foster, a west point trained army engineer, put his skills to good use improving the town's defenses as well as employing the use of three gunboats in the defense. by march 30, the town was ringed with fortifications, and brig. gen. richard b. garnett's brigade began the investment of washington. meanwhile, hill established batteries as well as river obstructions along the tar river to impede reinforcements. he also posted two brigades south of washington to guard for any relief efforts coming overland from new bern. the confederates sent a reply to foster demanding surrender. foster replied saying "if the confederates want washington, come and get it." despite this defiance, foster lacked the strength to dislodge the besiegers, and hill was under orders to avoid an assault at the risk of sustaining heavy casualties. thus, the engagement devolved into one of artillery, and even so the confederates limited their bombings to conserve their ammunition. in time both sides were running low on supplies, and conditions grew miserable in the rain and mud. despite the lack of progress against washington, hill was accomplishing a vital objective in the form of foraging parties so long as the federals were pinned down.