A first violation carries a $500 fine for most customers, rising to as much as $1,000 for repeat violations. Fines for multifamily customers start at $1,000. Denver Water said it mailed every customer a postcard warning about the rules before citations began.

The utility’s Greg Fisher said enforcement became more straightforward after the restrictions took effect because spray irrigation was prohibited altogether. “If we saw spray irrigation at all, we could assess a violation,” he said.

The enforcement comes as Denver Water reports a sharp drop in use: customers reduced consumption by 33% during the first 18 days of the restrictions, saving billions of gallons, according to the utility. Through September, it had received more than 7,500 reports of water waste and issued more than 2,000 formal warnings.

Residents are divided over the penalties. Denver resident Mads Delgado criticized what they described as unequal treatment of residents and large businesses, saying fines risk turning neighbors against one another. Jeff Huffman said the penalties were justified after a dry winter and summer, adding that the region needs to conserve water.

Denver Water expects its reservoirs to be about 60% full by next spring, well short of its 85% target. Fisher said the drought will persist until the region gets a strong snow year, and the utility is urging customers to keep conserving water.