Floodplain Management

The City is working on ways to improve and increase its circulation of and accessibility to information that pertains to the floodplain, in an effort to better educate and assist its citizens about developing and living in the floodplain. Please take the time to read the information below, and if you have further questions, or would like additional information, a variety of contact information is available on the Resources page.

The City of Ephrata is located in central Grant County. Dry Creek enters Ephrata at the western corporate limits and is then diverted to a ponding area north of the city. Most of the City has been developed. Short, high intensity spring rain showers and snow melt from the Beezley Hills area during quick spring snow melts contributes substantially to the potential flooding. The City has close to 5,000 acres of floodplain and nearly 1,030 individual parcels that are partially or entirely located within the floodplain.

Several floods have occurred on Dry Creek at Ephrata since 1900. The three largest floods occurred in 1901, 1920, and 1948. The 1901 flood was caused by rain combined with snowmelt; the 1920 and 1948 floods were caused by severe thunderstorms. No estimates were made of the peak discharges for the 1901 and 1920 floods. The 1948 flood was reported to be the worst flood in the history of Ephrata, with a peak discharge of 3,080 cfs estimated by slope-area measurements. The estimated recurrence interval is 75 years. This flood was the result of a severe thunderstorm on the evening of May 27. An 8-foot wall of water roared down Dry Creek and broke through the existing diversion dikes at First Avenue Northwest and G Street Northwest, causing extensive damage. A 60-block area of the city was inundated by water and silt. Basements, streets, lawns, and most of the downtown offices at street level were flooded. Storm sewers that were obstructed by silt aggravated the flooding.

Building in the Flood Plain - Reminder: If you plan to construct a new building or improve an existing building located in the flood plain, different standards may apply. The newer standards were adopted to protect property by reducing damage that can be caused by flooding.  Please check with the Building Official Bill Cox (754-4601 ext.135).