Monomoy Lens Water Departments Issuing Mandatory Bans

By: William F. Galvin

Brewster Water Department Superintendent Paul Anderson and Harwich Water and Wastewater Superintendent Dan Pelletier examine a map of the Monomoy Lens at the Harwich Water Department last Friday. WILLIAM F. GALVIN PHOTO

HARWICH —Mandatory water bans have been put in place in Harwich, Brewster, Dennis, and Orleans, four of five towns which extract public water supply from the Monomoy Lens aquifer.

Chatham's water and sewer advisory committee is scheduled to discuss a ban today (Thursday, May 13).

The ban allows watering on odd and even days, based on house number and calendar date, between 4 a.m. and 8 a.m. and 5 p.m. to 9 p.m to minimize evaporation. Water superintendents recommend that homeowners don't water on days when it is not necessary.

The commonwealth’s Drought Management Task Force has declared level-1 mild drought status for Cape Cod, but water superintendents in the five towns agree the United States Geological Survey monitoring well for the Monomoy Lens, located in Brewster, shows that conditions are much more severe.

“According to our monitoring well, it’s much more severe than a mild drought,” Brewster Water Department Superintendent Paul Anderson said last Friday.

The situation has to be serious to get water superintendents from all of the Monomoy Lens communities together to discuss a response, Anderson said.

“We all have a straw in the same glass,” Anderson said.

“We felt it is important because the aquifer is in pretty serious condition,” added Harwich Water and Wastewater Superintendent Daniel Pelletier. “It’s important for the towns to be consistent.”

The towns of Harwich, Brewster and Dennis have taken steps to implement a mandatory watering restriction schedule based on odd and even street numbers. In the recent past the towns have put in place voluntary odd and even irrigation restrictions, but it’s been a while since a mandatory ban has been implemented. In Orleans, exterior watering will be allowed only twice a week.

Pelletier said his records show the last time a mandatory restriction was put in place in Harwich was 2003. Anderson said he has been working in Brewster since 2009 and does not remember implementing such a restriction.

Anderson said the state Department of Environmental Protection is usually the organization that is trying to push the Monomoy Lens communities to implement mandatory restrictions. The towns in the lens usually push back, but that is not the case now because the water departments recognize the severity of the situation.

The groundwater level measured at the USGS monitoring well located at Nickerson State Park in Brewster shows the aquifer at about 31.5 feet below land surface, down more than two-and-a-half feet from this time last year. That is the depth of the average annual low point for the water level. Pelletier said his department has examined the 14 wells in Harwich and they are showing drops in the aquifer from 1.2 to 2.8 feet.

“We’re starting at a low level,” Anderson said.

A year ago the groundwater levels were favorable, Pelletier said.

“We do not get to save water from last year. It heads to the ocean at a foot a day,” Anderson said.

The water superintendents said winter snow and rain are the major contributors to replenishing the aquifer, but with little snow and rain this winter, the groundwater table is lower than usual. Anderson said the rain in the warmer season does not contribute much because it is either taken up by vegetative growth or evaporates in the heat of the day.

More than half of the water generated in a year by the town is consumed during that warm weather period, Pelletier said. The average from 2008 to 2018 shows 52 percent of the water pumped each year is consumed between June and September. The majority of it is used for watering lawns and gardens.

With the summer season approaching and predictions for a strong rental season, major water demand is expected. Pelletier said he does not know if the increased year-round population due to the pandemic impacted water use increases, but his department’s pumping level was up 20 percent in the last year. His pumps at times have run 20 hours per day.

The ban is in effect right now, Anderson said, and both he and Pelletier said their towns have in place provisions that allow fines for violations. Their goal, they said, is to get homeowners to comply, not to issue fines.