Rasterio installation failing

I am trying to update my rasterio version from 0.25 to 0.32 on a python 2.7 installation, but running up against foll. issue. Any info on how to fix it?

 Running setup.py clean for rasterio
Failed to build rasterio
Installing collected packages: rasterio
  Found existing installation: rasterio 0.25.0
    Uninstalling rasterio-0.25.0:
      Successfully uninstalled rasterio-0.25.0
  Running setup.py install for rasterio: started
    Running setup.py install for rasterio: finished with status 'error'
    Complete output from command C:\Anaconda64\python.exe -u -c "import setuptools, tokenize;__file__='c:\\users\\rit\\appdata\\local\\temp\\pip-build-dvzvvz\\rasterio\\setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record c:\users\rit\appdata\local\temp\pip-4qousd-record\install-record.txt --single-version-externally-managed --compile:
    running install
    running build
    running build_py
    creating build
    creating build\lib.win-amd64-2.7
    creating build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\coords.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\crs.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\dtypes.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\enums.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\errors.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\features.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\fill.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\five.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\profiles.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\sample.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\tool.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\transform.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\vfs.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\warnings.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\warp.py -> build\lib.win-amd64-2.7\rasterio
    copying .\rasterio\__init__.py -> build\lib.win-amd64-2.7\rasterio
    creating build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\bands.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\calc.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\convert.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\features.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\helpers.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\info.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\main.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\merge.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\options.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\overview.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\sample.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\warp.py -> build\lib.win-amd64-2.7\rasterio\rio
    copying .\rasterio\rio\__init__.py -> build\lib.win-amd64-2.7\rasterio\rio
    creating build\lib.win-amd64-2.7\rasterio\tools
    copying .\rasterio\tools\mask.py -> build\lib.win-amd64-2.7\rasterio\tools
    copying .\rasterio\tools\merge.py -> build\lib.win-amd64-2.7\rasterio\tools
    copying .\rasterio\tools\__init__.py -> build\lib.win-amd64-2.7\rasterio\tools
    running egg_info
    writing requirements to rasterio.egg-info\requires.txt
    writing rasterio.egg-info\PKG-INFO
    writing top-level names to rasterio.egg-info\top_level.txt
    writing dependency_links to rasterio.egg-info\dependency_links.txt
    writing entry points to rasterio.egg-info\entry_points.txt
    warning: manifest_maker: standard file '-c' not found

    reading manifest file 'rasterio.egg-info\SOURCES.txt'
    writing manifest file 'rasterio.egg-info\SOURCES.txt'
    running build_ext
    building 'rasterio._base' extension
    creating build\temp.win-amd64-2.7
    creating build\temp.win-amd64-2.7\Release
    creating build\temp.win-amd64-2.7\Release\rasterio
    C:\Users\rit\AppData\Local\Programs\Common\Microsoft\Visual C++ for Python\9.0\VC\Bin\amd64\cl.exe /c /nologo /Ox /MD /W3 /GS- /DNDEBUG -IC:\Anaconda64\lib\site-packages\numpy\core\include -IC:\Anaconda64\include -IC:\Anaconda64\PC /Tcrasterio/_base.c /Fobuild\temp.win-amd64-2.7\Release\rasterio/_base.obj
    _base.c
    rasterio/_base.c(263) : fatal error C1083: Cannot open include file: 'cpl_conv.h': No such file or directory
    error: command 'C:\\Users\\rit\\AppData\\Local\\Programs\\Common\\Microsoft\\Visual C++ for Python\\9.0\\VC\\Bin\\amd64\\cl.exe' failed with exit status 2

    ----------------------------------------
  Rolling back uninstall of rasterio