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Access a legend for the map below
Source of Map: Water Resources Inventory of CT, Part 4, Southwestern Coastal River Basins,
by the U. S. Geological Survey and the CT Department of Environmental Protection, 1970.

THIS IS AN EARLY (1970) GENERALIZED MAP OF ESTIMATED AQUIFER BOUNDARIES ONLY
COMPARE IT TO LATER DATE USGS SURFICIAL MATERIALS MAP

HISTORIC BASE LINE DATA: 1980 HVCEO
REPORT ON SUGAR HOLLOW AQUIFER
Enclosed by mountains in southwest Danbury and northeast Ridgefield, this 1.2 square mile aquifer lies near the headwaters of the Saugatuck River, just below Fox Hill and Wataba Lakes. Crossed by Route 7 and by Starrs Plain Road, the area is at present lightly developed: one small light industry and a dozen scattered commercial establishments along Route 7, and low density single family homes along Starrs Plain Road.

A measure of protection has been afforded the very extensive wetlands through this aquifer (wetland controls, 2 Towns), by low density (2-3 acre) residential zoning in the adjacent 3 Towns (Danbury RA-80; Ridgefield RAAA and RAA; Redding Residential & Farm. "A"), and by a State owned reservation the Wooster Mountain State Park.

Potential land use problems, however, exist here: more than three-fourths of the primary and a large portion of the secondary recharge area has been zoned for industrial and commercial development, in both Danbury and Ridgefield. Industrial zoned area in Danbury includes both wetlands and steep mountainside.

Also due to have a major impact will be the new Route 7 Expressway, which will cross the main portion of the aquifer and consume a major section for an interchange.

Most of this aquifer is of coarse-grained texture, considered favorable for well field development, and was recommended for test drilling by the Region's engineering consultants. Extensive bedrock contact lines here suggest bedrock recharge may also occur here.

Control measures needed to prevent future degradation of water quality should at least include prohibition of industrial discharges, reduction of commercial and industrial intensities, and special design controls to prevent road salt intrusion from the new highway yet to be built.

SUGAR HOLLOW AQUIFER IN
1982 U.S. ARMY CORPS STUDY
The U.S. Army Corps of Engineers ”Housatonic River Basin Urban Study” of 1982 offered some perspective on the Sugar Hollow Aquifer. According to that study “The Sugar Hollow Aquifer has the possibility of yielding as much as half a million gallons a day for Danbury.

However, this aquifer is located in the watershed of the Saugatuck Reservoir, which is owned by the Bridgeport Hydraulic Company. Jurisdiction over aquifers is a tricky legal question, one which at present does not have many legal precedents. Some cases are now in litigation.

Consequently, in order for the Sugar Hollow Aquifer to be tapped for Danbury use, this legal ownership question would have to be answered. A wellfield, pump station and transmission main would be required to transport the water to Danbury. The total cost of this plan is estimated to be $372.000.”

Also from the Corps study: “If properly developed this aquifer could yield up to 0.5 million gallons per day. A wellfield and pump station along with a 1300 foot long, 6 inch transmission main would transport water to the Danbury system.”

SUGAR HOLLOW AQUIFER
IN 1984 USGS STUDY
A document entitled "CT DEP 1984 Ct Water Resources Bulletin 33B, Groundwater Availability of Selected Stratified-Drift Deposits in Southwestern Connecticut", by Martha Weaver of USGS, addresses the Sugar Hollow Aquifer.

The report found that “The most transmissive regions are found in the center of this long, narrow valley, where the stratified-drift material is both coarse-grained and thick.”

The potential for public water supply withdrawal was modeled by a computer in the report, where it states that “Five hypothetical pumping wells were evenly distributed in the thickest most transmissive portions of the model area . . . The estimated combined sustained daily pumpage these wells can produce was found to be 1,100,000 gallons per day.”

Continuing, “The total recharge available to the model area through natural and induced recharge was calculated to be 1,000,000 gallons per day. This small volume of water available per day through recharge results from a relatively small drainage basin area. . .

