TEXT datatype length

CREATE TABLE TABTEXT
(
    EMail TEXT
)

Insert into TABTEXT 
Select 'a'

Select COL_LENGTH('TABTEXT','EMail') as ColumnLength
Select EMail,Datalength(EMail) as DataLength From TABTEXT 

In sp_help if you give a tableName...Additional result set returned on column objects
and Length is Nothing but the column length given in Bytes...

Col_Length:Returns the defined length, in bytes, of a column.The 16 what you are getting is nothing but column length of EMail column in Bytes in that TABTEXT table, by Default it takes the length of text column as 16... If you enter a some data into that column u can check the length in bytes by using DataLength... if you want to check the length in characters u can declare a variable as varchar or nvarchar and assign the column value to that variable and use len on that variable..

The output for the above queries is

ColumnLength
------------
  16

EMail	DataLength
-----   ----------
 a	 1

Hope this Answers your Question....
Check this links http://msdn.microsoft.com/en-us/library/ms187335.aspx[sp_help]
http://msdn.microsoft.com/en-us/library/ms188732.
http://msdn.microsoft.com/en-us/library/ms173486.aspx