Here is a combined list of all the helpline numbers and rescue team numbers. Which may be helpful to people at Chennai. We have tried our best to authenticate the numbers below.

Navy Helpine Number

 +914425394240 is Navy Helpline number in Chennai Source

Army Helpline numbers 

1st Regional Office (Tiruvottiyur) - 9445190001
2nd Regional Office(Manali) - 9445190002
3rd Regional Office (Madhavaram) - 9445190003
4th Regional Office(Tondiarpet) - 9445190004
5th Regional Office(Royapuram)- 9445190005
6th Regl Office(Thiru. Vi. Ka. Nagar) - 9445190006
7th Regional Office(Ambattur) - 9445190007
8th Regional Office(Annanagar) - 9445190008
9th Regional Office(Teynampet) - 9445190009
10th Regional Office(Kodambakkam) - 9445190010
11th Regional Office (Valasaravakkam)- 9445190011
12th Regional Office(Alandur) - 9445190012
13th Regional Office (Adyar)- 9445190013
14th Regional Office(Perungudi) - 9445190014
15th Regional Office(Sholinganallur) - 9445190015

Boat services

NTL boat Helpline 7708068600

Ola - 7708068600

Royapuram 9445190005
TVK Ngr 9445190006
Ambattur 9445190007
Anna Ngr 9445190008 

Private Boat Helpline and Rescue — 9445869843/47, 09962634858.

Other Helpline Numbers:

Emergency Toll Free No: 1913
State Emergency: 1070
District Emergency: 1077
Electricity: 1912
Sewage overflow - 45674567, 22200335
Fire & Rescue: 101
Ambulance: 108
The Navy has deployed boats in Adyar and helpline number is 044-25394240
Tree fall, Water logging - 1913

Accommodation:

T-Nagar

People stuck in T.Nagar(surrounding areas) and OMR , pl DM me your details. You can stay at my hotel. #chenairains

— prashanth vasan (@shaanth007) December 1, 2015

Kolathur

accommodation at Sri Arunodayam Trust for 50 families.Pls contact. No 35 Sivanada nagar, kolatur.Ph: 9444915803 Pleaseshare #PrayforChennai

— Archana (@ArchanaArchuu) December 1, 2015

Tondiarpet

People affected near tondairpet: Prince flats to accomdate 100 people Contact Chetan 9840191291 #chennairains @RJ_Balaji @DhivyaDharshini

— kumaran vs (@kumarancool4) December 1, 2015

Vandalur: Food & Shelter

Vandalur Abdur Rahman university offers food and shelter to the affected people on the GST. Nation Disaster Relief Team camps there.

— Karthigaichelvan S (@karthickselvaa) December 2, 2015

Tambaram/Chrompet

Marundeeshwara kalyanamandapam Anagaputhur is now open for people who need shelter in tambaram ,chrompet,tiruneermalai, area.

— Dhanush (@dhanushkraja) December 2, 2015

Kodambakkam & Saligramam

#Rajini's Ragavendra mandabam n k.bakkam #Vijay's Shoba Hall n s.gramam s opn now4 de needy.Food preparation also n progress. #ChennaiRains

— Johnson PRO (@johnsoncinepro) December 2, 2015

Trains cancelled

Train services that are canceled/diverted from Chennai Central/ Egmore for tod/ Tom #ChennaiRainsHelp #ChennaiRains pic.twitter.com/0KNPi3jPbX

— Surendhar MK (@MadrasBachelor) December 2, 2015