diff --git a/src/directed/edmonds_karp.rs b/src/directed/edmonds_karp.rs
index c7c137ce..9d482d97 100644
--- a/src/directed/edmonds_karp.rs
+++ b/src/directed/edmonds_karp.rs
@@ -364,8 +364,6 @@ pub struct SparseCapacity<C> {
     residuals: BTreeMap<usize, BTreeMap<usize, C>>,
 }
 
-unsafe impl<C: Send> Send for SparseCapacity<C> {}
-
 impl<C: Copy + Eq + Zero + Signed + Bounded + Ord> SparseCapacity<C> {
     fn set_value(data: &mut BTreeMap<usize, BTreeMap<usize, C>>, from: usize, to: usize, value: C) {
         let to_remove = {
@@ -498,8 +496,6 @@ pub struct DenseCapacity<C> {
     flows: Matrix<C>,
 }
 
-unsafe impl<C: Send> Send for DenseCapacity<C> {}
-
 impl<C: Copy + Zero + Signed + Ord + Bounded> EdmondsKarp<C> for DenseCapacity<C> {
     fn new(size: usize, source: usize, sink: usize) -> Self {
         assert!(source < size, "source is greater or equal than size");