Can a Swale (0.5%) with an Underdrain (0.0%) Eventually Outlet Directly into the Swale?

Does this make sense: I have infiltration trenches with perforated underdrains underneath and then cobra head style upwards to discharge into a 0.5% adjacent swale that also has a perforated underdrain. The swale is there for any overflow once max ponding depth is reached, however, the cobra head style underdrain cannot discharge onto the swale surface, only the underdrain itself (with 1 foot of cover underneath), otherwise, the top of the cobra head will be higher than the max ponding limit. My idea is to have the underdrain under the swale start as 0.5% but then transition to 0.0% and as a non-perforated underdrain. The underdrain in the swale can't terminate at the end of the swale because it'd be lower than the culver the swale is discharging to. Is it possible to have the 0.0% underdrain daylight directly into the 0.5% swale, and then have notes added for the contractor to not damage the pipe with the decreasing cover as it daylights with the rip rap that will be in the swale? Is it practical or make any sense? I can't find other solutions