One long walk a day for black lab?

[Barefoot789]

We have a 16 month old black lab who currently receives between an hour and 20 mins and an hour and 45 mins exercise a day.
At the moment it's in the form of one short walk on the lead and then a longer run around off lead with other dogs, chasing a ball etc.
He also gets out in the garden, gets played with a lot with a house full of kids.
Come September I'll no longer be able to walk him on the school run as one of mine is starting nursery which involves actually taking her in, and the dog doesn't like being tied up and left.
So I was wondering, does anyone think it would be ok to give him one long session of exercise around midday, with other periods of play in the garden?
DH is often away so I can't rely on him to do an evening walk, meaning I have to take the children out with me after tea to walk him again.
Or I try and fit in a long and short walk within the school day timeframe, which is doable but one big walk would be easier.
Please be kind! I'm kind of scared of your responses!

Our dogs get one long walk off lead a day and are absolutely fine on it.

Sounds fine to me and if you manage any extra walks then that's a bonus .

I suppose it's a case of trying it and seeing how he gets on.
Since summer holidays began I've been pushing his first walk back and making that his long walk and he's been ok with it.
But taking him out again is a bit of a drag! I've just taken him out now with toddler in tow and it took ages as she insisted in walking and looking at every single leaf and stick on the way!!
I think we'll see how he adjusts to it then.

We have a 13 month Black lab and i do a one hour walk straight after school run and then a half hour round the block walk at about 2:00 ush or just before picking kids up as its just easier than dragging kids too and it means I dont suffer the guilt of only taking him out once. However during the school hols I have been occasionally doing one longer walk later in the day. My view is that to some extent they do have to fit in. I also do leave him outside a shop with my eldest if I can see them if it means he gets an extra short walk without the kids realising we are walking the dog AGAIN iyswim !!

Meant to add I am in same position that majority of walking is down to me as Husband away alot so cant do a walk after 7:30 ish when kids getting ready for bed.

ignore my thread about him crapping overnight

our lab of same age has one big walk (at least an hour) and then normally a short walk in the afternoon. We live in a city and our garden isn't huge. But if it was bigger I'd feel OK with some games hiding stuff etc to mentally tire him out a bit more. We do it a bit but he doesn't cover much ground when looking vs us doing it in the park! xx

Yes babyblackbird that sort of timing was my original plan, if he's not ok on one long walk I'll go for that sort of arrangement.
Thanks everyone, it's made me think it's at least worth a shot.
He's always been so good in the house, and I'm sure it's because he's well exercised, so I'd hate to jeopardise that.
LittleMilla I'll steer clear of your thread then!!