diff --git a/R/RunModel_LLR.R b/R/RunModel_LLR.R
index 63bd8b3ab3e01344e671dea56ed01ac95cf03066..5ab9884fdd5f4bf5bcc75d53434193dbb96e7d75 100644
--- a/R/RunModel_LLR.R
+++ b/R/RunModel_LLR.R
@@ -70,9 +70,11 @@ RunModel_LLR <- function(InputsModel, RunOptions, Param, QcontribDown) {
 
   ## propagation time from upstream meshes to outlet
   PT <- floor(InputsModel$LengthHydro * 1e3 / TParam / RunOptions$FeatFUN_MOD$TimeStep)
-  PK <- sqrt(InputsModel$LengthHydro/max(InputsModel$LengthHydro)) * KParam
+  PK <- ifelse(InputsModel$LengthHydro == 0,
+               0,
+               sqrt(InputsModel$LengthHydro/max(InputsModel$LengthHydro)) * KParam)
 
-  C0 <- exp(-1/PK)
+  C0 <- ifelse(PK ==0, 0, exp(-1/PK))
   C1 <- ((PK/1) * (1-C0))-C0
   C2 <- 1 - (PK/1) * (1-C0)
   ## Lag model computation