Sienna Reserve is a park at 41 McMahon Drive in Halswell, Christchurch. The linked page is the city council's general news and services page, so we have set it aside.
The directory holds no details of what the reserve offers, its paths, play areas, facilities, access, parking, dogs or children, and no visitor comments beyond the rating. It gives no figures for other parks nearby either, so we can say no more about the reserve than its street and suburb.