There had been a ''noticeable decrease'' in the number of drink drivers apprehended in the South since lower levels were introduced, police say.
On December 1, the breath-alcohol level for over-20s was slashed from 400mcg of alcohol per litre of breath to 250mcg.
Southern District police have reported motorists are being ''much more cautious and refraining from having anything to drink prior to driving, which is pleasing'', acting road policing manager Senior Sergeant Geoff Sutherland said.
''Police have seen a notable decrease in the number of drink-drivers being apprehended.''
Those officers, who stopped thousands of vehicles in Otago and Southland each month, also noted a reduction in the number of drink-drivers under-20.
The alcohol level for that group is now zero.
This follows a downward trend in the Southern District in 2013-14, with 1347 drink-drivers apprehended, compared with 1925 in 2008-09.
It appeared drivers were being more responsible, Snr Sgt Sutherland said. Those deciding to drink alcohol were making plans for getting home that did not involve driving, he said.
Figures released to the Otago Daily Times show a 41-year-old Oamaru man has the dubious distinction of having the district's highest breath-alcohol level since 2010-11, recording 1662mcg.
Dr Leo Schep, a toxicologist with the National Poisons Centre, in Dunedin, estimated that for an 85kg man to reach that limit, he would have to drink 18.7 cans of 4% beer.
A 70kg woman - to reach the top female level of 1623mcg held by a 46-year-old Invercargill woman - would need to consume a dozen of the same strength beer to reach that level.
Snr Sgt Sutherland said few people returned such high readings, and those who did often had a serious and problematic relationship with alcohol.
''They pose a real risk to themselves and others, as does anyone who drinks and drives. Some of those drivers would be recidivist offenders and their relationship with alcohol was likely to have a negative impact in many ways, including the potential to cause significant harm on our roads.
''It is an awful reality that there are still people in our communities who make the bad decision to get behind the wheel after drinking and put other people's lives at risk.''
He urged anyone who saw someone about to drive after drinking alcohol to ''do the right thing for your community and have a conversation with them about how they can get home safely''.
''People who consume alcohol and then drive create a deadly mix and are more likely to cause harm on our roads.
That can result in death or serious injury to themselves and others, often friends and family.''
Our worst drink-drivers
*Based on the five highest readings (micrograms of alcohol per litre of breath) supplied by 14 police stations in Otago and Southland in the four years ending 2013-14.
*Highest reading: 1662 mcg/litre (41-year-old male, Oamaru)
*Oldest offender: 68-year-old male (1640 mcg/litre, Alexandra)
*Youngest offender: 17-year-old male (1037 mcg/litre, Alexandra)
*Males: 69% (48 drivers)
*Females: 31% (22 drivers)
SOURCE: NZ POLICE
| Alexandra | Balclutha | ||||
| Alcohol level | Age | Gender | Alcohol level | Age | Gender |
| 1640 | 61 | M | 1242 | 24 | M |
| 1480 | 68 | M | 1178 | 41 | F |
| 1086 | 21 | M | 1174 | 35 | M |
| 1083 | 62 | M | 1131 | 41 | F |
| 1037 | 17 | M | 1112 | 42 | M |
| Dunedin Central | Dunedin North | ||||
| Alcohol level | Age | Gender | Alcohol level | Age | Gender |
| 1656 | 30 | M | 1419 | 42 | F |
| 1619 | 28 | M | 1389 | 51 | F |
| 1486 | 28 | F | 1294 | 54 | M |
| 1386 | 27 | M | 1253 | 21 | M |
| 1323 | 61 | M | 1237 | 29 | F |
| Dunedin South | Gore | ||||
| Alcohol level | Age | Gender | Alcohol level | Age | Gender |
| 1516 | 37 | M | 1260 | 24 | F |
| 1402 | 32 | F | 1243 | 25 | M |
| 1367 | 53 | M | 1234 | 21 | M |
| 1361 | 30 | F | 1175 | 24 | M |
| 1322 | 46 | F | 1087 | 37 | F |
| Invercargill | Milton | ||||
| Alcohol level | Age | Gender | Alcohol level | Age | Gender |
| 1623 | 46 | F | 1372 | 21 | F |
| 1499 | 31 | F | 1149 | 29 | M |
| 1404 | 37 | F | 1140 | 26 | M |
| 1366 | 45 | M | 1123 | 56 | M |
| 1296 | 27 | F | 1071 | 43 | M |
| Mosgiel | Oamaru | ||||
| Alcohol level | Age | Gender | Alcohol level | Age | Gender |
| 1344 | 46 | F | 1662 | 41 | M |
| 1284 | 46 | F | 1604 | 41 | M |
| 1170 | 41 | F | 1303 | 52 | M |
| 1132 | 45 | M | 1251 | 20 | F |
| 1041 | 43 | M | 1226 | 28 | M |
| Queenstown | Te Anau | ||||
| Alcohol level | Age | Gender | Alcohol level | Age | Gender |
| 1540 | 40 | M | 1322 | 21 | M |
| 1398 | 36 | F | 1296 | 53 | F |
| 1372 | 23 | M | 1230 | 31 | M |
| 1283 | 23 | M | 1146 | 19 | M |
| 1240 | 36 | M | 1098 | 22 | M |
| Wanaka | Winton | ||||
| Alcohol level | Age | Gender | Alcohol level | Age | Gender |
| 1360 | 33 | M | 1259 | 54 | M |
| 1338 | 53 | M | 1119 | 28 | M |
| 1281 | 23 | M | 1105 | 44 | M |
| 1264 | 20 | M | 977 | 36 | M |
| 1232 | 24 | M | 976 | 34 | M |