is also reported that about 40 species of wetland-dependent birds are recorded in the lake, out of which 45% are long-distance migrants. Terns, plovers, cormorants, and herons are most abundant birds in the lake.

Punnamada Lake: Punnamada Lake is a part of the Vembanad Lake which is India’s longest lake and the biggest lake in Kerala. The lake spans to a number of districts in Kerala. Hence, it is called by different names at different parts of Kerala. When the lake reaches Kuttanad, it is called Punnamada Lake or Punnamada Kayal. The Port of Kochi is located around two islands the Willingdon Island and Vallarpadam which lie in this lake. The lake is called Kochi Lake in this part of Kerala. The famous Annual Nehru Trophy Race of Kerala is also conducted on parts of Punnamada Lake. The Kochi Lake is a portion of the Vembanad Lake, which is located in and around the Kochi Mainland.

Vembanadu Lake:  Vembanad Lake, the largest lake in Kerala, is called by different names, as it flows through different districts of the state. Since Vembanad Lake is the longest lake in Kerala, the much celebrated Nehru Trophy Boat Race is also conducted on a major portion of this lake. The race is conducted at Kuttanad region, where the Lake is known as Punnamada Lake. The lake is in itself an ecosystem and spans an area of 2033 sq.km. The lake has also the pride to be known as the largest wetland ecosystem in India. Vembanad Lake is bordered by three major districts of Kerala, namely Alappuzha, Kottayam, and Ernakulam. The lake lies at the sea level and is separated by the Arabian Sea just by a barrier Island. The lake spans 14km at its widest point. The lake is a major source of fresh water for the state. It helps in the irrigation of a large part of the farming area of the state.

Akkulam Lake: Akkulam Lake is a serene and peaceful picnic spot in Kerala. The Akkulam Lake is, in fact, a part of the Veli Lake, where it joins with the sea. The splendor of the lake is enhanced when it is added on with the scenic beauty of the surrounding Western Ghats. Boating is the most popular water sport which can be enjoyed in Akkulam Lake. This is a prime picnic spot for both domestic and international tourists.

Mananchira Lake: Mananchira is a manmade freshwater lake, which is situated at the centre of the city of Kozhikode (Calicut). The lake is 3.49 acres (14,120 m²) in area, is rectangular in shape and is fed by a natural spring.  The lake was earlier built as a bathing pool by Zamorin Mana Vikrama, who used to be the feudal ruler of Kozhikode in 14^th century. The laterite which was obtained after excavating the pool was used to build two palaces at the east and west end of the pool. The water of the lake is kept entirely for drinking purpose.

Veeranpuzha Lake:  Veeranpuzha Lake is located in Cochin district of Kerala. This is a part of the northern extension of Vembanad Lake. Vembanad Lake itself is called Veeranpuzha in Vyppen Island. The place is devoid of any human habitation. The main reason behind its being devoid of human settlement is the non-availability of fresh water. The saline tolerant Pokkali rice is cultivated in the fields gathered around the banks of Veeranpuzha. Pokkali is cyclic organic cultivation method.

Vellayani Lake:  Vellayani Lake, or Vellayani Kayal as it is better known in Kerala, is the largest fresh water lake in Trivandrum. It is best to visit the lake on moonlit nights, as the rays of the moon are reflected from the surface of the placid water of the lake. The lake water is extensively used for drinking and irrigational purposes.

Paravur Kayal: Paravur Kayal is comparatively a much smaller lake than its other counterparts in Kerala. It occupies an area of just 6.62sqkm. The lake is the end point of the Ithikkara River, and is watered by the river too. The lake was linked to Edava Kayal and Ashtamudi Kayal as division of the Trivandrum - Shoranur canal scheme since the late 19^th century.

Sasthamkotta Lake: Sasthamkotta Lake is also categorized by the modern geologists as a wetland ecosystem. This is considered as the largest fresh water lake in Kerala. The lake is named after the ancient Sastha temple (a pilgrimage centre) located on its bank. The lake caters to the drinking water needs of the half a million people of the Quilon district and also doubles as providing fishing resources to the people here. The lake is a habitat for a large number of Avifauna and Aqua Fauna. There are no visible tributaries feeding the lake but springs at the bottom of the lake are stated to be one of the source which supply water throughout the year; volume of water in the lake is estimated to be of the order of 22.4 million cum.

Pookode Lake: Pookode Lake is a scenic freshwater lake in the Wayanad district of Kerala. The lake is surrounded by forests and mountain slopes at an altitude of 2100 meters above sea level and having an area of 13 acre and 40 meter deep.  There are groups of Blue water lily flowers scattered here and there in the lake. There have been recent modernizations to beautify this place. The natives sell natural handmade items here which are made up of fibers like jute or bamboo. Recent commercial modernisations have removed some of its wild charm. Panamaram, the rivulet which ultimately becomes Kabani River, originates from the Pookode Lake. It is spread across an area of 8.5 hectares and with a maximum depth of 6.5 metres.