diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index dc34cd36..83c15c77 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -20,7 +20,7 @@ jobs:
     strategy:
       matrix:
         python-version:
-          - "3.8"
+          - "3.9"
     steps:
       - name: Cancel previous runs
         uses: styfle/cancel-workflow-action@0.11.0
diff --git a/.readthedocs.yml b/.readthedocs.yml
index 5138f8f0..96a35289 100644
--- a/.readthedocs.yml
+++ b/.readthedocs.yml
@@ -19,7 +19,7 @@ build:
       - sphinx-apidoc -o docs/apidoc --private --module-first xhydro
 
 conda:
-  environment: environment-docs.yml
+  environment: environment-dev.yml
 
 python:
   install:
diff --git a/HISTORY.rst b/HISTORY.rst
index 7aa6f30d..cdb37d21 100644
--- a/HISTORY.rst
+++ b/HISTORY.rst
@@ -35,6 +35,7 @@ Internal changes
     * Automated testing with tox now updated to use v4.0+ conventions.
     * Removed all references to travis.ci.
 * Deployments to TestPyPI and PyPI are now run using GitHub Workflow Environments as a safeguarding mechanism. (:pull:`28`).
+* Various cleanups of the environment files. (:issue:`23`, :pull:`30`).
 
 0.1.2 (2023-05-10)
 ------------------
diff --git a/MANIFEST.in b/MANIFEST.in
index e0f7b6b7..988f455d 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -3,8 +3,6 @@ include CONTRIBUTING.rst
 include HISTORY.rst
 include LICENSE
 include README.rst
-include requirements_dev.txt
-include requirements_docs.txt
 include .zenodo.json
 
 recursive-include docs *.rst conf.py Makefile make.bat *.jpg *.png *.gif
@@ -22,5 +20,5 @@ exclude .readthedocs.yml
 exclude .yamllint.yaml
 exclude Makefile
 exclude environment.yml
-exclude environment-docs.yml
+exclude environment-dev.yml
 exclude tox.ini
diff --git a/environment-dev.yml b/environment-dev.yml
new file mode 100644
index 00000000..296f255d
--- /dev/null
+++ b/environment-dev.yml
@@ -0,0 +1,32 @@
+name: xhydro-dev
+channels:
+  - conda-forge
+dependencies:
+  - python >=3.9,<3.11
+  # Don't forget to sync the changes here with environment.yml!
+  # Main packages
+  # Dev
+  - bump2version
+  - coveralls
+  - furo
+  - ipykernel
+  - ipython
+  - jupyter_client
+  - nbsphinx
+  - nbval
+  - pandoc
+  - pooch
+  - pre-commit
+  - pytest
+  - pytest-cov
+  - sphinx
+  - sphinx-autoapi
+  - sphinxcontrib-napoleon
+  - sphinx-codeautolink
+  - sphinx-copybutton
+  - pip
+  # Testing
+  - tox >=4.0
+  # Packaging
+  - build
+  - wheel
diff --git a/environment-docs.yml b/environment-docs.yml
deleted file mode 100644
index b7a243d1..00000000
--- a/environment-docs.yml
+++ /dev/null
@@ -1,14 +0,0 @@
-name: xhydro
-channels:
-  - conda-forge
-  - defaults
-dependencies:
-  - sphinx
-  - furo
-  - mock
-  - nbsphinx
-  - pandoc
-  - sphinx-autoapi
-  - sphinx-codeautolink
-  - sphinx-copybutton
-  - sphinxcontrib-napoleon
diff --git a/environment.yml b/environment.yml
index 25affbc6..6055f14a 100644
--- a/environment.yml
+++ b/environment.yml
@@ -2,36 +2,4 @@ name: xhydro
 channels:
   - conda-forge
 dependencies:
-  - python >=3.10,<3.11
-  - IPyKernel
-  - bottleneck >=1.3.1
-  - cartopy
-  - cftime >=1.4.1
-  - cf_xarray >=0.6.1
-  - dask >=2.6
-  - furo
-  - geopandas
-  - geoviews
-  - h5netcdf
-  - hvplot
-  - intake
-  - intake-geopandas
-  - intake-xarray >=0.6.1
-  - jsonpickle
-  - matplotlib-base
-  - nbsphinx
-  - netCDF4
-  - numba
-  - numpy >=1.16.0
-  - pymannkendall
-  - rioxarray
-  - s3fs >=2022.7.0
-  - scipy >=1.2
-  - sphinx
-  - sphinx-autoapi
-  - sphinx-codeautolink
-  - sphinx-copybutton
-  - sphinxcontrib-napoleon
-  - xarray >=0.17.0
-  - xclim >=0.43.0
-  - zarr >=2.11.1
+  - python >=3.9,<3.11
diff --git a/requirements_dev.txt b/requirements_dev.txt
deleted file mode 100644
index 86782b21..00000000
--- a/requirements_dev.txt
+++ /dev/null
@@ -1,16 +0,0 @@
-Click
-black>=23.3.0
-build
-bump2version
-coverage
-coveralls
-flake8
-isort>=5.12.0
-pip
-pre-commit
-pytest
-pytest-cov
-tox
-twine
-watchdog
-wheel
diff --git a/requirements_docs.txt b/requirements_docs.txt
deleted file mode 100644
index 4eb3499c..00000000
--- a/requirements_docs.txt
+++ /dev/null
@@ -1,10 +0,0 @@
-furo
-ipykernel
-ipython
-jupyter_client
-nbsphinx
-pandoc
-sphinx
-sphinx-click
-sphinx-codeautolink
-sphinx-copybutton
diff --git a/setup.py b/setup.py
index fcbcbf3a..105be109 100644
--- a/setup.py
+++ b/setup.py
@@ -7,38 +7,9 @@
 with open("README.rst") as readme_file:
     readme = readme_file.read()
 
-requirements = [
-    "bottleneck>=1.3.1",
-    "cartopy",
-    "cf-xarray>=0.6.1",
-    "cftime>=1.4.1",
-    "dask[array]>=2.6",
-    "geopandas",
-    "h5netcdf",
-    "intake-xarray>=0.6.1",
-    "jsonpickle",
-    "numba",
-    "numpy>=1.16.0",
-    "pandas>=0.23",
-    "pint>=0.10",
-    "pyarrow",
-    "pyyaml",
-    "s3fs>=2022.7.0",
-    "scipy>=1.2",
-    "xarray>=0.17.0",
-    "xclim>=0.43.0",
-    "zarr>=2.11.1",
-]
+requirements = []
 
-test_requirements = ["pytest>=3"]
-
-docs_requirements = [
-    dependency for dependency in open("requirements_docs.txt").readlines()
-]
-
-dev_requirements = [
-    dependency for dependency in open("requirements_dev.txt").readlines()
-]
+dev_requirements = ["pytest", "pytest-cov"]
 
 setup(
     author="Thomas-Charles Fortier Filion",
@@ -69,9 +40,7 @@
     name="xhydro",
     packages=find_packages(include=["xhydro", "xhydro.*"]),
     test_suite="tests",
-    tests_require=test_requirements,
     extras_require={
-        "docs": docs_requirements,
         "dev": dev_requirements,
     },
     url="https://github.com/TC-FF/xhydro",