Collin Smith had to have his leg amputated after dog poo on a rugby pitch got into a wound and caused a serious infection.
His local council is now one of 12 in Wales using Public Spaces Protection Orders (PSPOs) to fine dog owners who do not pick up after their pets.
Rhondda Cynon Taf council has issued the most fines so far - £22,000 worth in the last 10 months.
Mr Smith, 53, from Miskin, a dog owner himself, welcomed the move.
He said: "In November 1979 I was playing rugby for the first XV for Tonyrefail Comprehensive when I received a compound fracture - tibia and fibula - where the bone came out and pierced the skin.
"I was taken to hospital, my leg set in plaster and within 24 hours they discovered I had an infection.
"It turned out to be an infection caused by animal faeces, which spread… they had to do a through-knee amputation and the result of that a prosthetic leg."
Mr Smith said while medical advances now mean amputation is less likely for someone who catches an infection, there were still other risks - such as toxocariasis.
"Today there's a lot of conscientious people, but obviously there are a lot of people that are just so irresponsible," he said.
"I'm a dog owner and we walk our dog in a fit and proper place where he can do his business which is not in and around children.
"That residue seeps into the ground, it disappears and it's a hidden accident waiting to happen."
PSPOs allow councils to introduce extra powers for police or other specially designated enforcement officers, to stop, question and fine people for anti-social behaviour.
In this context, they are used in addition to existing laws on dog fouling and other anti-social behaviour, but can often make it easier to successfully fine or prosecute individuals because it sets out a series of explicitly defined rules.
In Rhondda Cynon Taf, the rules include keeping a dog on a lead in designated areas, a ban on dogs on marked sports pitches, and owners having bags in their possession to clean up after a dog.
Failure to abide by the rules results in a £100 fine.
Nigel Wheeler, the council's director of highways and street care, said four dedicated enforcement officers wear body worn video cameras to record conversations when issuing fines.
He said: "The £20,000 in fines covers some of the costs of the wardens and we subsidise the rest.
"We've based the enforcement team on what the public wanted - the public told us it was a big issue for them, and we tackled that.
"I don't think people really take heed of warnings - we've done that in the past - you've got to think of the safety of the young people on the pitches, people were letting their dogs roam and foul."
He added that in the last two months 13 people who did not pay their £100 fixed penalty notices were taken to court and ordered to pay fines totalling more than £5,000.
What are other councils doing?
Other councils using PSPOs to target dog fouling are: Blaenau Gwent, Caerphilly, Carmarthenshire, Conwy, Denbighshire, Flintshire, Gwynedd, Neath Port Talbot, Newport, Torfaen and Wrexham.
Bridgend, Cardiff and the Vale of Glamorgan said they were currently consulting on bringing one in.
Swansea, Powys, Pembrokeshire, Isle of Anglesey, Monmouthshire and Ceredigion do not have a PSPO in place for dog fouling, but retain powers to fine under other by-laws.
Merthyr Tydfil did not respond to our request for information.
Local authorities with PSPOs in place tended to issue more fixed penalty notices.