Realization of hydraulics design of aquaculture facilities with integration  of irrigation systems in the upper Blue Nile basin: Challenges and opportunities for aquaculture development

The general objective of this paper is to review hydraulics design  of aquaculture  facilities  with  integration  of irrigation  systems and  assessment of potentials, opportunities and  approaches. It also disuses the major reasons why an irrigation engineer in the past had little  or  no  concern  to  include  aquaculture  facility  designs  when dealing with the  hydraulic design of irrigation structures in fishable- rivers..   Review  of   the   literature  showed  that   aquaculture  is  a relatively new and underdeveloped farming practice compared to agriculture and  animal husbandry in Ethiopia and  even  in many parts of  the   word  which  can   be   one   reason  why  irrigation  engineers ignored  fish  facilities  earlier.  In general  in  spite  of its  positive  social and  environmental attributes which make  aquaculture business an attractive entry  point to improve the  livelihoods of the  poor  in rural development  strategies,  the  large  potential  contribution  of aquaculture  was  unappreciated  and   ignored  by  most  agriculture, water  resource, rural development professionals and  even  by policy makers.  This   paper  also   includes   results   of   reviewed   design documents of  the  major irrigation  diversion or  dams and  depicted how  large  the  potential  water   access  in  Tana   basin  is  available currently  for  aquaculture  business.  Based on  the  review  of  detail designs  of irrigation  and  hydropower projects  in  the  basin,  currently Tana   basin  has  dependable  water   bodies  of   3,906ha  artificial reservoirs,  310,000ha  natural  lake  reservoir,  279.4   km  of  main canals  and  708km  of  secondary canals  that  could  be  utilized  for aquaculture purposes. Though  ponds and  tanks have  been expected more  in the  basin because of their prime resources for freshwater aquaculture development, no practice was found in the basin except for some experimental cases near  the  lake. In conclusion, the  paper also  discusses  the  future  perspective  of  aquaculture  development and   its  research,  legal,  institutional  and   policy  requirements  in creating awareness and finally knowledge in the field.