Tiered water rates

The city's new tiered water rates are going to take effect pretty soon, and there was some discussion on my neighborhood listserv this morning over how they work.

From the city website:

Service charges for both water and sewer will also rise. These "base" charges cover the cost of meter reading and billing and other fixed costs of the water and sewer operations. For customers with 5/8 and 1 inch meters (primarily residential customers), service charges will increase from $2.58 per month to $5.11 per month for water and from $3.19 a month to $5.71 for sewer services. Customers living outside of the city limits will continue to pay twice as much as customers living inside city limits.

The new rate tiers reflect what the City charges for a "unit" of water as shown on bills, which is 100 cubic feet, or 748 gallons. Most residential customers fall in the Tier 3 range, using about eight units over a two-month billing period. A customer using four units over the two-month period will be charged at the Tier 1 rate and see about an $11 increase in their total bill. A customer using 12 units over the bi-monthly period would be charged at the Tier 1 rate for the first two units of each month, at the Tier 2 rate for the next three units of each month and at the Tier 3 rate for the remaining unit used each month. This customer's bi-monthly bill would increase about $13.

Doing our own math, we find that for a customer who is using exactly 15 units per month, the base rate rises exactly the same (from $11.54 per billing cycle to $21.64 per billing cycle) and the sewer use charge also remains the same at $98.40 per 2 month billing cycle. The water use charge will rise from $46.80 per billing cycle to $65.44 per billing cycle for a new total of $185.48. That's up a grand total of $28.70 per billing cycle, from $156.78, or $14.35 per month. Compared with a $11 per cycle increase (or $5.50/month) for the most conservation minded customers*. So water wasters are going to be nicked just under 9 bucks a month more than water misers.

I'll leave it as an exercise for the reader to determine whether this is sufficient to change behavior.

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* To be fair, the tiered rates do not take into consideration the number of people living in a household. So, per person use could be the same for a 1 person household and a 6 person household, but the larger one will end up paying the surcharge. Maybe the difficulty of accounting for the difference in household size factored into the decision to keep the tiers relatively close to each other in price.