I chaired a public hearing of the City Council’s Health and Environment Committee on September 28 to discuss the impact of the severe drought conditions and what strategies we are implementing to manage our supply and encourage conservation. The hearing was televised and recorded for online viewing. Sam Corda, managing director of the Water Department, gave a very information slide presentation that is part of the video. You can watch it here.
The most important thing to know is that while the water supply in Cambridge’s own reservoir system is at 10-year record low levels (we have a 35-40 day-supply left), we have the ability to go on MWRA water and will do so in early October. This will have a budget impact because MWRA’s rate is twice the city’s. It is estimated that buying MWRA water could add as much as $10.8M to our water costs in FY17 (based on $1.2M/month for 9 months if we were to start using it in October and continue through the end of June 2017). Since FY17 water rates were set earlier this year without accounting for the extra cost of using MWRA water, we would have to tap into both our water reserve fund and our free cash reserve to cover the gap without imposing a mid-year rate increase. Finance Director Louis De Pasquale said that the current plan is to borrow $4M form the water fund (leaving about $6M in the fund) and to take about $6.8M from free cash, where we have over $180M. If a rate increase were necessary in the future it’s important to know that water only accounts for about 27-28% of the average bill, and sewer represents the rest; sewer charges are not impacted by going on MWRA water.
Here is a summary of what else we learned about the drought situation:
- We would need 9-12″ of rain over a 4-week period to get our reservoir supply back to normal levels. This is unlikely outside of a very severe storm. Normally the “recharge cycle” to replenish levels starts in September, but this fall has continued very dry after an unusually dry winter, spring and summer. We started 2016 with a deficit, so the drought is now entering its second year. When fully charged, our supply covers about 8 months of consumption with no rain.
- The water level at Fresh Pond is always kept full at 15-16′ (1.5B gallons) to protect the system’s quality, and the majority of our supply comes from our reservoir sub-basins in Waltham (Hobbs Brook) and Lincoln (Stony Brook). If you go and look at those you will see parched dry earth in places. We cannot let the water supply drain all the way down without damaging our pipes. Our capacity is at about 25-30% now versus about 90% last spring.
- Despite considerable growth in our residential and commercial property base over the last several decades, the city’s total daily water demand is down significantly (to 14M gallons/day from 24M at the 1971 peak), and our per capita daily usage rate (49 gallons/person/day) is well below the state goal (65). However our unaccounted-for water use (12.2%) is slightly above the state’s goal (10%), so we still have a work to do in metering all usage and stopping leaks. Automatic water meters with leak detectors have helped us a lot since they were installed in 2005.
- We don’t have the same ability to significantly reduce demand through use restrictions as suburban towns do since we don’t have large lawns that consume a lot of water for irrigation. Our DPW has started to cut back by half its irrigation of playing fields and parks, but even when we stop watering entirely, as we probably will next month, it only saves us the equivalent of a couple of days worth of water. We have continued to water our younger public trees every 5-7 days, but have curtailed planting new trees this fall. We have money in this year’s budget and will ask for it in next 4 years’ budgets for remote control shut-off valves so that irrigation can be stopped when it rains.
- The 22 water play features in tot lots are big water hogs. They not only consume a lot of water (they do not recycle it like decorative fountains because it would be unsanitary), but they break a lot because they get clogged with sand. Families love them but they are wasteful and expensive to operate. We water hanging flower baskets in commercial areas 3 times a week and the amount of water used is negligible, but it can appear wasteful when we are asking people to conserve. Someone suggested planting drought-resistant grasses and perennials in the beds in front of City Hall instead of tender annuals, which need regular watering and frequent replacement.
- The Water Dept is developing a water use restriction plan to put in place before next spring’s watering season starts, and will use multiple communication channels to get the word out to residents and businesses to conserve.
- The public health impact of droughts include a higher risk of dehydration (elders and children are especially vulnerable), more allergens in the air, increases in injuries on hard compacted playing fields, and severe stress on trees that could threaten our ability to maintain and increase the shade canopy over the long term. Our climate change study has predicted that we will have many more days over 90 degrees and much greater variations in precipitation, meaning that periods of drought will become the new normal. Also mosquitos actually thrive in droughts because the standing water in which they breed becomes more concentrated and richer in proteins. Drought can also contribute to algae blooms in our rivers because when it rains the runoff doesn’t get absorbed as easily in the dry ground. Leaf blowers used on very dry planting beds and lawns are more apt to spread dust and allergens.