The available recharge is less than the combined estimated long term pumpage calculated, and therefore the available recharge is the limiting condition in analyzing the amount of water available from the aquifer. . .greater pumpage rates will result in water levels declining too low and stream beds drying.”

EXCERPT ON THE SUGAR HOLLOW AQUIFER
FROM A 1995 RIDGEFIELD PZC CONSULTANT’S STUDY
There have been several water supply investigations at a parcel adjacent to a pond, located approximately one-half mile north of the intersection of Routes 7 and 35, to the east of Route 7. Investigations have been performed by the Ridgefield Water Supply Company and private individuals.

Three USGS test holes were drilled in the portion of the aquifer in the Town of Danbury. Two well completion reports are on file at the Health Department for the portion of the aquifer within the Town of Ridgefield. Additional test hole and well data are also available for the portion within the Town of Ridgefield from reports produced by S. B. Church and Geraghty & Miller for the Ridgefield Water Supply Company.

The USGS test holes indicate that the stratified-drift thickness is at least 84 feet in the portion of the aquifer within the Town of Danbury. The area east of Route 7 is mapped with thicknesses of greater than 30 feet but less than 60 feet in the portion within the Town of Ridgefield.

Well completion reports for the portion within the Town of Ridgefield and for the area east of Route 7, based on the S. B. Church and Geraghty & Miller test holes, indicate the stratified drift is up to 37 feet thick, consistent with the USGS mapping. The aquifer is composed of interbedded fine to coarse sand, gravel, silt and clay.

Note that very little of the Sugar Hollow aquifer is within the Town of Ridgefield. The aquifer portions within and near Ridgefield are beneath tributaries to the Saugatuck River. Unfortunately, although the aquifer material is good, the watershed areas within Ridgefield are very limited. Watershed area is important because it is the source of recharge to the aquifer.

The Sugar Hollow aquifer has been previously considered a significant aquifer, capable of upwards of 300 gpm (gallons per minute) to wells in the portion east of Route 7 within Ridgefield. However, the limited watershed area within Ridgefield does not indicate these yields would be sustainable.

No data exist for a significant portion of the aquifer in the vicinity of Bennett Ponds where the USGS mapped the aquifer thickness as greater than 10 feet but less than 30 feet.

The 7 day, 10 year low flow is estimated to be between 0. 04 and 0. 06 million gallons per day for the pond area east of Route 7 and between 0. 04 and 0. I 1 million gallons per day for the Bennett Ponds area. The average low flow for the two areas is estimated to be about 0.13 and 0.18 million gallons per day, respectively.

No analysis of water samples for organic compounds has been performed. Analysis for major ionic constituents are on file at the Health Department. LBG's search of the DEP's records revealed the investigation of one incident involving the illegal storage of drums with unknown contents at a property overlying the aquifer.

CT DEP 2002 COMMENT ON
SUGAR HOLLOW AQUIFER
As part of the Connecticut DOT’s reconstruction of Route 7 in Danbury and Ridgefield, a wetland permit was requested from the Connecticut DEP. The DEP’s proposed final decision of September 10, 2002 included the following about the Sugar Hollow Aquifer:

"The Sugar Hollow Aquifer is identified by the State of Connecticut Department of Health and Addiction Services, and the Ridgefield Water Supply Company as having a potential for development of future water supplies along this portion of the study area.

The Ridgefield Water Supply Company (now Bridgeport Hydraulic Company) is presently looking for a supply of water for the northern portion of Ridgefield. One of several alternate sites presently being investigated is located east of U.S. Route 7 in Ridgefield.

The proposed storm drainage design for this project has been coordinated closely with the Ridgefield Water Company. As requested by the Water Company, we have eliminated outlets, separated roadway runoff from offsite water, and redirected roadway storm drainage away from a potential well site. This will improve the water quality in the area.

The Atlas of the Public Water Supply Sources & Drainage Basins of Connecticut (1982) lists two well sites as occurring in the vicinity of the study area, both of these utilize the water resources of the Sugar Hollow Aquifer. Two wells belonging to the Lake Waubeeka Property Owners Association..... and a small, private well that served Danridge Manor Apartments (removed)."