What I remember about the Indian nets is that they are supposed to leave room for boats to navigate around the nets.
I recall a few years ago seeing a net from bank to bank (on a local river)and I questioned the Indian about leaving room for navigation, He mumbled something about the tide being out and when he laid the net he left room for navigation.
He then went into a fit talking about how a guy with a prop on tore up one of his nets and how much they cost etc.
Didn't really feel sorry for him at all, I figured if he had any sense at all he would have learned not to block off the whole river.
Ramprat