The Housing Fee is a tax that is 5% of your total rental agreement for the year. You can choose to pay it in a lump sum or over 12 months. The tenant is responsible for paying it. Depending on your housing allowances or utilities allowances that you company provides you, reimbursement is possible. My company reimburses for the full amount. I've heard some companies reimburse half and others have it built into the utilities allowance. You need to contact your HR dept. to find out what the company policy is.
It could be added to DEWA bill and is normally paid by the Tenant. However, you may be lucky and it is not. We just left our apartment in The Greens after more than 1 year..never paid it on the monthly bill and nobody claimed it when we paid the final DEWA bill when we moved out.