The Town of Bayfield will have significant water system needs over the next 20 years, according to an engineering study being considered by the town board.
Town Manager Chris La May presented an overview of the study to trustees on Feb. 17. "We're ready to take it to the planning commission to include in the comprehensive plan," he said.
Using a 3.2 percent growth factor, the study projects the town population will be around 6,000 by 2035. According to the 2010 Census, it was then around 2,300. The study estimated population at just over 2,500 at the end of 2012.
The study looked at average and maximum daily demand in winter and summer, along with per capita daily demand, to project future system needs. Maximum daily demand over the past several years has ranged from .82 million gallons per day to .94 mgd during summer yard watering season. Demand has gone down some with alternate day watering restrictions.
The study puts average per capita daily water use at 160 gallons, with a summer high of 216 because of yard watering. The town has distribution losses of 37 percent that need to be investigated and fixed, the study says.
The current water treatment plant rated capacity is 1.5 million gallons per day, La May said, but because of water losses the real capacity could be more like 1.3 mgd.
The town is starting into a plant capacity expansion project as a joint venture with the La Plata/ Archuleta Water District (LAPLAWD). It will expand from 1.5 mgd to 2.5 mgd, with .75 mgd of the new capacity for LAPLAWD, and with design capacity for a future expansion to 3.5 mgd.
La May said the pre-bid conference with interested contractors was set for Feb. 18.
The town's water rights and the infrastructure to get water from the river to the treatment plant storage reservoir also need attention, the study says. So does the distribution system for treated water.
"We knew some of this information when we prepared the (water) rates last year," La May said.
The town has early priority direct flow rights in the Pine River and storage water in Vallecito for times when the town's direct flow rights go out of priority.
The study's executive summary says, "The most pressing area that presents a potential future capacity limitation is available municipal water rights. User demand is projected to overcome the currently available municipal rights within the next five years. Converting the remaining 1.869 cubic feet per second irrigation right on the Los Pinos Ditch is believed to be the best first step to increase municipal raw water supply rights."
Most of the town's water comes via the Priority 4 Los Pinos Ditch. The town has rights to 2.869 cfs, but only 1.0 cfs of that has been converted from irrigation to municipal use. The ditch company reduces the actual municipal right to .85 cfs to account for water loss in the ditch.
The town also has rights via the P-12 Schroder Ditch, a total 1.737 cfs with .785 of that converted to municipal use.
The town has been working to convert the irrigation rights in Water Court, always a slow process. Also a high priority is expanding the capacity of the town's pump station in the river that gets all the Schroder water and some of the Los Pinos water to the treatment plant.
Public Works Director Ron Saba said, "We're probably good for at least 15 years with the shares we have. I feel pretty comfortable with the size of the town and the rights we have." With all irrigation rights converted to municipal use, he estimated the town could probably double in size.
However, the study says the town's current municipal rights should be able to meet maximum daily demand (MDD) through this year; and if all the town's Los Pinos ditch rights are converted to municipal, "that would provide a raw water supply of almost 1.85 mgd (not reduced by the Ditch Company imposed 10 to 20 percent loss). This quantity is projected to be sufficient to meet MDD usage rates through year 2020."
If all the Schroder rights are also converted to municipal, that should be sufficient in non-drought conditions through 2028, but the town is projected to need additional rights before then, the study says.
It projects raw water demand at about 2.2 mgd in 2030 to meet maximum daily demand. On March 3, trustees approved a per unit cash in lieu fee for future development on land that has no water rights to convey to the town.
The joint treatment plant expansion with LAPAWD will bring the town's share of capacity to 1.75 mgd, which should be adequate through 2028, the study says. It recommends planning for another expansion before then.
The town has around 15.5 miles of distribution lines and four storage tanks with total capacity of 1.75 million gallons at the north edge of town. Water from the treatment plant must be pumped up to those.
The study lists sections of transmission line that are undersized for peak demand, or just old, that should be replaced. It cites the 6-inch asbestos-concrete line along Mountain View Drive that gets water south of Highway 160.
"A failure within this section could be disastrous to the overall distribution system," the study says, although it doesn't list a time frame for replacement.
By 2025, the 10-inch line that leaves the water plant and the 10-inch line going up to the water tanks will need to be replaced with larger lines, the study says.
