diff --git a/Gemfile b/Gemfile
index 3c7f41916..2e10ff81d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -12,6 +12,7 @@ gem 'anchored'
 gem 'bcrypt'
 gem 'bootsnap', '>= 1.4.4', require: false # Reduces boot times through caching; required in config/boot.rb
 gem 'browser'
+gem 'charlock_holmes'
 gem 'chartkick'
 gem 'chunky_png'
 gem 'clamav-client', require: 'clamav/client'
diff --git a/Gemfile.lock b/Gemfile.lock
index eb21c74b0..5a1f455c1 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -155,6 +155,7 @@ GEM
       marcel (~> 1.0)
       nokogiri (~> 1.10, >= 1.10.4)
       rubyzip (>= 1.3.0, < 3)
+    charlock_holmes (0.7.7)
     chartkick (3.4.2)
     childprocess (3.0.0)
     choice (0.2.0)
@@ -793,6 +794,7 @@ DEPENDENCIES
   capybara-email
   capybara-screenshot
   capybara-selenium
+  charlock_holmes
   chartkick
   chunky_png
   clamav-client
diff --git a/app/controllers/new_administrateur/groupe_instructeurs_controller.rb b/app/controllers/new_administrateur/groupe_instructeurs_controller.rb
index ce51452e9..23086104f 100644
--- a/app/controllers/new_administrateur/groupe_instructeurs_controller.rb
+++ b/app/controllers/new_administrateur/groupe_instructeurs_controller.rb
@@ -170,7 +170,10 @@ module NewAdministrateur
         redirect_to admin_procedure_groupe_instructeurs_path(procedure)
 
       else
-        groupes_emails = CSV.new(group_csv_file.read.force_encoding("UTF-8"), headers: true, header_converters: :downcase)
+        file = group_csv_file.read
+        # find the original encoding to avoid encoding errors
+        base_encoding = CharlockHolmes::EncodingDetector.detect(file)
+        groupes_emails = CSV.new(file.encode("UTF-8", base_encoding[:encoding], invalid: :replace, replace: ""), headers: true, header_converters: :downcase)
           .map { |r| r.to_h.slice('groupe', 'email') }
 
         groupes_emails_has_keys = groupes_emails.first.has_key?("groupe") && groupes_emails.first.has_key?("email")
diff --git a/app/javascript/components/shared/mapbox/MapStyleControl.jsx b/app/javascript/components/shared/mapbox/MapStyleControl.jsx
index a94c07aa7..f6bc98a04 100644
--- a/app/javascript/components/shared/mapbox/MapStyleControl.jsx
+++ b/app/javascript/components/shared/mapbox/MapStyleControl.jsx
@@ -48,6 +48,9 @@ export function useMapStyle(
   const enabledLayers = Object.entries(layers).filter(
     ([, { enabled }]) => enabled
   );
+  const layerIds = enabledLayers.map(
+    ([layer, { opacity }]) => `${layer}-${opacity}`
+  );
   const style = useMemo(
     () =>
       getMapStyle(
@@ -57,13 +60,10 @@ export function useMapStyle(
           enabledLayers.map(([layer, { opacity }]) => [layer, opacity])
         )
       ),
-    [
-      styleId,
-      enabledLayers.map(([layer, { opacity }]) => `${layer}-${opacity}`)
-    ]
+    [styleId, layerIds]
   );
 
-  useEffect(() => onStyleChange(), [styleId, cadastreEnabled]);
+  useEffect(() => onStyleChange(), [styleId, layerIds, cadastreEnabled]);
 
   return { style, layers, setStyle, setLayerEnabled, setLayerOpacity };
 }
diff --git a/app/models/procedure_presentation.rb b/app/models/procedure_presentation.rb
index 309b63d31..066ef42ca 100644
--- a/app/models/procedure_presentation.rb
+++ b/app/models/procedure_presentation.rb
@@ -22,6 +22,8 @@ class ProcedurePresentation < ApplicationRecord
   TYPE_DE_CHAMP = 'type_de_champ'
   TYPE_DE_CHAMP_PRIVATE = 'type_de_champ_private'
 
