Cross posted from Davis Enterprise.

My last column made the point that energy and water are inextricably linked, and efforts to reduce water consumption also reduce energy usage and greenhouse gas production. This is a follow-up to that column.

The city-sponsored community forum I talked about in the last column featured a lot of useful information. If another is scheduled, it’s well worth your time. Meanwhile, here are a few items from the presentations. I’m using my August through September 2011 water bill for the numbers below.

The water bill: First, the “water bill” is actually a composite that includes charges for storm and sanitary sewers as well as a “public service tax” and a “public safety charge.” The water portion of my bill was $68.50 (about 28 percent of the total bill). I’m sure everyone already knows this, but the bill comes once every two months. I think in terms of monthly expenses, so, dividing it in half means I’m paying $34.25 a month (at least for those two months) for water.

Second, the water rate is broken down into two parts. One, the “base charge,” is for infrastructure, is the same every month (mine is $23), and is independent of how much water is used. Two, for actual water used there are two price tiers. The first goes up to 36 ccf (hundred cubic feet) at $1.50 per ccf; the second is for anything over 36 ccf and is charged at $1.90 per ccf.

The whole ccf thing is confusing — it should be in gallons — but that is how our meters read the amount of water we use. Since almost every discussion of how to save water is couched in terms of “if you do measure X you’ll save Y gallons” it’s useful to know that one ccf equals 748 (round off to 750) gallons.

Doing the math from the information above indicates the current charge per gallon (up to 36 ccf) is about two-tenths of one cent (considerably cheaper than bottled water). So, 50 gallons of water costs a penny.

The average Davis resident uses about 150 gallons of water each day.

Where water is used: The average Davis resident uses about 150 gallons of water each day. The water conservation video on the city website says the average household uses about 500 gallons per day. According to a city of Davis study, more than half of this is for landscaping and other outdoor purposes.

Next in line are toilets and system leaks at about 10 percent each. Apparently, leaks in the system cost me about $3.50 a month. Showers account for about 9 percent, and clothes washers and faucets 7 percent each.

Conserving water: Clearly, the biggest water use is for landscaping, and the biggest water and energy and money savings are found by reducing water used for this purpose, either by watering less (apparently most of us over-water), watering smarter (design the watering system to give each plant the amount of water it needs) or/and knowing when to water (when it’s not windy or hot).

The biggest water and energy and money savings are found by reducing water used for landscaping

The city website has information on efficient lawn watering, at Accepting the 500 gallons per day per household number means each home is using about 180,000 gallons a year, of which about 100,000 gallons is for watering the lawn and other outdoor uses.

It was stated at the forum that in most cases it’s possible, through conservation measures, to reduce lawn watering by as much as 50,000 gallons over a year’s time, for a savings of approximately $100.

There are also lots of opportunities for conserving water indoors. The statistics above indicate that toilets account for 10 percent of our household water usage. The city has a rebate program  that will give a credit on the utility bill of up to $125 (limit two toilets) for residents who upgrade to a 1.28 gallons-per-flush EPA “Water Sense” toilet. Certain conditions apply (don’t they always?).

A similar rebate is available for efficient washing machines is at

Finding and fixing leaks: Some leaks are easy to find and fix and can save lots of water. Consider the city’s statistics: a dripping faucet can waste nearly 20,000 gallons ($40) a year, a running toilet 125,000 gallons ($250) per year, and a leaky pipe more than 500,000 gallons ($1,000) per year. Some leaks are harder to find, especially leaks in an irrigation system.

The really good news is that the city has a free leak detection program. If you think you have a leak (i.e., your water bill is too high) call the Public Works Department at (530) 757-5686 and request a leak check and water analysis. The city is also proactive on this; they monitor water usage on residential customers and if they notice a spike that seems out of the ordinary they will alert the property owner of a possible problem.

Already in California we are “over-subscribed,” with more rights to water having been allocated than there is reliable supply. Here, as in the rest of the world today as we pass the 7 billion mark for human population, conserving water will take on more and more importance.

— John Mott-Smith is a resident of Davis and a member of the core group of the Cool Davis Initiative. This column is published twice a month. Send comments to johnmottsmith AT