+  FILTERS_VALUE_MAX_LENGTH = 100
+
   belongs_to :assign_to, optional: false
 
   delegate :procedure, to: :assign_to
@@ -30,6 +32,7 @@ class ProcedurePresentation < ApplicationRecord
   validate :check_allowed_sort_column
   validate :check_allowed_sort_order
   validate :check_allowed_filter_columns
+  validate :check_filters_max_length
 
   def fields
     fields = [
@@ -282,6 +285,14 @@ class ProcedurePresentation < ApplicationRecord
     end
   end
 
+  def check_filters_max_length
+    filters.values.flatten.each do |filter|
+      if filter['value']&.length.to_i > FILTERS_VALUE_MAX_LENGTH
+        errors.add(:filters, :too_long)
+      end
+    end
+  end
+
   def field_hash(label, table, column)
     {
       'label' => label,
diff --git a/app/views/instructeurs/procedures/show.html.haml b/app/views/instructeurs/procedures/show.html.haml
index 062af95c5..5e2553b7b 100644
--- a/app/views/instructeurs/procedures/show.html.haml
+++ b/app/views/instructeurs/procedures/show.html.haml
@@ -86,7 +86,7 @@
             = select_tag :field, options_for_select(@displayed_fields_options)
             %br
             = label_tag :value, "Valeur"
-            = text_field_tag :value
+            = text_field_tag :value, nil, maxlength: ProcedurePresentation::FILTERS_VALUE_MAX_LENGTH
             = hidden_field_tag :statut, @statut
             %br
             = submit_tag "Ajouter le filtre", class: 'button'
diff --git a/spec/controllers/new_administrateur/groupe_instructeurs_controller_spec.rb b/spec/controllers/new_administrateur/groupe_instructeurs_controller_spec.rb
index d3308a54d..bc1bcf04e 100644
--- a/spec/controllers/new_administrateur/groupe_instructeurs_controller_spec.rb
+++ b/spec/controllers/new_administrateur/groupe_instructeurs_controller_spec.rb
@@ -365,6 +365,16 @@ describe NewAdministrateur::GroupeInstructeursController, type: :controller do
       it { expect(flash.alert).to eq("Import terminé. Cependant les emails suivants ne sont pas pris en compte: kara") }
     end
 
+    context 'when the content of csv contains special characters' do
+      let(:csv_file) { fixture_file_upload('spec/fixtures/files/groupe_avec_caracteres_speciaux.csv', 'text/csv') }
+
+      before { subject }
+
+      it { expect(procedure.groupe_instructeurs.pluck(:label)).to eq(["défaut", "Auvergne-Rhône-Alpes", "Vendée"]) }
+      it { expect(flash.notice).to be_present }
+      it { expect(flash.notice).to eq("La liste des instructeurs a été importée avec succès") }
+    end
+
     context 'when the csv file length is more than 1 mo' do
       let(:csv_file) { fixture_file_upload('spec/fixtures/files/groupe-instructeur.csv', 'text/csv') }
 
diff --git a/spec/fixtures/files/groupe_avec_caracteres_speciaux.csv b/spec/fixtures/files/groupe_avec_caracteres_speciaux.csv
new file mode 100644
index 000000000..376e358f0
--- /dev/null
+++ b/spec/fixtures/files/groupe_avec_caracteres_speciaux.csv
@@ -0,0 +1,5 @@
+Email,Groupe
+kara@beta.gouv.fr,Auvergne-Rhône-Alpes
+camilya@beta.gouv.fr,Vendée
+philippe@beta.gouv.fr,Auvergne-Rhône-Alpes
+sim@beta.gouv.fr,Vendée
\ No newline at end of file
diff --git a/spec/models/procedure_presentation_spec.rb b/spec/models/procedure_presentation_spec.rb
index 3be47afce..9eb2bd6f7 100644
--- a/spec/models/procedure_presentation_spec.rb
+++ b/spec/models/procedure_presentation_spec.rb
@@ -45,6 +45,7 @@ describe ProcedurePresentation do
 
     context 'of filters' do
       it { expect(build(:procedure_presentation, filters: { "suivis" => [{ "table" => "user", "column" => "reset_password_token", "order" => "asc" }] })).to be_invalid }
+      it { expect(build(:procedure_presentation, filters: { "suivis" => [{ "table" => "user", "column" => "email", "value" => "A" * 200 }] })).to be_invalid }
     end
   end